TIGHAR
Amelia Earhart Search Forum => Celestial choir => Topic started by: Gary LaPook on December 07, 2011, 02:39:31 AM
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As far as Lae vs Rabaul: An instrument rated pilot myself, 'trying' to think in terms of a poorly trained (she had vitrually none) instrument pilot, with 1937 navigation technonlogy, and considering where they were, 'personally' I would want as much "dead reconing" as possible during this last leg. Better to calculate wind drift and ground speed early in the flight....before going out over the vast....nothingness! But, that's just me trying to think like a VFR pilot having to go over the ocean....in 1937. I want to fly over as much land as possible.....
And just how many 2,500 mile flights have you made on which the wind correction angle calculated at the beginning worked for the whole flight?
Yep, that's what I thought.
Earhart didn't have to rely on a wind correction angle determined only over land at the beginning of the flight because Noonan had tools that he could use to determine the actual wind encountered in flight and then work out the proper WCA for different portions of the flight. I don't know if your flight instructor taught you how to determine the winds encountered in flight by plotting on your E-6B the heading, the air speed, the ground speed and the track between two landmarks. A navigator can do the same thing between celestial fixes and Noonan himself said "This method proved to have been quite accurate." See page 424 of Weems: https://sites.google.com/site/fredienoonan/resources/weems
Here is an example of how the wind can be determined between fixes by comparing the "no wind position" with the actual fix:
https://sites.google.com/site/fredienoonan/other-flight-navigation-information/in-flight-celestial-navigation
Noonan also had a Mark IIB pelorus with which to take drift readings from which he could determine the wind and the new WCA, see:
https://sites.google.com/site/fredienoonan/topics/measureing-and-determining-wind-speed-and-direction-while-in-flight
and Noonan's description of this process at:
https://sites.google.com/site/fredienoonan/resources/noonan-article/Noonan1936article.pdf?attredirects=0
gl
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That's all fine and good but isn't it a FACT that they didn't find Howland? No matter what Noonan was "capable" of, they didn't find Howland. Something happened along the way.
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That's all fine and good but isn't it a FACT that they didn't find Howland? No matter what Noonan was "capable" of, they didn't find Howland. Something happened along the way.
You noticed that, did you, congratulations.
But they didn't expect that outcome when they took off based on the navigation tools and methods that Noonan used so no reason to do as Mr. Swift suggested.
gl
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Gary,
All I am saying is, I wasn't around in 1937....so I do not know how accurate forecasting winds aloft was....especially in the middle of the Pacific Ocean. A Pilot knows their limitations better than anyone else. I am saying that, if I were in the position AE was in, with available Navigation at the time, I would have wanted to fly over as much land as possible until I headed out over the open ocean. Very seldom winds aloft actually were the same as forcasted when I flew long trips.
Better question might be how many 2,500 mile trips had she flown over an ocean and ended up at the right place?
And great point: Noonan didn't find Howland...did he?
Too bad AE couldn't push the mic button on her yoke and just say "Lae Ground....Electra 16020 IFR Howland Island"...and get her clearance instructions, route, initial altitude assignment, initial frequency, and her transponder code....and take off with clearance from the Lae tower. And then get those vectors to the approach at Howland....and they both live happily ever after. Not so much!
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Gary,
All I am saying is, I wasn't around in 1937....so I do not know how accurate forecasting winds aloft was....especially in the middle of the Pacific Ocean. A Pilot knows their limitations better than anyone else. I am saying that, if I were in the position AE was in, with available Navigation at the time, I would have wanted to fly over as much land as possible until I headed out over the open ocean. Very seldom winds aloft actually were the same as forcasted when I flew long trips.
Better question might be how many 2,500 mile trips had she flown over an ocean and ended up at the right place?
And great point: Noonan didn't find Howland...did he?
Too bad AE couldn't push the mic button on her yoke and just say "Lae Ground....Electra 16020 IFR Howland Island"...and get her clearance instructions, route, initial altitude assignment, initial frequency, and her transponder code....and take off with clearance from the Lae tower. And then get those vectors to the approach at Howland....and they both live happily ever after. Not so much!
Well the winds aloft forecasts in 1937 certainly were no better than today's and today's are not accurate enough to DR to Howland, hence the need for a navigator that had the tools to actually measure the actual winds in flight. Nor would a WCA determined on the first few hundred miles based on pilotage have been accurate enough to find Howland.
gl
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Well the winds aloft forecasts in 1937 certainly were no better than today's and today's are not accurate enough to DR to Howland, hence the need for a navigator that had the tools to actually measure the actual winds in flight.
There is good reason to believe the flight experienced overcast conditions during at least part of the night time portion of the flight. How does a navigator measure actual winds in flight at night while flying over the ocean under an overcast?
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How does a navigator measure actual winds in flight at night while flying over the ocean under an overcast?
By dropping flares?
Chuck
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By dropping flares.
From 10,000 feet???
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By dropping flares.
From 10,000 feet???
Ric,
The closing punctuation to my post should have been a question mark, making it By dropping flares?
Chuck
Yes, by dropping flares from 10,000 feet. The flares only ignite when they hit the water, according to Noonan and he aught to know, see:
https://sites.google.com/site/fredienoonan/resources/noonan-article/Noonan1936article.pdf?attredirects=0
Also see page 34 of U.S. Navy Aircraft Navigation Manual, H.O. 216, available here:
https://sites.google.com/site/fredienoonan/topics/measureing-and-determining-wind-speed-and-direction-while-in-flight
According to H.O. 216 a flare dropped from 8,000 feet hits the water about one mile behind the plane so from 10,000 feet it will hit the water a little farther back. To get the most accurate reading of drift you want to take the observation as far past the flare as possible and the manual mentions 8 nm as a good distance.
So if you think that this can't be done then you are disagreeing with the navigation experts in the U.S. Navy and with Noonan.
gl
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So if you think that this can't be done then you are disagreeing with the navigation experts in the U.S. Navy and with Noonan.
I wouldn't dream of it. So Noonan had flares, was able to use them effectively, got accurate winds aloft information, and was able to navigate accurately to Howland. What are a relief.
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Obviously the next expedition should go to Howland. Come to think of it, it's the only place that wasn't searched! I'd recommend first dividing up the island into a search grid, the looking carefully in each grid section for anything that looks like a large silver airplane.
(sorry, my sense of humor got out of control again)
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As Gary has often pointed out, the Lae/Howland flight was well within the capability of the airplane and navigational methods and technologies of the time and yet the flight failed to reach its intended destination.
Has anyone created some type of guesstimate as to how close they actually came to Howland? The only evidence that I can recall was the radio operator saying that the radio signal strength was excellent, 5 out of 5. Someone had commented that they should have been within 60 miles if this were true although I do not recall where I had read that.
I also read another document that suggested that if there was cloud cover and they were at 1000ft, they might not have been able to differentiate the shadows of the clouds from the island. This seems pretty compelling.
Playing with Google Earth, assuming a 1000ft elevation on a clear day with unlimited visibility, I could see the Howland at about 70-80 miles out. Of course this that is a simulated environment but it might suggest the outer limit of how close they were. On a real aircraft, at 1000ft, assuming perfect conditions, how far out could you be and spot Howland Island? It seems by all accounts they were very close to the destination given the total distance from Lae to Howland.
Are they any opinions as to whether they headed South prematurely or whether they passed to the North and missed Howland when they turned South and passed by it? I am guessing that they headed South prematurely, but this is just a guess.
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Hi Heath. Please take a look at Celestial navigation forum (http://tighar.org/smf/index.php/board,4.0.html). Topic is "Working the flight backwards". In particular reply #95 by Jeff Neville (http://tighar.org/smf/index.php/topic,452.msg5631.html#msg5631). His reply has a clear snapshot of why they turned south when they did. (the theory anyway).
I think in general that the general consensus is they went to far southof Howland, headed north on the LOP but turned back south just a bit too soon.
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As Gary has often pointed out, the Lae/Howland flight was well within the capability of the airplane and navigational methods and technologies of the time and yet the flight failed to reach its intended destination.
Has anyone created some type of guesstimate as to how close they actually came to Howland? The only evidence that I can recall was the radio operator saying that the radio signal strength was excellent, 5 out of 5. Someone had commented that they should have been within 60 miles if this were true although I do not recall where I had read that.
I also read another document that suggested that if there was cloud cover and they were at 1000ft, they might not have been able to differentiate the shadows of the clouds from the island. This seems pretty compelling.
Playing with Google Earth, assuming a 1000ft elevation on a clear day with unlimited visibility, I could see the Howland at about 70-80 miles out. Of course this that is a simulated environment but it might suggest the outer limit of how close they were. On a real aircraft, at 1000ft, assuming perfect conditions, how far out could you be and spot Howland Island? It seems by all accounts they were very close to the destination given the total distance from Lae to Howland.
Are they any opinions as to whether they headed South prematurely or whether they passed to the North and missed Howland when they turned South and passed by it? I am guessing that they headed South prematurely, but this is just a guess.
Looks like Google Earth strikes again. From 1,000 feet the horizon is only 41.6 SM away so anything at sea level beyond that distance is hidden behind the curve of the Earth. If Howland was 20 feet tall then this would add to the distance that you could see the top of that tree by 5.9 SM making a maximum that it might be possible to see Howland 47.5 SM (41.3 NM) no matter how good the meteorological visibility happens to be and it is never that good over the ocean.
See response #67, https://tighar.org/smf/index.php/topic,452.msg5577.html#msg5577
#68, https://tighar.org/smf/index.php/topic,452.msg5578.html#msg5578
and #71, https://tighar.org/smf/index.php/topic,452.msg5583.html#msg5583
on the same thread.
gl
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Hi Heath. Please take a look at Celestial navigation forum (http://tighar.org/smf/index.php/board,4.0.html). Topic is "Working the flight backwards". In particular reply #95 by Jeff Neville (http://tighar.org/smf/index.php/topic,452.msg5631.html#msg5631). His reply has a clear snapshot of why they turned south when they did. (the theory anyway).
I think in general that the general consensus is they went to far southof Howland, headed north on the LOP but turned back south just a bit too soon.
If you read Neville's post #95 then make sure you also read post #87 at http://tighar.org/smf/index.php/topic,452.msg5618.html#msg5618
post # 99, at http://tighar.org/smf/index.php/topic,452.msg5637.html#msg5637
post #104, http://tighar.org/smf/index.php/topic,452.msg5647.html#msg5647
and post #73, https://tighar.org/smf/index.php/topic,452.msg5586.html#msg5586
Then if you want more complete information go to:
https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
and also look at the standard flight navigation texts available here:
https://sites.google.com/site/fredienoonan/topics/landfall-procedure
and more generally here:
https://sites.google.com/site/fredienoonan/
If you read Neville's post #95 then you might also like to ask him about the last time he did a sun line "landfall" approach to an island (I did my last one about seven months ago on May 1, 2011, see: https://sites.google.com/site/fredienoonan/other-flight-navigation-information/recent-landfall-approach and I've done lots of them before) and also ask him when he took his last sextant observation in flight, (I took some today.)
gl
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Rabaul still looks much scarier to me! After just a few minutes in the air.....no more land in site.
A lot of land nearby with a departure from Lae. Still sticking to my opinion on that as a safer departure point. Give me more land to fly by or over until I have to face the loneliness of open water.
I take it you haven't done much flying over the ocean.
Based on her earlier flights, Earhart didn't share your aversion to water. When she flew solo across the Atlantic she departed from Newfoundland and I can tell you there is no land after you "coast out" and go "feet wet" after departing from there. She also flew solo from Hawaii to California, again no land to follow after departure. Then she flew from California to Hawaii on the first attempt, again no land after you put the coast of California behind you. Later, on the second attempt, they flew from Natal to Dakar, guess what, no land after takeoff on that leg either.
So whatever reason she chose to not depart from Rabaul, it was not that she was afraid of having no land in front of her after takeoff.
gl
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Ric sez: "At most destinations Earhart had pre-positioned her own fuel. It's not clear whether that was true at Lae."
Interesting, I wasn't aware of that. Did she have drums of fuel from a reliable source sent to those locations, or pay to have fuel sent to those locations (by the lowest bidder?), or was fuel "pre-paid" at the various airports, trusting it to be of good enough quality?
She had drums of fuel with her name on them pre-positioned at her planned destinations.
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Looks like Google Earth strikes again. From 1,000 feet the horizon is only 41.6 SM away so anything at sea level beyond that distance is hidden behind the curve of the Earth. If Howland was 20 feet tall then this would add to the distance that you could see the top of that tree by 5.9 SM making a maximum that it might be possible to see Howland 47.5 SM (41.3 NM) no matter how good the meteorological visibility happens to be and it is never that good over the ocean.
Gary,
Thank you for the information. I found an online calculate here that takes in to account other factors.
http://mintaka.sdsu.edu/GF/explain/atmos_refr/altitudes.html
Playing with different values of altitude, the island should have been visible at 50 miles. At an altitude of 1500 feet, the observable distance is 60 miles. At 2000ft, 68 miles.
