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Author Topic: The flight plan, magnetic course, headwinds.  (Read 453196 times)

Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #90 on: January 04, 2012, 11:35:01 PM »

While Gary's theory of the guano mining lights is intriguing, I can't buy it for one simple fact - Fred would have figured out what they were in the same way that Gary figured out that he was looking at a fishing fleet, would he not? Because Fred was a pretty competent navigator. So it would not have been, "Ship in sight ahead."

Even the few "normal" lights on a ship, at night, on the total blackness of the sea, can show up quite well from an aircraft flying at her altitude. And the Ontario would not have been "blacked out," it wasn't wartime yet.

Monty Fowler,
TIGHAR No. 2189 CER
It was reported as both "ship in sight" and "lights in sight." In addition, Cude independently heard the transmission and he said "lights" so he breaks the tie making it "lights" not "ship."

It doesn't take being "blacked out" to be difficult to see a ship at night. There are very few light on deck of ships at night and the ones that are there are very dim.

gl
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #91 on: January 05, 2012, 12:47:58 AM »

If the Myrtle Bank was lighted as described by her Third Mate and sky conditions like-wise as he reported, AE should not have had a problem spotting a ship on a dark sea.  Ontario is less clear, but if the intention of her stationing was to be used as a nav-aid then it is probably reasonable that she too was lighted well enough for sighting.


I think we can all agree on one thing, that no matter how bright a light is it can't be seen if it is sealed in a box made our of steel. A ship's sides are made out of steel so light from inside a cabin can only get out if there is an opening is the steel side of the cabin such as a porthole. See attached diagram. Lights in cabins are normally mounted on the ceiling of the cabin. Light travels in straight lines so if light comes through an opened porthole it will only be seen  by someone in a position where he can look in a straight line through the porthole and see the light bulb. With the porthole mounted at a  lower height than the ceiling then the light can only be seen by someone whose eye is even lower than the porthole and the light cannot be seen from an airplane.

The machinery spaces of a steamship are located in the center of the ship and at the very lowest level of the hull, this is about four or five decks down. It is common to have a skylight at the top of the superstructure to admit light and are often opened for ventilation. On ships I have been on, these skylights are about 8 to 10 feet long and about 4 feet wide. See attached diagram. The light from a lamp down in the engine room shinning up through the skylight can only shine basically straight up and this light could only be seen if a plane passed almost directly over the ship, an unlikely event.

gl
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #92 on: January 05, 2012, 03:16:18 AM »

ANY lights on a ship at night show up extremely well, which is why light discipline was crucial during wartime.  Even a lit cigarette could be seen for miles.
Yep from the height of a raised periscope.

gl
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Heath Smith

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Re: The flight plan, magnetic course, headwinds.
« Reply #93 on: January 05, 2012, 04:33:07 AM »

Quote
So, either you are right, that one candle can be seen at 30 miles or the government is right that one candle is only visible at about one nautical mile, my money is on the government's engineers on this one.

From your posts, the government was attempting to establish a mathematical model for the average perception at night so that they could establish guidelines, not the limits of human perception.

Here is one study (1987) that also contains WW II night vision studies that might make for an interesting read. While I have not read the entire document, it states that a single candle is visible from 17 miles away:

http://www.nap.edu/openbook.php?record_id=1037&page=26

If you want to debate the limits of human vision that is fine however we are not even discussing a ship with a single candle flame on deck, we know little of the lighting on the Ontario, it is all pure speculation. As I stated before, the assumption that the Ontario had only Fresnel running lights is a worst case scenario. Little to nothing is known about any of the lights (Ontario, Myrtle Bank, Nauru) in question that night.
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JNev

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Re: The flight plan, magnetic course, headwinds.
« Reply #94 on: January 05, 2012, 10:27:38 AM »

...then I guess we wasted alot of hope and effort telling service people to go to trouble blacking out ships and not smoking on deck, etc.

I agree with Heath - all the cited standards are all about establishing something approaching guaranteed performance to help mariners, etc. in all weathers.  They have nothing to do with what can be perceived under good conditions, etc. and do nothing to prove that a candle cannot be seen at great distance, etc.  The point is we can perceive light on a dark ocean from a darkened cockpit quite well.