Do we believe that they maintained a constant 1000ft altitude while attempting to find Howland or was there any evidence that she attempted to climb a bit to increase their odds of seeing the island?
Thanks.
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I'm just gonna through this out there and run. As I am not a Pilot or a navigator (just someone interested in flying and this mystery). If it was cloudy and she was at 1000 feet isn't it possible she just flew right over Howland and didn't know it? IF not right over it, close enough were should should see it but didn't?
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There were a number of people on Howland looking and listening for the approaching Lockheed. I think it's safe to say that they would have heard it if it was within 10 miles, and possibly much, much further. She missed seeing it by more than 10 miles, possibly more than a much greater distance, or someone would have heard her engines.
Scattered clouds play hob with a pilot's ability to spot a distant island, from what I've read. They also make a star sight difficult unless you can get above them or in a large open space. The navigator needs to be certain of which star he is seeing, and a minute or two after that to take an elevation.
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Hi Rich. I believe the weather at Howland was clear. If I'm wrong I will be corrected. And Itasca was creating smoke as a beacon.
However, please keep thinking " out of the box" and don't run. While the really knowledgable guys on this forum will occasionally hand out a tongue lashing they can't actually hurt you! LOL.
To Johns point about watchers I would add that even if the watchers had heard her they couldn't communicate with her. No way to say something like "you're passing to the north.". That would have been an even sadder ending if they had heard the plane.
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I believe the weather at Howland was clear. If I'm wrong I will be corrected.
Happy to oblige. See the Itasca Deck Log (http://tighar.org/Projects/Earhart/Archives/Documents/Logs/Itascadecklog.pdf)
Sky conditions that morning during the period in question were 4/10ths to 3/10ths cloud cover.
And Itasca was creating smoke as a beacon.
Maybe, maybe not. Itasca could only make smoke by changing the fuel/air mixture in her boilers and she could only did that for a limited time without really scewing up the boiler tubes. According to the Deck Log (http://tighar.org/Projects/Earhart/Archives/Documents/Logs/Itascadecklog.pdf) she began "laying down heavy smoke" at 0614. By the time Earhart was thought to be close - an hour and a half later - Itasca may no longer have been able to make smoke without causing permanent damage to her propulsion system.
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Thanks Ric. What does "cloud cover" mean? What would the base of the clouds be? Under AE's reported altitude of 1000 feet? Or over?
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Cloud cover means the percentage of the sky that is covered by clouds. 3/10ths cloud cover means that about a third of the sky is covered by clouds.
What the deck log describes is a very typical morning out there - a broken or scattered deck of cumulus with bases at about a thousand feet. As the day warms up the bases gradually rise to maybe 2,500 feet and some of the clouds build into rain squalls.
If Earhart hopes to find land she needs to stay under the bases.
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Ahh. Okay. I thought of cloud cover as that very high solid grey stuff. So she was flying at or, presumably, just under the cloud base for visual searching.
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There were a number of people on Howland looking and listening for the approaching Lockheed. I think it's safe to say that they would have heard it if it was within 10 miles, and possibly much, much further. She missed seeing it by more than 10 miles, possibly more than a much greater distance, or someone would have heard her engines.
Scattered clouds play hob with a pilot's ability to spot a distant island, from what I've read. They also make a star sight difficult unless you can get above them or in a large open space. The navigator needs to be certain of which star he is seeing, and a minute or two after that to take an elevation.
It's pretty easy to be certain that you are looking at the sun and the moon. The moon was also available that morning and its placement in the sky provided a line of position running mainly east-west so would let Noonan know how far north and south they were just like the 157-337 LOP (mainly north-south) let them know how far east or west they were. Because of the moon, and the fact that Itasca reported clear skies to the south, Noonan taking a sight on the moon would have prevented them from flying very far south of Howland and would have kept them from ending up on Gardner.
The Itasca radio log records "partly cloudy" report from Earhart at 1623 Z (look at the 0453 Itasca time entry in Itasca number 2 radio log) so even if Noonan had been prevented earlier from getting star sights by "overcast" conditions you can bet you last dollar that they were going to maneuver the plane in that area to allow Noonan to get a star fix around 1623 Z. They reported "must be on you" at 1912 Z, less than three hours later. At a ground speed of 125 mph the plane covered about 375 SM during that period. The generally accepted estimate of uncertainty of dead reckoning is 10% of distance covered so their position was unlikely to be in error more than 38 SM (and probably much less) at 1912 Z so they would not have been near Gardner.
See standard flight navigation texts available here, (I don't make this stuff up):
https://sites.google.com/site/fredienoonan/topics/accuracy-of-dead-reckoning
https://sites.google.com/site/fredienoonan/topics/accuracy-of-celestial-fixes
https://sites.google.com/site/fredienoonan/topics/landfall-procedure
And an explanation here:
https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
gl
gl
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I believe the weather at Howland was clear. If I'm wrong I will be corrected.
Happy to oblige. See the Itasca Deck Log (http://tighar.org/Projects/Earhart/Archives/Documents/Logs/Itascadecklog.pdf)
Sky conditions that morning during the period in question were 4/10ths to 3/10ths cloud cover.
And Itasca was creating smoke as a beacon.
Maybe, maybe not. Itasca could only make smoke by changing the fuel/air mixture in her boilers and she could only did that for a limited time without really scewing up the boiler tubes. According to the Deck Log (http://tighar.org/Projects/Earhart/Archives/Documents/Logs/Itascadecklog.pdf) she began "laying down heavy smoke" at 0614. By the time Earhart was thought to be close - an hour and a half later - Itasca may no longer have been able to make smoke without causing permanent damage to her propulsion system.
That "scare story" comes from Bob Brandenburg, TIGHAR's radio expert, not a boiler operations expert.
See what I wrote about this before at: https://tighar.org/smf/index.php/topic,383.msg4989.html#msg4989
and: https://tighar.org/smf/index.php/topic,383.msg5025.html#msg5025
I don't claim to be a boiler operations expert (though I do have quite a bit of knowledge about marine steam engines and boilers,) but I can read, and I posted excerpt's from the Navy's standard textbooks on this subject on my prior post. Neither Admiral Knight nor the writers of the Navy Boilerman training text are trying to "advance the theory" of a Gardner landing.
And the other independent witnesses on the scene all reported continuous smoke. So read the references and make up your own mind.
gl
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Thanks Ric. What does "cloud cover" mean? What would the base of the clouds be? Under AE's reported altitude of 1000 feet? Or over?
For those accustomed to reading such things, using what is in the log and doing a few quick computations to find some of the missing values, in present day (or nearly present day) terms, the Hourly weather report would today look something like this
10SCT 9 008/81/77/0703/979
(OK...not really 'Today', I left it in the SA format. I've never liked the new METAR coding, but if someone is more accustomed to the ICAO way of things and wants it I'll convert it.)
The 2/10 to 3/10 cloud cover is today termed to be 'Scattered' (as Ric said). In basic terms it means the sky is 20 to 30 percent covered by clouds. In this case, it indicates that the clouds were cumuliform in nature which means they were lower clouds. There were no actual recorded values for cloud height. In THIS case, however, with the reported temperature and pressure ...and my calculated dewpoint value ... it is predictable that the bases were probably (roughy 85% probability) somewhere in the vicinity of 900 to 1000 ft.
I can say from experience that, with bright sunshine (as it appears there was at the time), the lower the clouds then the darker the shadows they cast on the water surface ...and therefore the more difficult it becomes to differentiate between cloud shadow and land mass.
The visibility was 9 (nautical, presumably) miles / millibar air pressure of 1008mb/ temp 81F (27C) / Dewpoint 77F (25C)/ Winds 070 (ENE) at 03Kts / Air Pressure 29.79 In. Hg
Comparing this observation to the earlier and later observations that day, it does appear to have been a fairly stable weather system. Temps climb and fall as would thus be expected, as well as changes in pressure and and winds throughout the period shown. Although it is interesting to note a 4 degree temperature/dewpoint spread with relatively light winds. This not always, but sometimes, could indicate the possibility of fog and/or haze...there are other factors involved though. The visibility was reported to be 8 to 9 miles throughout the entire period, so it does not appear to have been a factor.
If anything, conditions only got better as the clouds are later recorded as changing from cumulus to higher alto cumulus to cirrus ...which occur at much higher altitudes. Not to mention a steady rise in atmospheric air pressure.
LTM,
....tb
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gl sez: "Noonan taking a sight on the moon would have prevented them from flying very far south of Howland and would have kept them from ending up on Gardner."
Question: could Fred take a sight at extremely high elevation (adding a deadly serious meaning to "shoot the moon")? July 1, 1937, 13:03Z was the moon last quarter, making it near overhead at dawn. I don't recall seeing a navigator's bubble on top of the Lockheed, so the range of sight elevations available may have been quite restricted. I can imagine some extreme frustration onboard the aircraft if there were no good star sights available, yet a moon high in the sky that he couldn't shoot. I'd appreciate any thoughts.
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It's pretty easy to be certain that you are looking at the sun and the moon. The moon was also available that morning and its placement in the sky provided a line of position running mainly east-west so would let Noonan know how far north and south they were just like the 157-337 LOP (mainly north-south) let them know how far east or west they were. Because of the moon, and the fact that Itasca reported clear skies to the south, Noonan taking a sight on the moon would have prevented them from flying very far south of Howland and would have kept them from ending up on Gardner.
That's a pretty good argument that he did not "shoot the moon" because he didn't reach Howland and he apparently did reach Gardner.
The Itasca radio log records "partly cloudy" report from Earhart at 1623 Z (look at the 0453 Itasca time entry in Itasca number 2 radio log) so even if Noonan had been prevented earlier from getting star sights by "overcast" conditions you can bet you last dollar that they were going to maneuver the plane in that area to allow Noonan to get a star fix around 1623 Z.
The Itasca Radio Log has always been interpreted that way but the raw log preserved by Bellarts is not that clear. The log records that at 04:53 Itasca time, the operator sent Earhart the weather on 3105 in both morse code and voice ("fone"). Earhart seems to have "stepped on" that transmission and the operator typed on the same line (HEARD EARHART (PART CLDY). He then went back and typed dashes over the (PART CLDY), hit the carriage return, and continued the dashes through about half of the next line. Why? (The dark line under HEARD EARHART was added much later, probably by Bellarts.)Where the dashes a mistake? Did he change his mind about what he had heard? I don't know but there is certainly room to question whether Earhart said "partly cloudy."
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It's pretty easy to be certain that you are looking at the sun and the moon. The moon was also available that morning and its placement in the sky provided a line of position running mainly east-west so would let Noonan know how far north and south they were just like the 157-337 LOP (mainly north-south) let them know how far east or west they were. Because of the moon, and the fact that Itasca reported clear skies to the south, Noonan taking a sight on the moon would have prevented them from flying very far south of Howland and would have kept them from ending up on Gardner.
That's a pretty good argument that he did not "shoot the moon" because he didn't reach Howland and he apparently did reach Gardner.
The Itasca radio log records "partly cloudy" report from Earhart at 1623 Z (look at the 0453 Itasca time entry in Itasca number 2 radio log) so even if Noonan had been prevented earlier from getting star sights by "overcast" conditions you can bet you last dollar that they were going to maneuver the plane in that area to allow Noonan to get a star fix around 1623 Z.
The Itasca Radio Log has always been interpreted that way but the raw log preserved by Bellarts is not that clear. The log records that at 04:53 Itasca time, the operator sent Earhart the weather on 3105 in both morse code and voice ("fone"). Earhart seems to have "stepped on" that transmission and the operator typed on the same line (HEARD EARHART (PART CLDY). He then went back and typed dashes over the (PART CLDY), hit the carriage return, and continued the dashes through about half of the next line. Why? (The dark line under HEARD EARHART was added much later, probably by Bellarts.)Where the dashes a mistake? Did he change his mind about what he had heard? I don't know but there is certainly room to question whether Earhart said "partly cloudy."
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But radio log 2 was made as a cleaned up copy of the raw log very shortly later. The person typing up log 2 had the opportunity to ask Bellarts at that time, when the facts were the most clear in his head, what Bellarts actually meant by what he had typed in the raw log. Since log 2 does not have dashes over the "part cldy" entry, Bellarts must have clarified this as being what he had heard.
Any other explanation must include that Bellarts was smoking dope at the time and just dreamed up that entry in the raw log.
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It just occurred to me that it may actually have been Bellarts that typed up log 2 so he would have known what he had heard as logged on the raw log when he typed up log 2.
gl
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gl sez: "Noonan taking a sight on the moon would have prevented them from flying very far south of Howland and would have kept them from ending up on Gardner."