As to how ships emit light, I appreciate your efforts, Gary - but in my experience they are simply not credible.  I've seen too many ships at sea for too many years of my life here on the coast and in other places to buy any of it.  There's far more 'casual' light emitted by ships at sea than you are crediting - even with 'blacked-out' bridges (field of vision from there can have little to do with what alight below or behind, for example; bridges tend to be placed where the weather glass is open to dark sea...).

In one of history's great tragedies, in her throws of death Titanic spotted the SS Californian as it drifted for the night in the distance (some now say it could have been the Samson*).  Californian also saw what was likely Titanic - no mystery there, the dying ship was ablaze with every light she had until the generators failed.  What is telling to me, if no surprise, is that Titanic saw the distant, 'sleepy' ship on the horizon...

* It's apparently now popular in historic recounting to go 'PC' to allow for revisionism in case someone should feel unfairly impuned - 'perhaps' William DID conquer... etc.  Yuck.  Californian is probably our loose-goose in this case, but if I were her master I wouldn't want that on my tombstone either.

LTM -
- Jeff Neville

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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #95 on: January 05, 2012, 01:39:26 PM »

well.

As to how ships emit light, I appreciate your efforts, Gary - but in my experience they are simply not credible.  I've seen too many ships at sea for too many years of my life here on the coast and in other places to buy any of it.  There's far more 'casual' light emitted by ships at sea than you are crediting - even with 'blacked-out' bridges (field of vision from there can have little to do with what alight below or behind, for example; bridges tend to be placed where the weather glass is open to dark sea...).


It sound like you are talking about observing ships from the shore, not from a plane.
What kind of ships are you talking about, 1930s era freighters and navy tugs or the floating hotels of today with every cabin having its own balcony and sliding patio doors and logo lights shinning on the stack? And your example of the Californian is also an observation made from sea level (on the way to being below sea level) on the Titanic.

gl
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JNev

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Re: The flight plan, magnetic course, headwinds.
« Reply #96 on: January 05, 2012, 02:05:41 PM »

well.

As to how ships emit light, I appreciate your efforts, Gary - but in my experience they are simply not credible.  I've seen too many ships at sea for too many years of my life here on the coast and in other places to buy any of it.  There's far more 'casual' light emitted by ships at sea than you are crediting - even with 'blacked-out' bridges (field of vision from there can have little to do with what alight below or behind, for example; bridges tend to be placed where the weather glass is open to dark sea...).


It sound like you are talking about observing ships from the shore, not from a plane.
What kind of ships are you talking about, 1930s era freighters and navy tugs or the floating hotels of today with every cabin having its own balcony and sliding patio doors and logo lights shinning on the stack? And your example of the Californian is also an observation made from sea level (on the way to being below sea level) on the Titanic.

gl

From shore, sea and air.  Anything from small fishing and shrimp boats through 'modern' tramps (as opposed to 1937, for sure) and up to large container ships.

I don't find so much disadvantage from the air for some reason - but admittedly cannot go back to 1937 and take a look; that said, ships have had lots of lighting capabilities for a long time, to wit, again, Titanic, Californian, etc.  I have a hard time dismissing that their lights somehow evaded detection from above (and alas, have no report to give - there were no mid-Atlantic airplanes present in that day...).  :P

What am I missing here -

Why so much concern over whether AE saw a ship or just 'lights'?  How far from land would Ontario or Myrtle Bank have been when the spotting would have occurred? 
Could AE and FN have misplaced themselves so badly under 'fine conditions' as to have mistaken the two (ship vs. land lights)?
Where would it have put the flight at that report if land lights?  Just approaching Nauru and her guano mines?
What would the impact be to the course / fate of the flight if so?

Sounds like something to consider.

LTM -
- Jeff Neville

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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #97 on: January 05, 2012, 03:01:27 PM »

Why so much concern over whether AE saw a ship or just 'lights'?

It affects reconstruction of the path of the flight in the middle of night.

Quote
How far from land would Ontario or Myrtle Bank have been when the spotting would have occurred? 

LTM,

           Marty
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JNev

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Re: The flight plan, magnetic course, headwinds.
« Reply #98 on: January 05, 2012, 05:32:15 PM »

Thanks Marty - that illustration helps a great deal (just what I'd been wanting to see in fact).

Looking at the whole 'fix' thing from Nukumanu through Ontario, Myrtlebank and Nauru and how AE tended to communicate I am left confounded that she was constantly ambiguous in her reports.  It's impossible to assign a position at Ontario, Myrtlebank - or Nauru (WAY north) based on time.  Was it her habits that were to blame, or something else? 

In re-reading some of Gary's posts I believe I understand his thinking on Nauru more clearly: I believe he offered the possibility of an intentional 60 mile offset to north (at end of course) to allow a LOP intercept and then a known track southeast to attain Howland. 

We don't know that FN used an offset at all, but the idea does make sense for the reasons Gary has stated and is within the conventions he cited for oceanic landfall.  However, if it was Nauru's lights that AE spotted 'ahead', she must have been another 70 miles or so north, at mid-course, of what would become at the end the intended 60 mile offset (presuming for a moment that an offset was used) - and making good speed.  Interesting.  Maybe some really weird winds and blind skies could get someone like FN into that fix, but hard to say.

As to AE's habits and my confoundment -

Position at WHAT time; HEADING on LOP; 'LOW FUEL' meaning 'limited loiter here and then have to bug out', or 'about to splash'?  We're left with so many tattered ends from poor AE's efforts with the radio it's not hard to visualize the flight coming to grief - and now it's even harder to reconstruct 75 years later.  She was probably accustomed to answers from the ground too, and none would come this time - the most crucial she ever needed.

For his part, FN apparently was stuck with nothing more than compass, watch, octant - and AE.  I prefer to have doubts that he ever let them slip 100 miles north of course; I don't doubt that he may have been reduced to dead-reckoning for too many hours, and that by the time the sun came up AE's execution over that distance had compromised landfall - can happen.  That could explain why the one LOP we know of was all that we heard of: never got a chance to establish any kind of fix (until landfall at Gardner, of course...  ;))

But FN - and AE could have been stuck with something else, too.  I hate to say it, but I've begun to think about the reason for FN's firing from Pan Am... very ugly of me.  Would AE struggle to cover up any problems she may have had with him, even to the point of keeping relatively cool as she tried to work a LOP to some sort of landfall at the end of things?  What's missing is any reliable position reports after 0718Z -

WHY?
- Jeff Neville

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« Last Edit: January 05, 2012, 08:27:27 PM by Jeff Neville »
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JNev

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Re: The flight plan, magnetic course, headwinds.
« Reply #99 on: January 05, 2012, 08:09:30 PM »

Actually apparently I was wrong about Noonan - at least one account says he resigned after conflict over duty times and other related concerns at Pan Am.  I thought he had been fired.

But I still wonder why the dearth of news from the back of NR16020.  On the first flight he apparently had AE execute some well-determined navigation exercises, like adjusting airspeed to arrive at a fix at a certain time and tracking a DF steer with offset, etc.  Maybe Noonan was proving his own mettle then, or I suspect more maybe he was seeing what AE might handle.  Paul Mantz was of course also in the cockpit...

But with all those colorful skills, why no more about fixes, etc. through AE to Itasca, etc.?  Something still seems to be missing.

LTM -
- Jeff Neville

Former Member 3074R
 
« Last Edit: February 08, 2016, 08:06:27 AM by JNev »
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Irvine John Donald

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Re: The flight plan, magnetic course, headwinds.
« Reply #100 on: January 05, 2012, 10:01:20 PM »

Actually apparently I was wrong about Noonan - at least one account says he resigned after conflict over duty times and other related concerns at Pan Am.  I thought he had been fired.

But I still wonder why the dirth of news from the back of NR16020.  On the first flight he apparently had AE execute some well-determined navigation exercises, like adjusting airspeed to arrive at a fix at a certain time and tracking a DF steer with offset, etc.  Maybe Noonan was proving his own metal then, or I suspect more maybe he was seeing what AE might handle.  Paul Mantz was of course also in the cockpit...

But with all those colorful skills, why no more about fixes, etc. through AE to Itasca, etc.?  Something still seems to be missing.