Question: could Fred take a sight at extremely high elevation (adding a deadly serious meaning to "shoot the moon")? July 1, 1937, 13:03Z was the moon last quarter, making it near overhead at dawn. I don't recall seeing a navigator's bubble on top of the Lockheed, so the range of sight elevations available may have been quite restricted. I can imagine some extreme frustration onboard the aircraft if there were no good star sights available, yet a moon high in the sky that he couldn't shoot. I'd appreciate any thoughts.
The short answer is "Yes." We know this because Noonan had taken even higher sights using the same octant and shooting through the same windows in the same airplane on the flight to Hawaii and on the leg from Natal to Dakar. I posted a complete explanation of this before at:
https://tighar.org/smf/index.php/topic,383.msg5653.html#msg5653
gl
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Thanks Ric. What does "cloud cover" mean? What would the base of the clouds be? Under AE's reported altitude of 1000 feet? Or over?
For those accustomed to reading such things, using what is in the log and doing a few quick computations to find some of the missing values, in present day (or nearly present day) terms, the Hourly weather report would today look something like this
10SCT 9 008/81/77/0703/979
(OK...not really 'Today', I left it in the SA format. I've never liked the new METAR coding, but if someone is more accustomed to the ICAO way of things and wants it I'll convert it.)
The 2/10 to 3/10 cloud cover is today termed to be 'Scattered' (as Ric said). In basic terms it means the sky is 20 to 30 percent covered by clouds. In this case, it indicates that the clouds were cumuliform in nature which means they were lower clouds. There were no actual recorded values for cloud height. In THIS case, however, with the reported temperature and pressure ...and my calculated dewpoint value ... it is predictable that the bases were probably (roughy 85% probability) somewhere in the vicinity of 900 to 1000 ft.
I can say from experience that, with bright sunshine (as it appears there was at the time), the lower the clouds then the darker the shadows they cast on the water surface ...and therefore the more difficult it becomes to differentiate between cloud shadow and land mass.
The visibility was 9 (nautical, presumably) miles / millibar air pressure of 1008mb/ temp 81F (27C) / Dewpoint 77F (25C)/ Winds 070 (ENE) at 03Kts / Air Pressure 29.79 In. Hg
Comparing this observation to the earlier and later observations that day, it does appear to have been a fairly stable weather system. Temps climb and fall as would thus be expected, as well as changes in pressure and and winds throughout the period shown. Although it is interesting to note a 4 degree temperature/dewpoint spread with relatively light winds. This not always, but sometimes, could indicate the possibility of fog and/or haze...there are other factors involved though. The visibility was reported to be 8 to 9 miles throughout the entire period, so it does not appear to have been a factor.
If anything, conditions only got better as the clouds are later recorded as changing from cumulus to higher alto cumulus to cirrus ...which occur at much higher altitudes. Not to mention a steady rise in atmospheric air pressure.
LTM,
....tb
Here is a photo of what it probably looked like:
https://tighar.org/smf/index.php?action=dlattach;topic=452.0;attach=171
I also posted a photo of land ten miles ahead on this post:
https://tighar.org/smf/index.php/topic,447.msg5573.html#msg5573
gl
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Thanks Ric. What does "cloud cover" mean? What would the base of the clouds be? Under AE's reported altitude of 1000 feet? Or over?
The visibility was 9 (nautical, presumably) miles / millibar air pressure of 1008mb/ temp 81F (27C) / Dewpoint 77F (25C)/ Winds 070 (ENE) at 03Kts / Air Pressure 29.79 In. Hg
LTM,
....tb
According to Itasca's deck log, visibility that whole morning was "9" - the maximum on the scale, defined as "Prominent objects visible above 20 miles."
gl
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There were a number of people on Howland looking and listening for the approaching Lockheed. I think it's safe to say that they would have heard it if it was within 10 miles, and possibly much, much further. She missed seeing it by more than 10 miles, possibly more than a much greater distance, or someone would have heard her engines.
Scattered clouds play hob with a pilot's ability to spot a distant island, from what I've read. They also make a star sight difficult unless you can get above them or in a large open space. The navigator needs to be certain of which star he is seeing, and a minute or two after that to take an elevation.
They were also looking for a ship, see:
https://tighar.org/smf/index.php/topic,383.msg5585.html#msg5585
gl
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" I posted a complete explanation of this before at:
https://tighar.org/smf/index.php/topic,383.msg5653.html#msg5653"
thx gl, excellant link. Sun and moon in good positions for fixes at an appropriate time (good planning?). 'Hard to imagine FN didn't have appropriate tables. 'Got any suggestions where they went wrong from your POV?
We seem to have drifted from "last takeoff footage" a bit ourselves.
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According to Itasca's deck log, visibility that whole morning was "9" - the maximum on the scale, defined as "Prominent objects visible above 20 miles."
Ahh! So it does. I missed the legend on the prior page.
One wonders what 'Prominent Objects' they found over twenty miles away to identify in the middle of the ocean other than Howland itself. Anyone know how far offshore Itasca was parked? Otherwise, all you had to identify was water. Either way, this problem would be the same no matter how you logged the observation.
LTM,
....tb
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Over at the U.S. Coast Guard website, there is a PDF that contains the history of the Itasca. There are a couple pages about Earhart and Howland.
http://www.uscg.mil/history/webcutters/Itasca_1930.pdf (http://www.uscg.mil/history/webcutters/Itasca_1930.pdf)
"The flying conditions within a radius of 40 miles of Howland Island were excellent with an east wind of 8 to 13 miles per hour, the sea smooth and ceiling unlimited as far as could be observed. The sun was rising clear and bright, with the island, the ship and the smoke screen in its glare. Visibility to the north and west was excellent to the horizon, but beyond that continuous banks of heavy cumulus clouds were visible. The plane's transmissions had indicated a flight through cloudy and overcast skies throughout the night and morning, and that dead reckoning distance had been accomplished. The plane's signal strength had been high and unchanged during the last hour of transmission, and its line of position had indicated that the dead reckoning had run correct. Throughout the proceeding night stellar navigating possibilities south and east of Howland and close to Howland had been excellent."
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Isn't this CG PDF contradictory to what the deck log said. See Ric's reply 75 at top of this page. 3/10ths to 4/10ths cloud cover. Should I presume the deck log is likely to be accurate versus an interpreted narrative written later for a history chapter?
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Isn't this CG PDF contradictory to what the deck log said. See Ric's reply 75 at top of this page. 3/10ths to 4/10ths cloud cover. Should I presume the deck log is likely to be accurate versus an interpreted narrative written later for a history chapter?
No, because scattered cloud do not constitute a "ceiling," only "broken" or "overcast" constitute a ceiling. As long as less than 6/10 of the sky is covered by clouds there is no ceiling.
gl
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Rabaul still looks much scarier to me! After just a few minutes in the air.....no more land in site.
A lot of land nearby with a departure from Lae. Still sticking to my opinion on that as a safer departure point. Give me more land to fly by or over until I have to face the loneliness of open water.
BTW sight is spelled s-i-g-h-t.
S-i-t-e means a particular location such as a site for a concert.
Site also means, in the artillery, the difference in the height above sea level between the guns and the target, and this must be allowed for in computing quadrant elevation.
gl
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Looks like Google Earth strikes again. From 1,000 feet the horizon is only 41.6 SM away so anything at sea level beyond that distance is hidden behind the curve of the Earth. If Howland was 20 feet tall then this would add to the distance that you could see the top of that tree by 5.9 SM making a maximum that it might be possible to see Howland 47.5 SM (41.3 NM) no matter how good the meteorological visibility happens to be and it is never that good over the ocean.
Gary,
Thank you for the information. I found an online calculate here that takes in to account other factors.
http://mintaka.sdsu.edu/GF/explain/atmos_refr/altitudes.html
Playing with different values of altitude, the island should have been visible at 50 miles. At an altitude of 1500 feet, the observable distance is 60 miles. At 2000ft, 68 miles.
Do we believe that they maintained a constant 1000ft altitude while attempting to find Howland or was there any evidence that she attempted to climb a bit to increase their odds of seeing the island?
Thanks.
That calculator is much more complicated than is needed for this discussion especially since you do not know the lapse rate. That calculator is appropriate for surveyors with sophisticated instruments. United States Navy Hydrographic Office Publication Number 9, the standard navigation reference text book in the United States, commonly known as "Bowditch," gives the formula as 1.317 times the square root of the height of eye in feet.
gl
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Gary,
All I am saying is, I wasn't around in 1937....so I do not know how accurate forecasting winds aloft was....especially in the middle of the Pacific Ocean. A Pilot knows their limitations better than anyone else. I am saying that, if I were in the position AE was in, with available Navigation at the time, I would have wanted to fly over as much land as possible until I headed out over the open ocean. Very seldom winds aloft actually were the same as forcasted when I flew long trips.
Better question might be how many 2,500 mile trips had she flown over an ocean and ended up at the right place?
And great point: Noonan didn't find Howland...did he?
Too bad AE couldn't push the mic button on her yoke and just say "Lae Ground....Electra 16020 IFR Howland Island"...and get her clearance instructions, route, initial altitude assignment, initial frequency, and her transponder code....and take off with clearance from the Lae tower. And then get those vectors to the approach at Howland....and they both live happily ever after. Not so much!
"Electra November Romeo one six zero two zero" (remember, you must use the "November" when flying internationally) "radar contact lost, resume own navigation, report Itasca outbound." Now what are you going to do?
gl
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The Itasca radio log records "partly cloudy" report from Earhart at 1623 Z (look at the 0453 Itasca time entry in Itasca number 2 radio log) so even if Noonan had been prevented earlier from getting star sights by "overcast" conditions you can bet you last dollar that they were going to maneuver the plane in that area to allow Noonan to get a star fix around 1623 Z.
gl
As an example of the measures that Noonan would have taken to get a celestial fix when the sky was partly cloudy around 1623 Z (0453 Itasca time), I am attaching an excerpt from the book Seaplane Solo by Sir Francis Chichester about the first crossing of the Tasman Sea in 1931. Chichester was flying solo in a Gypsy Moth open cockpit biplane across the 1,450 miles of the Tasman sea in a plane that couldn't carry enough fuel to go that far. He decided to land at the two tiny islands in the Tasman Sea, Norfolk and Lord Howe, but there were no radio stations to help him find those fly-specks. He decided to develop and use the procedure of using a sextant to make a single line of position sun line approach to each of these islands. Chichester is credited with being the person who invented this procedure which was later used by the Air Force, the Navy and by Noonan while flying to Howland. This excerpt shows the desperate measures Chichester had to use to get an observation of the sun through a very small hole in the overcast so he could determine when to make the turn onto the LOP that would take him to Lord Howe. Noonan would have done the same.
gl
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Gary, you wrote:
As an example of the measures that Noonan would have taken to get a celestial fix when the sky was partly cloudy .... Noonan would have done the same.
Gary, why didn't you write:
As an example of the measures that Noonan took to get a celestial fix when the sky was partly cloudy ... Noonan did the same.
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That "scare story" comes from Bob Brandenburg, TIGHAR's radio expert, not a boiler operations expert.
TIGHAR's Bob Brandenburg is LCDR Robert Brandenburg USN (ret), a career naval officer who, among other things, captained a Destroyer Escort during the Vietnam War. I'm sure he'd be happy to compare his knowledge of boiler operations at sea with yours any day.
See what I wrote about this before at: https://tighar.org/smf/index.php/topic,383.msg4989.html#msg4989
In that posting you wrote:
"But this is all a theoretical discussion and we do not have to even consider it since there are all the contemporary eye witness accounts and documents saying that the smoke screen was there for hours, it stretched more than ten miles down wind and would have been visible for 40 miles."
All of the Coast Guard and Navy after-action reports include heavy-doses of not-our-fault, blame-the-victim. Factual errors and false assumptions abound. There was also a noticeable element of getting-our-story-straight. Commander Thompson's (CO of Itasca) "Radio Transcripts Earhart Flight" is the worst of the lot. Many, but by no means all, of the inaccuracies and self-serving distortions in the official reports are described and documented in Finding Amelia.
Elgin Long even includes a photograph of the Itasca making smoke and you can see the quality of the smoke for yourself.
The gentleman's first name is spelled Elgen. He captions the photo in his book:
"The Itasca makes smoke as boats bring ashore a landing party to assist Earhart on her arrival. Note how the smoke lies on the surface and dissipates as it drifts away." The caption is in error. We have the same photo. It came from Itasca's quartermaster Frank Stewart (now deceased). The photo was taken in 1936 during one of Itasca's earlier trips to Howland. The ship is not laying down smoke for Earhart. She's apparently "blowing tubes."
I don't know how long Itasca made smoke but I don't think it matters anyway. I think the available evidence strongly suggests that Earhart was never close enough to see any smoke short of a nuclear test.