LTM -

That's what I have been saying Jeff. It's as though FN wasn't with her.  AE's radio messages have no hint of there being a course correction of any type. Large or small.  Ego?  Could be she didn't want to say there was a correction.  But it didn't sound like that.  The radio signal research suggests they were further from Howland than everyone thought but a fix wouldn't lie unless calculated wrong. This being probably the hardest leg should mean AE and FN should have been on their toes. FN should have been all over fixing any drift or course deviation by sloppy flying. That's FN's sole function on this whole trip. It's what he did for Pan Am, as a career navigator and as a teacher. How could he let AE stray so far off course?  Was he incapacitated?  Asleep?  Sorry but I think they navigated to within a few miles of Howland as planned and then they just didn't see the island.  Why do we assume a navigation error?  The recent Radio signals and antenna studies "suggest" the aircraft was further away than planned but nothing else does.  When I say "suggest" I do not want to detract from Bob Brandenburgs good work. Even Bob has caveats in his study.
Respectfully Submitted;

Irv
 
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #101 on: January 05, 2012, 10:44:23 PM »

In re-reading some of Gary's posts I believe I understand his thinking on Nauru more clearly: I believe he offered the possibility of an intentional 60 mile offset to north (at end of course) to allow a LOP intercept and then a known track southeast to attain Howland. 

I cannot deny that possibility.

It is a possibility.

It's what Gary would have done.

It is not unreasonable.

The sole contemporary evidence we have about what they did is in the last message, which contains the "We are flying line North and South." 

To my (admittedly unprofessional) ear, that sounds as though they were not confident whether Howland was north or south of the point at which they crossed the advanced LOP.

Quote
She was probably accustomed to answers from the ground too, and none would come this time - the most crucial she ever needed.

No.  She had never been guided in to an airport through RDF-and-transmissions where she had to handle the direction finding and the radio.  She was accustomed to broadcasting news updates at regular intervals and listening on her receiver at other intervals.  She was not accustomed to having a back-and-forth conversation as pilots do today.

Quote
But FN - and AE could have been stuck with something else, too.  I hate to say it, but I've begun to think about the reason for FN's firing from Pan Am... very ugly of me.  Would AE struggle to cover up any problems she may have had with him, even to the point of keeping relatively cool as she tried to work a LOP to some sort of landfall at the end of things?

What's missing is any reliable position reports after 0718Z -

WHY?

Who knows?  Maybe Fred a heart attack and AE didn't want to worry folks on the ground.

Maybe a bird flew through the window at 2013.

Maybe AE was pregnant and suffering from morning sickness the whole flight.

Maybe Fred had a mystical experience, foresaw that they would die, and just went into a trance state.

Maybe they were on a secret spy mission and all of the pre-recorded broadcasts were sent from the Ontario.

Maybe they didn't think precise position reports mattered.

Maybe they had migraines and couldn't read the charts.

Once you decide to start using your powers of ESP, the sky is the limit for what you might find floating into your head.
LTM,

           Marty
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #102 on: January 06, 2012, 02:21:36 AM »

Is there evidence that the lights would be on at the Guano mines?  Was it a 24/7 operation or was there down time and thus 'lights off'?

BTW if AE/FN thought the Myrtle Bank was the Ontatrio how far out would that put them on the final day?
Yes, see attached radiogram.

gl
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #103 on: January 06, 2012, 03:48:19 AM »

Why so much concern over whether AE saw a ship or just 'lights'?

It affects reconstruction of the path of the flight in the middle of night.

Quote
How far from land would Ontario or Myrtle Bank have been when the spotting would have occurred? 
I have attached another chart showing two options for flying from the position reported in the 0718 Z radio transmission to Howland. Flying directly to Howland is 1,716 SM while over flying Nauru to Howland is 1,746 SM, only 30 SM longer, about 12 minutes more flying time, about eight gallons of gas. If Noonan had already been giving thought to a landfall approach to Howland, with the interception to take place northwest of Howland, then flying over Nauru would be even less out of the way since it would be more ON the way to the interception point. In this case it would only be 10 SM longer, 4 minutes flying time and about 2 gallons of gas.