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it has been solved just no smokeing gun yet BUT
i think amelia an fred knew exactly were they was, an like amelia's second to last flight were they landed 160 odd miles off course, it attracted more media attention
i think this because in the itasca logs amelia says they are circling but can not see u, circling what!! how would they know they had turned 360 degree's unless hey had a target to judge on which i think was hull an then was able to get to gardner were they were able to land
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which back fired an givin, the fact they were both slim people i.e 8 stone at most, its supriseing they lasted the time to last positive radio call transmission
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That "scare story" comes from Bob Brandenburg, TIGHAR's radio expert, not a boiler operations expert.
TIGHAR's Bob Brandenburg is LCDR Robert Brandenburg USN (ret), a career naval officer who, among other things, captained a Destroyer Escort during the Vietnam War. I'm sure he'd be happy to compare his knowledge of boiler operations at sea with yours any day.
Your authority is Lieutenant Commander Brandenburg, mine is Admiral Knight, I win. ;)
Ask Brandenburg why they couldn't simply blow the boilers at more frequent intervals if there was a concern. And also ask him about the fact that normal procedure had them blowing the boilers at 0800, only 1:46 minutes after the start of the smoke, so no damage yet. (The 1:46 is a maximum time since the deck log states that Earhart called at 0614 and it then logs the start of the smoke but doesn't include a time for starting the smoke. It is unlikely that they started the smoke at the exact same instant as the radio call from Earhart so we can only be sure that the smoke started sometime after 0614. The next log entry is at 0645 and documents another call from Earhart so we can only be sure that the smoke started sometime between these two entries, 0614 and 0645 so it is possible that smoke was only being made for 1:15 prior to the standard blowing of the tubes at the end of the watch at 0800.) So the tubes would be clear at that point (0800) and it was only necessary to make smoke for an additional 43 minutes until Earhart's last report of "157-337 LOP" at 0843. There is no reason to believe that the ship couldn't make smoke for 43 minutes after blowing the boilers.
See what I wrote about this before at: https://tighar.org/smf/index.php/topic,383.msg4989.html#msg4989
In that posting you wrote:
"But this is all a theoretical discussion and we do not have to even consider it since there are all the contemporary eye witness accounts and documents saying that the smoke screen was there for hours, it stretched more than ten miles down wind and would have been visible for 40 miles."
All of the Coast Guard and Navy after-action reports include heavy-doses of not-our-fault, blame-the-victim. Factual errors and false assumptions abound. There was also a noticeable element of getting-our-story-straight. Commander Thompson's (CO of Itasca) "Radio Transcripts Earhart Flight" is the worst of the lot. Many, but by no means all, of the inaccuracies and self-serving distortions in the official reports are described and documented in Finding Amelia.
Except the two wire service reporters had nothing to hide and they could have written block-buster stories disputing the official cover-up of Itasca's failure to provide the smoke that Itasca had promised in a radiogram to Earhart that led directly to her loss. Can we say Pulitzer prize? Also, the Hawaiian radio amateurs on Howland had nothing to hide either, they shared no blame for a lack of a smoke screen and they logged the smoke being made.
I don't know how long Itasca made smoke but I don't think it matters anyway. I think the available evidence strongly suggests that Earhart was never close enough to see any smoke short of a nuclear test.
I agree completely, they never saw the smoke or they would have landed on Howland. That is why I wondered why Brandenburg had to make such a big deal about it.
gl
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Gary. Not seeing the smoke is the only reason they missed Howland????
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In the Itasca log at the Purdue site, just after the 0807 log entry it says in parenthesis, which indicated updates after the actual events, the smoke trail was concentrated and stretched out 10 miles. Granted that who ever wrote this probably created this guesstimate after the events of that day had unfolded. Assuming an 8mph wind, this would suggest that they started the generation of the smoke roughly and hour and a quarter earlier. This of course assume an accuracy of the guesstimate of the trail length and that the time of day this was made was around 0807.
It did not state the elevation of the smoke which would be an important detail for determining how far away they might have been to miss it. Does this boiler smoke rise like another other smoke or would it tend to remain just above sea level?
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That "scare story" comes from Bob Brandenburg, TIGHAR's radio expert, not a boiler operations expert.
TIGHAR's Bob Brandenburg is LCDR Robert Brandenburg USN (ret), a career naval officer who, among other things, captained a Destroyer Escort during the Vietnam War. I'm sure he'd be happy to compare his knowledge of boiler operations at sea with yours any day.
Your authority is Lieutenant Commander Brandenburg, mine is Admiral Knight, I win. ;)
Let's see, how does that go again? Lieutenant Commander; Commander; Captain and then comes Rear Admiral, right?
gl
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N.B. This post has been removed because of ad hominem attacks.I have issued a warning to Gary asking him to confine his remarks to the arguments at hand, and not to impugn the character of other TIGHAR members.
People are free to disagree, but they must adhere to the basic standards of etiquette (http://tighar.org/smf/index.php/topic,377.0.html) for the Forum.
The questions debated here are things about which reasonable people may reasonably disagree. Please act on the assumption that everyone is doing the best that they can to think and speak responsibly.
Marty
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Thanks again Gary,
As I recall from reading somewhere, the Electra was also able to change headings ( ;)), making it theoretically unnecessary for Fred to switch places with Ameila in order to take a sun elevation from the copilot's seat, or from any other window. Distortion through a window is least when shot at angles closest to perpendicular to the glass (plexiglass?), and a heading change for a minute or so would seem well worth the improvement in accuracy. I don't recall seeing any mention of this in Fred's notes or Amelia's writings, so call it hypothetical.
Then again, we also know from her writings that AE used the autopilot, which would also offer Fred ready access to the left hand seat. He obviously had plenty of options to use any window he needed.
Without my doing any research on the subject, I suspect that the 11-degree field of view mentioned was figured assuming a human eyeball in normal seating position, from which point the windshield subtended 11 degrees vertically. It also sloped back quite a bit, offering a much higher view if the human eyeball were to lean forward and look up, or if a sextant or octant were moved to a favorable position nearer to the windshield. 11 degrees is plenty for normal piloting duties.
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That reminds me of a series of exchanges I had with TIGHAR's all around expert, Lieutenant Commander Robert Brandenburg U.S. Navy (Ret.)
I have excerpted below one of our exchanges. This exchange involved various in-flight celestial navigation issues and Lieutenant Commander Robert Brandenburg U.S. Navy (Ret.) was then acting in his navigation expert role (as opposed to his radio expert role or his boiler operations expert role, etc.) He challenged me to explain how Noonan could take various sights. I am including an excerpt of Brandenburg's March 23, 2002 post to illustrate his "expertise" in this area. I have also attached the complete posting and my response as pdf files so you can see the complete context.
I see nothing remarkable in these exchanges. Failure to agree with you does not necessarily constitute a lack of expertise. What I do find remarkable is your contemptuous tone. This is not the first time you've lashed out at someone who doesn't agree with you. Postings like this say a lot more about you than about the person you try to denigrate. I'm asking Marty to put you on the "watch" list.
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Thanks again Gary,
As I recall from reading somewhere, the Electra was also able to change headings ( ;)), making it theoretically unnecessary for Fred to switch places with Ameila in order to take a sun elevation from the copilot's seat, or from any other window. Distortion through a window is least when shot at angles closest to perpendicular to the glass (plexiglass?), and a heading change for a minute or so would seem well worth the improvement in accuracy. I don't recall seeing any mention of this in Fred's notes or Amelia's writings, so call it hypothetical.
Then again, we also know from her writings that AE used the autopilot, which would also offer Fred ready access to the left hand seat. He obviously had plenty of options to use any window he needed.
Without my doing any research on the subject, I suspect that the 11-degree field of view mentioned was figured assuming a human eyeball in normal seating position, from which point the windshield subtended 11 degrees vertically. It also sloped back quite a bit, offering a much higher view if the human eyeball were to lean forward and look up, or if a sextant or octant were moved to a favorable position nearer to the windshield. 11 degrees is plenty for normal piloting duties.
As they were approaching the LOP the sun would have been almost directly in front of them so the place to take those sextant shots was from the co-pilot's seat through the windshield. We know that Noonan did exactly this on the flight to Dakar. At 1237 Z on the way to Dakar, Noonan measured the sun’s altitude with his Bendix bubble octant (a kind of a sextant) through the cockpit windshield as the sun was almost directly in front of them and the measured altitude was 65̊ 34' so he was obviously not constrained by any "11 degree" altitude limit. Also on the way to Dakar, at 1341 Z Noonan took another observation of the sun, this time from the left side cabin
window. He measured 74̊ 48' with his octant. These observations were made using the same octant, through the same windows and in the same airplane as on the Howland flight.
I have attached a list of Noonan's sextant observations on the way to Hawaii and it shows that he was able to take observations in all directions around the plane and as high as 75 degrees.
gl
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Hi Heath. Please take a look at Celestial navigation forum (http://tighar.org/smf/index.php/board,4.0.html). Topic is "Working the flight backwards". In particular reply #95 by Jeff Neville (http://tighar.org/smf/index.php/topic,452.msg5631.html#msg5631). His reply has a clear snapshot of why they turned south when they did. (the theory anyway).
I think in general that the general consensus is they went to far southof Howland, headed north on the LOP but turned back south just a bit too soon.
If you read Neville's post #95 then make sure you also read post #87 at http://tighar.org/smf/index.php/topic,452.msg5618.html#msg5618
post # 99, at http://tighar.org/smf/index.php/topic,452.msg5637.html#msg5637
post #104, http://tighar.org/smf/index.php/topic,452.msg5647.html#msg5647
and post #73, https://tighar.org/smf/index.php/topic,452.msg5586.html#msg5586
Then if you want more complete information go to:
https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
and also look at the standard flight navigation texts available here:
https://sites.google.com/site/fredienoonan/topics/landfall-procedure
and more generally here:
https://sites.google.com/site/fredienoonan/
If you read Neville's post #95 then you might also like to ask him about the last time he did a sun line "landfall" approach to an island (I did my last one about seven months ago on May 1, 2011, see: https://sites.google.com/site/fredienoonan/other-flight-navigation-information/recent-landfall-approach and I've done lots of them before) and also ask him when he took his last sextant observation in flight, (I took some today.)
gl
Gary, I am honored that you continually find me to be such a worthy nemisis to strive to impeach somehow. I MUST be on the right track.
I am happy for your recent experience. Was it done in the Howland vicinity, perhaps? Good for you.
---
So, oh-where-oh-where has my little Lockheed gone? :D
It's a big ocean.
More later.
gl
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Jeff
I, too lean in favor of the Gardiner landing hypothesis.
However, AE's last transmission specified "Running North and South" on LOP 157/337" which is a binary statement. Was she running from 337 to 157 i.e. towards the SSE and Gardiner, or from 157 to 337 i.e. towards NNW and the Marshalls?? Unfortunately she was a sloppy comminicator, and IMHO a sloppy pilot at the very least. Commander Thompson, faced with the ambiguity of AE's binary information, made a choice. He chose to "search" in the NW. OOPS
When the cavalry (the Navy) arrived they spent the better part of a week searching in every direction except the SSE OOPS.
I lean to the SSE because it (the Phoenix Island Group) is closer to where AE was when she realized that she was lost and had better look for some alternate, drier landing place than anything near her then.
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I'm gonna say it and if it is the wrong thing to say, the wrong place to say I am sorry. But why in the world would anyone take off for such a long flight, with such limited window for error. Bound for such a small target with out verifying the radio works both ways. Honestly would any of you pilots do this? If I am to follow all this correct the proof we have (debated or not) is the antenna was ripped off at take off. That means from the get go she could hear no body? Why not turn around? Why not have someway of someone reaching her by chase plane to say we can't hear you? Why go on with no radio? I don't expect an answer as there is no way to get one short of finding a Diary on Niku. Just voicing some frustration with it all. The Logic Ric put's forth with the evedence of the video is sound. It just doesn't make since for someone to continue on with no radio and for everyone there not get word to her via a Chase plane or something. (end rant)
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Re-consider Itasca's initial search effort - her commander acted on what he believed in a very short period of time. The picture had been forming in his head that morning from all that had been pouring in, including probably lots of nuanced opinion all around him. He did the best he could in deliberate haste.
I am really trying to understand the rational of the CG and Navy for their push East and North West. Was there any basis whatsoever for this decision?
Early media reports state that a direction finder was used at some point to say that she was either NW or SE, but I suspect that this information is just not true since the direction finder on Howland had dead batteries and there was no such equipment on the Itasca.
If true, why in the world would they think that she passed North?
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I'm gonna say it and if it is the wrong thing to say, the wrong place to say I am sorry. But why in the world would anyone take off for such a long flight, with such limited window for error. Bound for such a small target with out verifying the radio works both ways. Honestly would any of you pilots do this? If I am to follow all this correct the proof we have (debated or not) is the antenna was ripped off at take off. That means from the get go she could hear no body? Why not turn around? Why not have someway of someone reaching her by chase plane to say we can't hear you? Why go on with no radio? I don't expect an answer as there is no way to get one short of finding a Diary on Niku. Just voicing some frustration with it all. The Logic Ric put's forth with the evedence of the video is sound. It just doesn't make since for someone to continue on with no radio and for everyone there not get word to her via a Chase plane or something. (end rant)
When flying over the ocean I always tracked outbound with my ADF tuned to the departure navaid. This made sure I was heading in the right direction to start with and also proved that the ADF was working. I can't understand why they did not check the operation of their RDF as they flew away from Lae. Her idea that she couldn't get it to work on the test flight was due to being too close to the transmitter shows her lack of knowledge about RDF. As any instrument rated pilot will tell you, the ADF works directly over the station when you are flying an NDB approach.
gl
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Re-consider Itasca's initial search effort - her commander acted on what he believed in a very short period of time. The picture had been forming in his head that morning from all that had been pouring in, including probably lots of nuanced opinion all around him. He did the best he could in deliberate haste.
I am really trying to understand the rational of the CG and Navy for their push East and North West. Was there any basis whatsoever for this decision?
Early media reports state that a direction finder was used at some point to say that she was either NW or SE, but I suspect that this information is just not true since the direction finder on Howland had dead batteries and there was no such equipment on the Itasca.
If true, why in the world would they think that she passed North?
I think the story is just wrong. Itasca based its search on the reported LOP, not on a radio bearing.
gl
its
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Rich
It made no sense for AE to takeoff knowing that her RDF wasn't working during her test flight (She assumed that she was too close to the statioin at Lae).
It made no sense for AE to takeoff without a thorough and complete knowledge of the RDF capabilities at the destination.
Jeff
Here's what I think. FN charted a course from Lae to a point on the LOP 157 to337 that was halfway between Gardiner and Howland (about 202 stature miles SSE of Howland, 202 sm NNW of Gardiner) i.e. an offset to the SSE. That way, when they arrived at the offset point ()600 AM Howland time) they knew to turn NNW and fly the LOP to Howland, arriving there at 0730AM Howland time. The 0614 radio transmission referring to "Am 200 miles out..." was AE reporting her 0600 position on her regularly scheduled 15 minutes after the hour contact. After not spotting Howland at the expected arrival time (0730-0745) "we must be on you but can't see you", she continued on the NNW course 337 for 20 to 30 minutes (44 to 66 miles) and then "circling" back onto the 337 to 157 course heading back to Howland and beyond to the Phoenix Island Group and Gardiner. arriving there about noon Howland time.
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FN charted a course from Lae to a point on the LOP 157 to337 that was halfway between Gardiner and Howland
That almost sounds like the position 1.6S 176W. The reports in the Itasca logs say that direction was not given by the guys in CA and this was also quoted in the media. Somehow later it was supposed to be South West of Howland. Although one of the amateurs had supposedly confessed on tape to a hoax, apparently saying that they made up the report over some Navy conspiracy (sure, sure there was), it is interesting that it is right near the 157/337 heading from Howland, very close to the 1/2 point between Howland and Gardner. Did any of the others ever confess? Could it be that the amateur report had some merit and this guy later fell off his mental rocker? I also read that picking up the 3105 Khz in CA was out of the question / impossible so there is probably no sense in paying it any attention to it.
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ha ha Cynthia it's like Facebook once u pop u can't stop,
the reason i believe an trust Tighar hypothesis, is because they have gone to great length, to gather evidence to back there investigation , were most other research's have based their theory's on second hand info, but Tighar have got there's from actual archive's...
p.s beware ov Ric's alter ego i swear they are a double act ;D
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Rich
It made no sense for AE to takeoff knowing that her RDF wasn't working during her test flight (She assumed that she was too close to the statioin at Lae).
It made no sense for AE to takeoff without a thorough and complete knowledge of the RDF capabilities at the destination.
Jeff
Here's what I think. FN charted a course from Lae to a point on the LOP 157 to337 that was halfway between Gardiner and Howland (about 202 stature miles SSE of Howland, 202 sm NNW of Gardiner) i.e. an offset to the SSE. That way, when they arrived at the offset point ()600 AM Howland time) they knew to turn NNW and fly the LOP to Howland, arriving there at 0730AM Howland time. The 0614 radio transmission referring to "Am 200 miles out..." was AE reporting her 0600 position on her regularly scheduled 15 minutes after the hour contact. After not spotting Howland at the expected arrival time (0730-0745) "we must be on you but can't see you", she continued on the NNW course 337 for 20 to 30 minutes (44 to 66 miles) and then "circling" back onto the 337 to 157 course heading back to Howland and beyond to the Phoenix Island Group and Gardiner. arriving there about noon Howland time.
Harry,
I agree that AE probably believed her RDF capability was full-up when she left Lae, too. What's tragic is what I think Gary pointed out - nearly unbelievable to most of us pilots that she wouldn't have checked it again outbound. Of course our point of view is different in a way - AE was highly focused on 'success' - that of schedule and place (get-there-itis); in fairness, she also had a heavily laden airplane that she would have had to land again (meaning dumping precious fuel) for the sake of that failure. Recall too that she had already chalked-up one apparent non-functioning test to 'being too close to the station' - whether error of understanding or too willing to toss such details aside makes little difference at some point.
Those things don't provide an adequate excuse - I merely see them as reasons that might stack up in AE's thinking that would cause her to toss caution on this detail to the wind and make grander assumptions about success. Think about what we've observed of her habits - that's no big stretch, tragically.
As to the offset navigation -
I don't know - I guess we'll never know for sure. What you say makes sense - but I don't think NR16020 would have had to split the difference between the islands to be 'safe'. Ironically though, she may well have popped up right on the LOP where you are thinking: not realizing how far south she really was (if the case) she may never have quite got into visual range of Baker (south of Howland) before giving up and turning south toward Gardner. It is a plausible outcome and could account for many of the observable pieces in this puzzle. Hence, for me, the soundness of the Gardner landing.
LTM -
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Jeff
The principle of the offset method is to make the offset large enough such that even if you've drifted afar you will still be on the side of the offset and know without question which way to turn when you reach the LOP. If the drift error could be as much as 260 statute miles (10% of the 2560 total miles) then a 202 miles offset would be adequate. The drift error was probably less than that since FN had "fixes" along the course from Lae to the offset point, probably.
Because of my training and background in Accident/Incident(A/I) Investigation I tend to look at this from that point of view when commenting on AE's capabilities and actions. Unfortunately, and yes tragically, all the little errors, oversights, and risks taken all piled up on the Lae to Howland leg and resulted in the tragedy. IMHO there was a lot of pressure to arrive at Oakland on the Fourth of July amid Brass Bands and wildly ecstatic worshippers (I think that George Putnam, the promoter would have seen to that). The delay at Lae also contributed to the "Get home itis". We'll never know.
I think that the "HAR" in TIGHAR stands for Historic Aircraft Recovery and hopefully it's possible to find and recover the Electra. Kinda like the Titanic, except that its location was pretty well known and eventually the technology became available to go and get it.
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The principle of the offset method is to make the offset large enough such that even if you've drifted afar you will still be on the side of the offset and know without question which way to turn when you reach the LOP.
What evidence do you see that an offset was used?
IMHO there was a lot of pressure to arrive at Oakland on the Fourth of July amid Brass Bands and wildly ecstatic worshippers (I think that George Putnam, the promoter would have seen to that). The delay at Lae also contributed to the "Get home itis". We'll never know.
We know this much. Any possibility of getting back to Oakland by July 4 was shot before they left Lae. From Finding Amelia page 75:
Back in California, George Putnam, having learned that his wife had not left Lae on June 30 but not yet aware that the July 1 departure had also been canceled, was still trying to find out whether she would be home in time for the radio engagement Monday night. Knowing that Itasca was trying to establish direct contact with Lae, and hoping to catch Amelia before the scheduled takeoff, he had the Coast Guard’s San Francisco Division send an urgent message to the ship: “Please forward Earhart, Lae. Rush. Is there likelihood Oakland by Monday morning? Reply via Itasca. Important.”27 Itasca never established direct radio contact with Lae, and the message was not forwarded to Lae as a telegram.*
*Over the years there have been accusations that George Putnam pressured his wife to make the flight to Howland before she was ready. While there is no doubt that the messages he sent to her via Itasca conveyed a sense of urgency, Earhart never saw them.
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Ric
I didn't say that GPP was pressurung AE about the Oakland arrival. I said that GPP would have seen to it that there was a crowd of enthusiastic people there to greet her on the Holiday. So AE didn't get a message or a telegram, so what? Does that mean that she didn't feel a certain amount of anxiety over the delays and perhaps increase her "Get home itis"?
As for the Offset., I was proposing a sub-hypothesis. FN was very knowledgable in the use of an offset. AE's 0614 transmission could have been announcing her arrival at the offset point ("200 miles out"). Probably arrived there at 0600 but didn't announce it until her regular 0615 time for transmissions. "Running N and S on the LOP 157/337..." Yep, NNW from the offset point towards Howland then "circling" back SSE on the LOP.
What is your evidence that they travelled a straight line (rhumb line or sreat circle) route to Howland?
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Jeff
The principle of the offset method is to make the offset large enough such that even if you've drifted afar you will still be on the side of the offset and know without question which way to turn when you reach the LOP. If the drift error could be as much as 260 statute miles (10% of the 2560 total miles) then a 202 miles offset would be adequate. The drift error was probably less than that since FN had "fixes" along the course from Lae to the offset point, probably.
Harry,
I'm trying to follow you reasoning about you theory of a 202 mile offset to the south-southeast.
1. Do you believe that they deliberately planned to intercept the 157-337 LOP 202 SM out to the south-southeast?
2. What do you believe was Noonan's estimate of maximum possible error in his dead reckoning at the point that they intercepted the LOP?
gl
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Gary
1.Yes
2.I don't know cause I don't know when/where he had the last "fix" (I mean his celestial "fix"), but in any case less than 200 miles.
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"Running N and S on the LOP 157/337..." Yep, NNW from the offset point towards Howland then "circling" back SSE on the LOP
Who are you quoting? Certainly not AE. She never said anything about an LOP and she almost certainly never said she was "circling." See Things Not Said (http://tighar.org/Publications/TTracks/1995Vol_11/said.pdf)
What is your evidence that they travelled a straight line (rhumb line or sreat circle) route to Howland?
Primarily the utter absence of evidence that they did anything else. If AE was an accomplished aerobatic pilot would you propose that she flew the last few hundred miles inverted? Fred didn't use an offset when flying the Pan am Pacific routes. He didn't use an offset on the Earhart flight from Oakland to Honolulu. He didn't intentionally use an offset on the South Atlantic crossing.
On the other hand, maybe she did fly the approach to Howland inverted. How would we ever know?
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Gary
1.Yes
2.I don't know cause I don't know when/where he had the last "fix" (I mean his celestial "fix"), but in any case less than 200 miles.
3. How far did they fly on a course of 337° true to ensure that they would find Holwand after intercepting the LOP to the south-southwest?
gl
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Gary
3. 202 miles to the vicinty of Howland then 44 to 66miles (20-30 minutes at 134 nph) WNW of where they expected to see Howland, then they circled back towards Howland and continued on to Gardiner.
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Ric
I see, no evidence found for A, nor B, therefore it must have been C, even though there is no evidence for C (straight line route).
Your "nverted " annology is beneath you and doesn't deserve serious consideration nor comment.
I'll have to look at the Itasca radio log info to source the info for you.
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Ric
I see, no evidence found for A, nor B, therefore it must have been C, even though there is no evidence for C (straight line route).
Your "nverted " annology is beneath you and doesn't deserve serious consideration nor comment.
I'll have to look at the Itasca radio log info to source the info for you.
Absence of "A" and "B" may provide evidence of "C", given a couple of things:
- FN had before expressed use of celestial and radio beam in what sounds alot like direct routing for Pan Am
- FN appears to have been expecting a similar approach by the presence of NR16020's RDF equipment, etc.
We'll never know for sure in this world - the truth of it evaporated from the grey matter in a couple of skulls somewhere in the Pacific long ago, and NR16020 can never reveal that secret (short of a message in a bottle).
All would not be 'lost', however, if a direct route attempt failed at first: the off-set principle could have still been applied after the fact of realizing your original plan failed. Consider: if the Gardner theory is correct, then it was not a failure of FN's navigation so much as a failure to be detected on Gardner, for whatever set of reasons.
As to 'inverted', well, don't be too hard on Ric - AE did seem to spend a lot of time standing on her head. :P
LTM -
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Ric
PDF of Itasca radio log
Position2 page 3 WL Galten time around 0843
"KHAQQ to ITASCA
We are on the line 157 337 ... We are running on line... "
I wonder what line she is referring to Maybe the line of position LOP 157/337? Ya Think?
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I wonder what line she is referring to Maybe the line of position LOP 157/337? Ya Think?
Yes I do, as does just about everybody, but you quoted AE as saying "Running N and S on the LOP 157/337..." and it's dangerous misquote sources. Even though we all agree that she was referring to an LOP we must keep in mind that it's an assumption.