As I posted before, people are too wedded to the line drawn on the chart connecting Lae to Howland and put way too much emphasis on trying to stay exactly on that line than it deserves. I have shown mathematically that there is very little penalty in deviating even great distances from the direct line and, if the deviation allows you to pick up even a slight tailwind, may actually result in a shorter flight time and less fuel consumed. I have also posted that the two charts we have that were actually used by Noonan on the Earhart flight, one from Oakland to Hawaii and the second from Natal to Dakar, show that Noonan didn't come anywhere close to staying on the preplanned direct line. In spite of this evidence to the contrary, people still are in love with that straight line from Lae to Howland. However, we don't have Noonan's chart for this flight (he took it with him) so we don't know exactly what lines HE drew on HIS chart for this flight. All we have is a planning strip chart NOT drawn by Noonan but drawn by Clarence Williams many months earlier when the planned route was in the opposite direction. The navigation FROM Howland TO Lae was a much different navigational proposition because the target was located on a large land mass itself and, even before arriving at New Guinea, they had the island of New Britain on their right side and they also had to cross the entire chain of the Solomon Islands that stretches a thousand miles across their course line, very hard to miss that, it was like aiming at a continent. It would be a much easier task finding all that land and then following it to Lae. With all this land to aim at Earhart didn't even really need a navigator since dead reckoning would have been entirely sufficient for that route. (I have attached a second chart showing this situation.)

Going from Lae to Howland required finding a very small island at the end of a long over water leg, a much more difficult navigational task. Noonan could then be forgiven, after looking at William's strip chart, if he decided on a different route than Williams had chosen. Plus Noonan had a new piece of information that Williams didn't have (and would have meant nothing to Willilams even if he did) that Nauru had extremely powerful lights (think of stadium lights) used for working the guano mines all night. Noonan knew that Ontario was supposed to be on station but there would have been some uncertainty about its effectiveness, it could have had a problem, run out of fuel, or been off station at the time that Noonan would be flying over the ship. If Noonan wanted to use it as a check on his navigation up to that point then there would be uncertainty in the derived position because the ship might not be exactly on the assigned station. Earhart had also been informed that Ontario did not have radio capability to hear her transmissions or to communicate with her directly. In order for Ontario to start transmitting a homing signal it needed to be informed that Earhart was on the way and Noonan knew that he would have to trust others, not under his control, to get that message to Ontario and he also knew that he would not have any confirmation that the message had been delivered to Ontario, he would just have to cross his fingers. But looking at the new information about Nauru he knew that the island would be exactly in the same place where it was supposed to be and the lights of the Ontario, no matter how powerful, could never compete with the lights of Nauru. He could feel much more certain about spotting those lights, and from a greater distance, than he could feel about spotting the Ontario.

And they were not mutually exclusive choices. If he started receiving the radio beacon from Ontario then he could change his plans and head for Ontario, if not, then he still had the certainty of finding Nauru. After overheading Ontario he could still fly over Nauru for a precise navigation check if he felt he needed it.
So taking all of this into account, spending eight gallons and only 12 minutes to provide extra certainty in the navigation would be a good choice to make and Noonan was a good navigator.

gl
« Last Edit: January 15, 2012, 01:33:04 AM by Gary LaPook »
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Heath Smith

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Re: The flight plan, magnetic course, headwinds.
« Reply #104 on: January 06, 2012, 04:21:40 AM »


AE did send a telegram out stating that they were running late and that she wanted to inform the Ontario. If they had devised an alternative route by that point in time I am sure they would have advised someone on the ground or via telegram. If you are making such a risky journey chances are you would want to tell someone where you are headed in case you do not make it and they need to come searching for you. In that case it would be best to stick to the plan that everyone knew.

One piece of information would tend to contradict a Nauru fly over, the radio logs. First, at 10:30 GMT, they would have still been on an approach to Nauru even assuming 150 mph from the last known position. The 10:30 GMT report from Nauru stated "fairly strong signals, speech not intelligible". At 14:10 GMT the Itasca Bridge reported hearing Earhart, at 14:15 GMT the Itasca radio room reporting hearing her. There was not report from Nauru about the these transmissions suggesting that the Electra was already out of radio range. This would tend to suggest that at 10:30 GMT they were closer to Nauru than they were at 14:10, 40 minutes later. I suppose if you tossed in a radio doughnut hole theory this might still be plausible.
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