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Ric
My apologies for committing the "dangerous" act of adding the obvious to the radio message.
337 is 23 degrees W of North and 157 is 23 degrees E of South. She was running N and S on the line (actually she was probably running NNW and SSE on the line but we have to allow for her sloppiness as a radio communicator). How else could she be running? East and West on the line 157 337?
I've read your opinions with respect to the 0843 message and they are just that, opinions, assumptions.
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I've read your opinions with respect to the 0843 message and they are just that, opinions, assumptions.
The documented references to the last message being heard at 08:55 are neither opinions nor assumptions.
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Ric
I wasn't aware that I was commenting in any way, except for referring to the time in Galten's log, about the time. The man putting the info in his log wrote the time as 0843 (first evidence, best evidence).
In your Project Research Bulletin "Last Words" dated 04/07/2007 there are numerous quotes to a transmission "We are running N and S on the line 157.337" If she didn't say it, why do yoiu refer to it and attribute it to Thompson, Carey, et al in that research bulletin?
Your interpretations of XX overs, paten moves, etc time changes, etc are just that interpretations, opinions.
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In your Project Research Bulletin "Last Words" dated 04/07/2007 there are numerous quotes to a transmission "We are running N and S on the line 157.337" If she didn't say it, why do yoiu refer to it and attribute it to Thompson, Carey, et al in that research bulletin?
You apparently don't understand what I wrote. I quoted Galten, Thompson and Carey accurately.
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I do understand what you wrote. Apparenty at least three individuals (Galten, Thompson and Carey), who were present at the time of the transmission, thought that they had heard her say "we are running North and South on the line 157 337" The line 157/337 was also referred to as the LOP. That's good enough for me, AE said it.
Whether she said it at 0843 Galten's time or 0855 Thompson and Carey's time or 0825 Gillespie's time is not the topic of my post about AE having said it. She said it!
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Gary
3. 202 miles to the vicinty of Howland then 44 to 66miles (20-30 minutes at 134 nph) WNW of where they expected to see Howland, then they circled back towards Howland and continued on to Gardiner.
4. You said that they intercepted the LOP at 0600, is that Itasca time, the same as 1730 Z?
gl
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Gary
No, 1800 GCT (0600 Howland time).
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Gary
No, 1800 GCT (0600 Howland time).
There is some ambiguity about the time scales. Based on standard time zones, the time on Howland would have a zone description of + 12 so that 0600 would be 1800 Z
But the time actually being kept on Howland by the colonists was the same as Hawaiian time with a zone description of +10:30 making your 0600 the same as 1630 Z.
The time kept on the Itasca had zone description of +11:30 making your 0600 the same aw 1730 Z. (Ric has used this as "Howland time.")
If you are comparing your times to those in the Itasca logs then you are apparently using Itasca time. Since you are talking about her radio messages logged on the Itasca it appears that you are actually using Itasca time. So your 0600 is actually 1730 Z.
See:
https://tighar.org/smf/index.php/topic,433.msg5362.html#msg5362
gl
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No, 1800 GCT (0600 Howland time).
I believe that in 1937, Itasca time was offset from GMT by 11.5 hours.
GMT - 11.5 = Itasca time.
See Randy Jacobson's explanation of the 1937 time zones (http://tighar.org/Projects/Earhart/Archives/Research/JacobsonDatabase/RADIOMES/TIMEZONE.PDF), which is essential for understanding The Jacobson Databases (http://tighar.org/Projects/Earhart/Archives/Research/JacobsonDatabase/JacobsonDB.html), which, in turn, underlie much of TIGHAR's research into the fatal flight and post-loss radio messages (http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/signalcatalog.html).
I've tried to copy Jacobson's table into a new article in the Ameliapedia (http://tighar.org/wiki/Timezones). I've also done my level best to calculate the Itasca time for the transmission timeline (http://tighar.org/wiki/Transmission_timeline).
- I can't explain why Jacobson used a convention that is the opposite of the current UTC convention. Perhaps that reflects how time zones were calculated in the GMT/Zulu days.
- I don't trust my math.
Corrections and comments most welcome.
Another maddening wrinkle: the Howland log was kept on GMZ-10.5 while the Itasca was on GMZ-11.5 (http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Worldflight/finalflight4.html).
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Gary
My 0600 time (1800 GCT) was based on an estimate of 2400 sm from Lae to the midpoint of the distance between Howland and Gardiner on the 157/337 line at an estimated "ground" speed of 133.33 mph (400 miles in 3 hours), i.e. 18 hours for the trip to that point.
I'm not sure what time that would have been in the radio room, o530 I suppose.
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Which time zone was requested by Earhart? I forget but I recall it was different from Itasca.
If the Itasca log was 30 minutes different from all the other time zones, if Earhart sent out a message at 15 minutes after the hour, this was marked as 45 minutes after the hour in the Itasca log?
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Which time zone was requested by Earhart? I forget but I recall it was different from Itasca.
GMT, a.k.a. Zulu, a.k.a. UTC.
If the Itasca log was 30 minutes different from all the other time zones, if Earhart sent out a message at 15 minutes after the hour, this was marked as 45 minutes after the hour in the Itasca log?
Yes.
You can see how it works out (if my math is correct) in the transmission timeline (http://tighar.org/wiki/Transmissions_heard_from_NR16020). The GMT times are from Randy Jacobson's work. I've done the math myself for the Itasca time. I dug out my old Hex and Time calculator (Radio Shack EC-4075) from the mid-80s and checked my work after first doing it by hand.
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Gary
3. 202 miles to the vicinty of Howland then 44 to 66miles (20-30 minutes at 134 nph) WNW of where they expected to see Howland, then they circled back towards Howland and continued on to Gardiner.
5. Why do you have them flying an additional 44 to 66 miles if you think they were only 202 miles south-southeast of Howland when they intercepted the LOP? Why don't they turn around after just flying the 202 miles to Howland? Doesn't this just waste time and fuel?
gl
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No, 1800 GCT (0600 Howland time).
I believe that in 1937, Itasca time was offset from GMT by 11.5 hours.
GMT - 11.5 = Itasca time.
See Randy Jacobson's explanation of the 1937 time zones (http://tighar.org/Projects/Earhart/Archives/Research/JacobsonDatabase/RADIOMES/TIMEZONE.PDF), which is essential for understanding The Jacobson Databases (http://tighar.org/Projects/Earhart/Archives/Research/JacobsonDatabase/JacobsonDB.html), which, in turn, underlie much of TIGHAR's research into the fatal flight and post-loss radio messages (http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/signalcatalog.html).
I've tried to copy Jacobson's table into a new article in the Ameliapedia (http://tighar.org/wiki/Timezones). I've also done my level best to calculate the Itasca time for the transmission timeline (http://tighar.org/wiki/Transmission_timeline).
- I can't explain why Jacobson used a convention that is the opposite of the current UTC convention. Perhaps that reflects how time zones were calculated in the GMT/Zulu days.
- I don't trust my math.
Corrections and comments most welcome.
Another maddening wrinkle: the Howland log was kept on GMZ-10.5 while the Itasca was on GMZ-11.5 (http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Worldflight/finalflight4.html).
I take it you are confused by the sign convention. For navigation purposes it is important to be able to determine Zulu time which is the entering argument for the Nautical Almanac. The navigation and navy sign convention makes this easy. You start with the local time shown on the ship's clocks and then apply the Zone Description which then gives you Zulu (GMT) time. For instance, the navigator on the Itasca takes an observation of the sun at 0815 ship's time. He then applies the Zone Description of + 11:30 and determines the GMT of the observation as 1945 Z which is the value he needs to enter his Nautical Almanac. The ships are not concerned with determining the time at other locations other than at Greenwich.
Other users are interested in converting GMT to local time so they use a reversed sign for the conversion factor. Using the same values as above, 1945 Z minus 11:30 makes the time on Itasca 0815.
See my prior post:
https://tighar.org/smf/index.php/topic,433.msg5362.html#msg5362
gl
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Jeff, et al;
GL has his own web pages presenting his ideas about the flight:
https://sites.google.com/site/fredienoonan/home
Those are good pages to visit to identify what points are weell supported, and what points are open to interpretation, and what points are based on assumptions.
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Hi John
To save us all some time can you point us to the part of Gary's website that says what he believes happened? I see lots of sections on why TIGHAR is wrong but nothing leaps out on Gary's hypothesis.
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Here's the closest I've found to Gary stating what he believe happened:
"It is most likely that they had planned to use the radio as the primary, or preferred, method for finding Howland since it is easier to use and saves you the time and distance necessary for the landfall procedure. However, the celestial landfall procedure is accurate enough, by itself, to find Howland so was perfectly adequate as a backup, or secondary, method for completing the flight. When they failed to get the radio signals at the point that they had that expected to be able to receive them, they would have turned to commence the landfall procedure with the knowledge that if they did start receiving the radio signals they could abandon the landfall at that point and turn and follow the radio bearings directly to the island. There is no other explanation for their report of being on the 157-337 line except that they were flying the landfall since that line has absolutely no relevance to any other approach."
(from https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island)
I take Gary's statement to mean that he believes the flight most likely continued to try to navigate towards Howland until they ran out of fuel. He's obviously spent a lot of time and effort considering the various evidence and hypotheses', so he makes a very good foil to sharpen any other hypothesis. I'm glad he participates here, regardless of how irritating he may be at times, and I encourage TIGHAR folks to visit his pages for a different and thoughtful perspective.
Note that I don't think he is "right", any more than I think TIGHAR is "right". That is a decision to be made if and when the Electra is found.
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Hi John. Thanks for that info. It helps and your encouragement to others to go and visit Gary's site is appropriate. I have been to his site myself on several occasions but always come away feeling that the site is setup to say why TIGHAR is wrong in its thinking. Not "but here's what I, Gary Lapook, think".
Your entry above has your interpretation of what you believe Gary thinks. It doesn't point to the Lapook hypothesis. What we would like to hear from Gary is his hypothesis or theory and not a rehash of why TIGHAR is wrong. In a court a prosecutor has to prove what happened using evidence. To different degrees of certainty depending on the court. A defense lawyer needs to only show that the prosecutor is wrong to win his case. I feel that's what Gary tries to do. What I would like to see is Gary to take off his lawyer's hat and just render his personal opinion on what happened. No judge, no jury, no court decision. Just one of a bunch of guys sitting around a kitchen table sharing his thoughts over a beer. No condemnation, no insults, no judgement. Gary's current method of trying to convince us TIGHAR is wrong is dead ending because he isn't putting an alternative forward. Ric has passion and conviction in his hypothesis. Gary seems to have that same passion and conviction for disproving Ric. What drives that passion? Gary??
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I am still trying to understand why Eahart and Noonan selected the 157/337 "line" which I believe everyone assumes to be the Advanced Line of Position described here:
http://tighar.org/Projects/Earhart/Archives/Forum/FAQs/navigation.html (http://tighar.org/Projects/Earhart/Archives/Forum/FAQs/navigation.html)
If they did establish their own LOP at sunrise, and there seems to be considerable debate whether that was even possible, why follow the ALOP at all? Was it because they were on a 247/67 heading that is 90 degrees from the 157/337 LOP at Howland and they made that heading change when they set their own LOP at sunrise?
Reliance on being able to see the sunrise in advance, with unknown weather conditions ahead, at pre-dawn, would seem to be very risky. Perhaps it was a backup plane in case Fred could not establish celestial navigation? There must have been some pre-planning going on there to intercept this ALOP from the start, regardless of the celestial navigation, and ability to establish a LOP. If both failed, would they have been forced to falling back to estimates based on the compass heading and timepiece as the last resort? Given that they had no ability to measure the head winds (short of dropping flares) do we believe it had been that been for them?
I like the idea of an offset as this seems to be the most logical thing to do (even for a layperson like myself), ensuring that you hit hand if you somehow drifted North. Do not go directly for the target but hit this line a bit South to ensure success of hitting something sooner or later. I cannot see a reasonable argument that suggests that they did not do this to some degree.
Maybe it was not the midpoint between Howland and Gardner, but it was somewhere on that line based on Fred's confidence level.
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Gary
5. They flew the 200 or so miles on the LOP towards where they expected Howland to be, didn't spot it, radioed in "we must be on you...", continued on the LOP for 20 to 30 minutes and still didn't spot it so they decided to return along the 337 to 157 course and after they travelled 20 to 30 minutes back to where they had expected Howland to be and still not spotting it radioed "running N and S on the line 157/337" and continued on to the Phoenix Island group (Gardiner?)
We must bare in mind that there is a chance that FN's chart had Howland mislocated by 5 nm to the west of its "true" position. Why did they miss Howland? We'll probably never know.
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Reliance on being able to see the sunrise in advance, with unknown weather conditions ahead, at pre-dawn, would seem to be very risky. Perhaps it was a backup plane in case Fred could not establish celestial navigation?
Observing the time of sunrise from a particular alititude is celestial navigation. The sun is just one of the heavenly bodies that can be used to generate a line of position (http://tighar.org/wiki/Line_of_position).
There must have been some pre-planning going on there to intercept this ALOP from the start,
Not necessarily. It was one tool in Fred's arsenal, I believe.
I like the idea of an offset as this seems to be the most logical thing to do (even for a layperson like myself), ensuring that you hit hand if you somehow drifted North. Do not go directly for the target but hit this line a bit South to ensure success of hitting something sooner or later. I cannot see a reasonable argument that suggests that they did not do this to some degree.
This is a moot point (http://tighar.org/wiki/Moot). It is something about which reasonable people can reasonably disagree and which makes absolutely no difference to deciding where to look for the pieces of the Electra. Arguments about what our heroes coulda, shoulda, woulda done are incapable of resolution--unless, of course, someone finds Fred's charts from the fatal flight.
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unless, of course, someone finds Fred's charts from the fatal flight.
Or models like the doughnut hole theory (or other radio models) could give credence to the idea.
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I am still trying to understand why Eahart and Noonan selected the 157/337 "line" which I believe everyone assumes to be the Advanced Line of Position described here:
http://tighar.org/Projects/Earhart/Archives/Forum/FAQs/navigation.html (http://tighar.org/Projects/Earhart/Archives/Forum/FAQs/navigation.html)
If they did establish their own LOP at sunrise, and there seems to be considerable debate whether that was even possible, why follow the ALOP at all? Was it because they were on a 247/67 heading that is 90 degrees from the 157/337 LOP at Howland and they made that heading change when they set their own LOP at sunrise?
Reliance on being able to see the sunrise in advance, with unknown weather conditions ahead, at pre-dawn, would seem to be very risky. Perhaps it was a backup plane in case Fred could not establish celestial navigation? There must have been some pre-planning going on there to intercept this ALOP from the start, regardless of the celestial navigation, and ability to establish a LOP. If both failed, would they have been forced to falling back to estimates based on the compass heading and timepiece as the last resort? Given that they had no ability to measure the head winds (short of dropping flares) do we believe it had been that been for them?
I like the idea of an offset as this seems to be the most logical thing to do (even for a layperson like myself), ensuring that you hit hand if you somehow drifted North. Do not go directly for the target but hit this line a bit South to ensure success of hitting something sooner or later. I cannot see a reasonable argument that suggests that they did not do this to some degree.
Maybe it was not the midpoint between Howland and Gardner, but it was somewhere on that line based on Fred's confidence level.
You'll find the answers to all of your questions here:
https://sites.google.com/site/fredienoonan/discussions/the-myth-of-the-sunrise-lop
https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
https://sites.google.com/site/fredienoonan/other-flight-navigation-information/recent-landfall-approach
https://sites.google.com/site/fredienoonan/topics/landfall-procedure
gl
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Gary
5. They flew the 200 or so miles on the LOP towards where they expected Howland to be, didn't spot it, radioed in "we must be on you...", continued on the LOP for 20 to 30 minutes and still didn't spot it so they decided to return along the 337 to 157 course and after they travelled 20 to 30 minutes back to where they had expected Howland to be and still not spotting it radioed "running N and S on the line 157/337" and continued on to the Phoenix Island group (Gardiner?)
But what you are saying doesn't make any sense, You had then aim for a spot 200 miles south-southeast on the LOP on the assumption that the uncertainty, or possible error, in the DR approaches 200 miles. But, they could be off course either to the right or to the left of the the 200 mile offset position along the LOP that you aimed for, so they might actually have intercepted the LOP 200 miles further out to the south-southeast, a total of 400 miles from Howland. You then have them turning left and flying 200 miles along the LOP to the spot where they expect Howland to be. You then have them flying only 44 to 66 miles further prior to turning around but they actually must fly an additional 200 miles to ensure that they have flown far enough to find Howland because of the possiblity that they actually intercepted 400 miles from Howland.
See: https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
gl
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Well said Jeff. I second the motion. Gary??
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Gary,
I was looking over your links and found this one:
https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxmcmVkaWVub29uYW58Z3g6M2I5OTVhMWZmMmI4ZDFiZA&pli=1
---
Landfalls - The safest way to get to destination
Landfalls are of two types: course line landfalls and speed line landfalls.
Course Line Landfall
The easiest landfall to fly and things being equal, the most accurate. is the course line landfall.
1. Observe a celestial body that gives a course line, line of position. Plot it on your Mercator chart
2. Advance the line of position through destination parallel to the one you just plotted.
3. Fly directly to the line of position through destination and turn toward destination.
4. Stay on this line of position until another line of position shows you to be off course.
5. Then repeat the process. But stay on a line of position through destinatiun. There is no ETA in a landfall other than your best known ground speed.
Speed Line Landfall
Because a course line is at times the more difficult type of line of position to observe, and because sometimes only speed lines are available, you will also fly a speed line landíall.
In this type of landfall fly definitely to one side of destination. When you reach the speed line through destination, turn and fly into destination.
---
It seems to me (with zero expertise in this area) that Course Line Landfall requires being able to measure some celestial body (Sun or stars). This would also imply (to me) that in order for Earhart to end up on the 337/157, they must have had a approach heading 90 degrees from the advanced line of position (Howland) and that they would have definitely had some celestial reference to use. Again, to me, this seems like a risky strategy in pre-dawn conditions, perhaps overcast, where you cannot be certain that you will find any reference. This approach only works assuming you have some reference correct?
The Speed Line Landfall on the other hand requires that you chose a point that is "definitely to one side of destination". This might be used when you may perhaps have only ground speed data that you have recorded since your last verified position correct?
So given the above advice, are we not just debating over the the degree of being "definitely to one side of destination" if a Speed Line Landfall was used?
Thanks in advance.
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i don't think Gary has any issue with the Gardner hyposis, he is just trying to explain why he thinks Tighar theory ov the lop is wrong,
u only have to look at his website an see its mostly about the lop nothink else
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But, what do you think happened, Gary?
Again you have offered up another critique - fine, it's an open forum. And you've offered more references to your website, which is very interesting - thanks for that, I find much of interest there and it is very generous of you.
But I (and perhaps others) STILL don't get a real sense of WHAT you think happened (cohesive hypothesis).
It occurs to me that we TIGHAR forum participants may fall roughly into three essential categories:
1 - Those who for whatever reasons believe in the TIGHAR-Niku hypothesis
2 - Those who are interested and are exploring - some with little or no comment, others who venture in
3 - Those who are committed to a belief in an outcome that is other that the TIGHAR-Niku hypothesis
Nothing wrong with any of that, and Ric and Marty, among others, have repeatedly assured us of an open forum. That is productive - and takes courage of conviction, by the way.
It also means challenges are viewed as healthy - and I agree with that. But vigorous challenges that so consistently seek to refute someone else's point ought to be backed by an equally firm conviction of a different belief. Do you really search for NR16020, or do you simply believe that TIGHAR's hypothesis must be dismantled for some reason? I don't have any real fear of that. It's too solid for too many reasons, and there can be no meaningful search without some form of a compass on where to look and what to look for - and too many of us are devoted to learning the full story one day.
So I would be a fool to not respect other opinions - but I find those opinions most useful when there is real conviction behind them. Then where would you have us search, Gary? To keep ruminating over your points gives little, if any, direction. Lots of great information on your site, by the way - most enjoyable and what you offer is very generous. But if you'd spend so much time and effort trying to impeach the Niku hypothesis, what is it that you believe so passionately that could lead someone to think in an equally productive direction if they want to find NR16020 and what happened to AE and FN?
So, I for one would like to know what you really think if you can share it. I promise to respect it, as I think others here would as well. Granted, with many of us you would have a lot to overcome - lots of facts, reasonable observations and painstaking field work of many years by some very respectable people. But your opinions are respected and appreciated.
Maybe it's partly a 'tone' issue, but maybe it's also about substance: time and again ideas are posted here only to have you tear at them as if a barrister fighting to keep a prince from an appointment with the gallows. A time or two I've even caught myself wondering "who (WHAT) IS Gary defending, that it's so important to 'defeat' TIGHAR's and other's ideas so often?" That's kind of silly - or is it? 'Tone' may suggest many things to a perspiring mind. :D But you have said to me in a recent response: "it's a big ocean" and implied 'stay tuned' - so I am piqued - maybe you are trying to put a hypothesis together. Maybe others would agree with me that it would be good to see what convictions lie behind your theme of 'discussion' here. Then we can respectfully critique your own ideas too.
By this thread we've reviewed the take-off and ventured into much that went afterward, and why. We can probably agree that the take-off and eastward progress toward Howland did happen. So how about the rest of the flight and outcome? When can we see what you really have in mind? Do you think there is a significant-other theory, or do you think trying to rationally derive a working theory to eventually find NR16020 and realize AE's and FN's fate is just non-sense?
Probably time for a new thread, folks...
LTM -
I'm working up to it, so I will post it soon. I'm not being coy, I just have some preliminary stuff to put together.
gl
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Gary,
I was looking over your links and found this one:
https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxmcmVkaWVub29uYW58Z3g6M2I5OTVhMWZmMmI4ZDFiZA&pli=1 (https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxmcmVkaWVub29uYW58Z3g6M2I5OTVhMWZmMmI4ZDFiZA&pli=1)
---
Landfalls - The safest way to get to destination
Landfalls are of two types: course line landfalls and speed line landfalls.
Course Line Landfall
The easiest landfall to fly and things being equal, the most accurate. is the course line landfall.
1. Observe a celestial body that gives a course line, line of position. Plot it on your Mercator chart
2. Advance the line of position through destination parallel to the one you just plotted.
3. Fly directly to the line of position through destination and turn toward destination.
4. Stay on this line of position until another line of position shows you to be off course.
5. Then repeat the process. But stay on a line of position through destinatiun. There is no ETA in a landfall other than your best known ground speed.
Speed Line Landfall
Because a course line is at times the more difficult type of line of position to observe, and because sometimes only speed lines are available, you will also fly a speed line landíall.
In this type of landfall fly definitely to one side of destination. When you reach the speed line through destination, turn and fly into destination.
---
It seems to me (with zero expertise in this area) that Course Line Landfall requires being able to measure some celestial body (Sun or stars). This would also imply (to me) that in order for Earhart to end up on the 337/157, they must have had a approach heading 90 degrees from the advanced line of position (Howland) and that they would have definitely had some celestial reference to use. Again, to me, this seems like a risky strategy in pre-dawn conditions, perhaps overcast, where you cannot be certain that you will find any reference. This approach only works assuming you have some reference correct?
The Speed Line Landfall on the other hand requires that you chose a point that is "definitely to one side of destination". This might be used when you may perhaps have only ground speed data that you have recorded since your last verified position correct?
So given the above advice, are we not just debating over the the degree of being "definitely to one side of destination" if a Speed Line Landfall was used?
Thanks in advance.
Good, I'm glad that you took the time to read that excerpt from the 1944 Navigator's Information File. You should also read the other references I posted such as Force Manual 51-40 (1951 and 1973) and Weems (1938) and other reference books available here (https://sites.google.com/site/fredienoonan/topics/landfall-procedure). You can also read my analysis here (https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island). From your question I think a little more explanation might be helpful since that excerpt didn't cover some more basic stuff about celestial navigation.
A "course line" LOP is one that runs parallel to your course line (or nearly so) so when you plot it on your chart and compare it with the desired course line you can ascertain if you are on course or off to the left or to the right. Since LOPs plot at right angles to the azimuth to the celestial body, a course line LOP involves observing an object out on the wingtip (or nearly so) and after you do the computations the resulting LOP is parallel to your course line (or nearly so.)
A "speed line" LOP is one that plots across your course line at a ninety degree angle (or nearly so) and shows how much progress you have made towards your destination and this allows you to calculate your ground speed and estimate the time you should arrive at your destination. Or. more accurately, the time you will have flown far enough to reach your destination since a "speed line" gives you no information as to whether you are on the correct course to actually hit your destination, you may arrive at the correct distance but be far off to the side.
Since being on course is the most important part about finding the destination, and the exact time of arrival is less important, you must find a way to get on a "course line" that runs through the destination. If there is only one celestial object available for observation you must arrange it so that your final approach is on a course that puts the object out on the wingtip and so the resulting LOP is a "course line." This is the entire purpose of turning off to one side to then intercept an LOP that is a "course line" through the destination.
At night there are a myriad of celestial objects to observe so the "celestial landfall" procedure is used during the day when the only object available is the sun. From the time of sunrise until an hour later at Howland on July 2, 1937, the azimuth of the sun was 067° true. An LOP derived from observing the sun anytime within this one hour period results in the LOP running at right angles to that azimuth making the LOP run 157° and 337°. Noonan had no choice in the chosen course to use to approach Howland, it was dictated by the location of the sun, and they had no control over that. By turning off to the side of the direct course to Howland, when they determined that they had intercepted the LOP they then turned ninety degrees thereby putting the sun out on the wingtip and establishing themselves on the "course line" running through Howland. Noonan would then take additional observations of the sun to ensure they were staying on course to Howland.
Risky, sure, but that's all you've got before LORAN and GPS and this technique was the standard method used throughout WW2 for finding islands. But not as risky as a surface navigator might think, since you are usually on top of the clouds, and even if some clouds are above you they rarely prevent observations for long periods of time.
----------------------------------------------------------
Discussion continued on NR16020 end of the line - what happened? (https://tighar.org/smf/index.php/topic,548.0.html) thread.
gl
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Gary
5. They flew the 200 or so miles on the LOP towards where they expected Howland to be, didn't spot it, radioed in "we must be on you...", continued on the LOP for 20 to 30 minutes and still didn't spot it so they decided to return along the 337 to 157 course and after they travelled 20 to 30 minutes back to where they had expected Howland to be and still not spotting it radioed "running N and S on the line 157/337" and continued on to the Phoenix Island group (Gardiner?)
But what you are saying doesn't make any sense, You had then aim for a spot 200 miles south-southeast on the LOP on the assumption that the uncertainty, or possible error, in the DR approaches 200 miles. But, they could be off course either to the right or to the left of the the 200 mile offset position along the LOP that you aimed for, so they might actually have intercepted the LOP 200 miles further out to the south-southeast, a total of 400 miles from Howland. You then have them turning left and flying 200 miles along the LOP to the spot where they expect Howland to be. You then have them flying only 44 to 66 miles further prior to turning around but they actually must fly an additional 200 miles to ensure that they have flown far enough to find Howland because of the possiblity that they actually intercepted 400 miles from Howland.
See: https://sites.google.com/site/fredienoonan/discussions/navigation-to-howland-island
gl
Harry, you never responded to my post.
gl
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Gary
Sorry, my reply was the one that went off into the Aether.
Short version:
As they flew the course from Lae to the offset point, taking sightings, the potential drift error would get smaller as the distance remaining after each sighting was reduced. Example, when they reached the halfway point (1200 miles) the error would be 120 miles as opposed to the 240 miles at the start. I assumed that they had a sighting at 0300 hours Howland (1500 (GCT) when they were 400 miles (error 40miles) from the offset point.
They made their turn (Port) onto 157 to 337 and proceeded towards Howland expecting it to be 202 miles (90 minutes at 133 mph) on the LOP. Arriving at the expected location of Howland and not spotting it, they continued on for 44 or 66 miles, covering the potential error. Again not having spotted Howland they circled back and flew 337 to 157 towards the Phoenix Island Group.
The potential drift in that 202 miles could have been 20.2 miles and there might have been a 5 nm (5.75 sm) chart error so they might have been as much as 26sm to the west of Howland's true position. Expecting to see Howland on their nose, it might have been as much as 26 sm off their starboard wing. Could they have seen it?
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Gary
My 0600 time (1800 GCT) was based on an estimate of 2400 sm from Lae to the midpoint of the distance between Howland and Gardiner on the 157/337 line at an estimated "ground" speed of 133.33 mph (400 miles in 3 hours), i.e. 18 hours for the trip to that point.
I'm not sure what time that would have been in the radio room, o530 I suppose.
In a prior post you said:
"The 0614 radio transmission referring to "Am 200 miles out..." was AE reporting her 0600 position on her regularly scheduled 15 minutes after the hour contact."
You have also said that this was when they intercepted the LOP, 200 miles out. But the 0614 Itasca time log of the radio reception of "200 miles out" occurred at 1744 Z, 16 minutes prior to the time you say that they intercepted the LOP 200 miles south-southeast of Howland so it doesn't appear that your theory that they were reporting that interception can be correct.
gl
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Gary
Yes, a good point and one that bothered me and for which I have no explanation. I can only say that the 1800 GCT time was based on an assumption of distance and speed. They might have arrived at 1730 GCT and reported it at 1744 GCT, 0614 Itasca, but that is just a guess.
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Gary
Yes, a good point and one that bothered me and for which I have no explanation. I can only say that the 1800 GCT time was based on an assumption of distance and speed. They might have arrived at 1730 GCT and reported it at 1744 GCT, 0614 Itasca, but that is just a guess.
There are two problems with that. The first is that to go the 2400 SM that you estimated the distance to the 202 SM point on the LOP south-southeast of Howland in only 17.5 hours would have required a ground speed of 137 mph and, taking into account the 25 mph headwind component probably existing at the time, would have required an airspeed of 162 mph.
The second problem is one I pointed out to you a long time ago back in September.
See: https://tighar.org/smf/index.php/topic,452.msg5640.html#msg5640
and: https://tighar.org/smf/index.php/topic,452.msg5646.html#msg5646
Intercepting south-southeast of Howland adds extra distance to the flight. 202 SM out on the LOP where you think they intercepted is at 1° 53' south, 175° 28' west. According to Google Earth, the distance from Lae, located at 6° 44' south, 147° 00' east, to your interception spot is 2609 SM, not the 2400 miles that you calculated. If you work it with the law of cosines your get 2602 SM and if you use the normal navigators spherical trig formula, that I posted before, you get the most accurate distance, 2603 SM, 48 SM longer than the direct distance to Howland and 203 miles more than you figured. To cover 2603 SM in only 17.5 hours requires a ground speed of 149 mph and an airspeed 174 mph. To do it in 18 hours (missing the time to make the "200 miles out" report) would still require a ground speed of 145 mph and an airspeed of 170 mph. All of these values are very unlikely as are the numbers even using your inaccurate 2400 SM distance.
To illustrate again why the interception would have been made to the northwest, assuming the same 202 SM offset, the distance from Lae would have been only 2525 SM, 31 SM less than the direct course to Howland and 79 SM shorter than your route and saving more than a half hour of flying time.
gl
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(http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/37_ItascaLogs/0843.jpg)
if they are on "157 337 LOP" N ES S
could this mean they are on the LOP 157 337 headed E by S
like i have marked on this compass
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To cover 2603 SM in only 17.5 hours requires a ground speed of 149 mph and an airspeed 174 mph.
Gary, could you please expound on the 25 mph difference between ground speed and air speed?
A few other questions if you do not mind:
Were accurate wind aloft measurements taken that day from the Itasca?
Did Earhart receive a report of the winds aloft before she departed Lae?
How did they take these measurements back in the day? Weather balloons?
Thank you in advance.
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(http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/37_ItascaLogs/0843.jpg)
could this mean they are on the LOP 157 337 headed E by S
Besides the explanation that John gave you ("ES" is shorthand for "AND"--sending only the "dits" from the Morse Code for "and" (http://www.deltadx.net/ABCDx/Sections/Introduction.htm)), it is impossible both to "run on the line" 157 337 AND also leave the line in an East by South direction.
Randy Jacobson explains some details of the message in "Log Jam." (http://tighar.org/Publications/TTracks/12_2/logjam.html)
This is my effort to break all of the pieces apart and re-assemble them in a meaningful fashion:
"We are on the line 157 337. XX Will repeat message. We will repeat this on 6210 kcs. Wait."
Received on 3105 kcs, voice quality A3, signal strength S5.
"(?/ KHAQQ transmission: We are running on XX line."
The "North ES South" phrase could be dropped in before or after the word "line."
"We are running on [North and South] line."
The alternative is better English and makes more sense: "We are running on [the] line, North and South."
"Line" appears twice in the log. First it is identified as "line 157 337." Then Earhart says that they are "running on [the] line."
The Itasca operator listens on 6210 kcs, then transmits on 7500 kcs--in code that AE and FN could not understand!--"Heard you on 3105 kcs."
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Gary
Thanks for the critique, two things:
1. Why would they fly a NNW offset? There's nothing up there (unless you include the Japanese mandated islands.
2. Let the leg from Lae to a NNW offset point be A, a leg of a triangle, and B the sffset distance be another leg of the triangle, and C the direct distance Lae to Howland be the hypotenuse. How can the distance A plus B be less than C?
The speed difference between 159 and 162 is less than 2%. A time increase of one-half hour in a trip of 22 hours is about 2.3%. The Electra had a cruising speed capability of 190 mph and a never exceed speed of 202mph so they had plenty of margin to adjust their speed as they progressed along their course, taking sightings and comparing their progress with what they wanted in order to arrive at a LOP around sunrise , which I believe was 0547 Howland.
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Gary
Thanks for the critique, two things:
1. Why would they fly a NNW offset? There's nothing up there (unless you include the Japanese mandated islands.
2. Let the leg from Lae to a NNW offset point be A, a leg of a triangle, and B the sffset distance be another leg of the triangle, and C the direct distance Lae to Howland be the hypotenuse. How can the distance A plus B be less than C?
The speed difference between 159 and 162 is less than 2%. A time increase of one-half hour in a trip of 22 hours is about 2.3%. The Electra had a cruising speed capability of 190 mph and a never exceed speed of 202mph so they had plenty of margin to adjust their speed as they progressed along their course, taking sightings and comparing their progress with what they wanted in order to arrive at a LOP around sunrise , which I believe was 0547 Howland.
Harry, back in September I invited you do draw a diagram so that you would be able see that an intercept to the north-northwest was shorter than an intercept to the south-southeast but you apparently have not done so. See:
See: https://tighar.org/smf/index.php/topic,452.msg5640.html#msg5640
and: https://tighar.org/smf/index.php/topic,452.msg5646.html#msg5646
So to make it easy for you to see this, I am attaching two diagrams that I have drawn for you. Diagram "A" shows the course from Lae to Howland, 2556 SM long, and the courses to intercept points 202 SM out, both to the north-northwest and to the south-southeast. I exaggerated the angles between the course from Lae to Howland and the LOP for clarity. You should be able to see the answer to your question that the distance to the offset point to the north-northwest is shorter than the direct course to Howland and the distance to the other offset point is longer.
Diagram "B" is drawn to scale and you should still be able to see the difference in the two distances.
The reason to fly an offset to the north-northwest is to be able to find Howland, they have no interest in going anywhere else.
No they can't just go a lot faster just to meet your idea that they should intercept the LOP at sunrise, 202 SM out to the right. To go faster requires much more power, it increases as the cube of the airspeed, which then requires full rich mixture (you should know this) so the BSFC goes way up and the specific range goes way down. This means that you get much fewer miles per gallon so you can run out of fuel before you get to your destination.
There is no reason to try to keep to your schedule because you cannot take an accurate sextant reading from an airplane at the time of sunrise because the sun's altitude is actually below zero and the Pioneer octant does not have a scale below zero. Even if it did, Noonan still would not be able to take an accurate sextant observation until the sun was six degrees above horizontal because the tables Noonan was using did not provide correction factors for lower altitudes. It took about one-half hour for the sun to climb above six degrees. The optimum time to reach the LOP was about an hour after sunrise as this would allow about a half-hour period when the sun was high enough for observations so that Noonan could work out his ground speed and the ETA at the LOP.
See: https://sites.google.com/site/fredienoonan/discussions/the-myth-of-the-sunrise-lop
You can also work it out using the law of cosines.
Intercepting to the NNW:
C^2 = A^2 + B^2 -(2 AB cos c)
C^ = 2556^2 + 202 ^2 - ( 2 x 2556 x 202 x cos 79°)
C^ = 2556^2 + 202 ^2 - ( 2 x 2556 x 202 x 0.1908)
C^ = 6533136 + 40804 - ( 197033.948)
C^2 = 6376906.052
C = 2525.254
Intercepting to the SSE:
C^2 = A^2 + B^2 -(2 AB cos c)
C^ = 2556^2 + 202 ^2 - ( 2 x 2556 x 202 x cos 101°)
C^ = 2556^2 + 202 ^2 - ( 2 x 2556 x 202 x -0.1908)
C^ = 6533136 + 40804 + ( 197033.948)
C^2 = 6770973.948
C = 2602.11
The cosine of 101 degrees is a negative .1908 so the second term ends up being a plus which is why this intercept is longer.
gl
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Gary
How nuch of an offset to the NNW do you think they flew to be sure of their turn direction when they arrived at the offset point?
Whar do you think was the reason they missed Howland?
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To cover 2603 SM in only 17.5 hours requires a ground speed of 149 mph and an airspeed 174 mph.
Gary, could you please expound on the 25 mph difference between ground speed and air speed?
A few other questions if you do not mind:
Were accurate wind aloft measurements taken that day from the Itasca?
Did Earhart receive a report of the winds aloft before she departed Lae?
How did they take these measurements back in the day? Weather balloons?
Thank you in advance.
Forcast:
"Winds east south east about twenty-five knots to Ontario then east to east north east about 20 knots to Howland."
See:
http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Worldflight/2ndattemptweather.html
See attached photos. The radiogram is the coded measured weather from Itasca mentioned in in the Tighar document.
Noonan measured 23 knots and it was reported by radio to Lae.
gl
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Gary, Thank you for the detailed weather report information.