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Author Topic: The flight plan, magnetic course, headwinds.  (Read 473562 times)

Bruce Thomas

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Re: The flight plan, magnetic course, headwinds.
« Reply #180 on: January 08, 2012, 12:01:30 PM »

Maybe off-line ... would be more appropriate ...

Amen, Jeff!   :D

The private message feature of the Forum is a wonderful healing aid ... I've found it second only to self-imposed silence to maintaining my equilibrium. 

My late father was a ham radio operator (for 77 years) but even though I'd fall asleep as a kid listening to him exchanging pleasantries in CW to hams around the world (we lived in a rare DX location in the Caribbean not long after WWII) the bug never bit me (you can slap me hard for that pun).  I never could understand how he could listen so patiently to some other ham's lengthy monologues and then, when the QSO was finished, sign off and explain how whatever that guy claimed to be true was so patently wrong.  (One of those fellows has been mentioned on this Forum, a colorful individual -- with another anecdote about AE remembered from his childhood -- who I met when he visited Dad on that Caribbean isle; a man whose many stories Dad especially expressed opinions about later.)  But now I think I've mastered Dad's m.o., and I can now channel his serenity.

But another method of "staying clam" that I have found to be effective is to call up one of the many months' worth of the old AE Forum and skim through its entirety.  Hours whiz by and my eyeballs begin to glaze over.  And it's amusing to see how many of our current musings are just repeats of what has been hashed over 10-15 years ago.  And there were fireworks back then, too -- self-proclaimed expertise, bombasts, and egregious name-calling.  I can especially recommend December 2003 -- the high-water mark for outlandish posters, including Bonnie, John, Don, and Carol.  ;D  (A helpful hint:  when looking at one of those files that does not wrap at the right-hand margin, copy and paste the entire thing into a temporary word-processor document for easier reading.)

This station is now going QRT again.   

LTM,

Bruce
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #181 on: January 08, 2012, 12:23:47 PM »

Well, not so fast.

All of my research confirms that there was no telephone service, either by undersea cable or by radiotelephone, from Lae to the outside world in 1937. Even local radio telephone service in New Guinea did not come on line until 1939.

What is the source of the image?

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It appears the only evidence that telephone service was available between Lae and the U.S. is the story printed in the Herald Tribune that, it is claimed, had been telephoned by Earhart in Lae to the newspaper.

Yes.  That seems to be Ric's reasoning, as far as I can tell.  He quotes the Tribune in the footnotes for Finding Amelia.

From the old Forum:

Date: Wed, 2 Feb 2005 15:43:36
From: Ric Gillespie
Subject: Phone service in New Guinea

On June 30, 1937 the New York Herald Tribune ran an article headlined "Amelia Ready to Fly to Howland Island".  The article is a first-person account by AE of her flight to Lae from Darwin and her plans for departing for Howland.  Under the headline is the notation "by telephone to the Herald Tribune".

I have always been under the impression that there was no telephone service from Lae to the United States.  If there was phone service it's hard to understand why Earhart communicated to Putnam from there by cablegram unless it was purely a matter of expense ( the phone call to the Trib was certainly paid for by the paper). Earhart and Putnam did talk by phone when she was in Karachi, India and again when she was in Bandoeng, Java.

Elgen Long, on page 178 of his book, says that "Earhart asked if she could make a telephone call to the United States and was told there was no telephone service from New Guinea."  Unfortunately, he cites no source for the statement. If Long is right then the Herald Tribune article is very strange.


I've started a table of the message traffic to and from Lae, putting the entries in chronological order (where possible) and making some guesses otherwise. 

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The last chapter of Earhart's book, Last Flight, reprints the two stories printed in the Herald Tribune. The second part of the chapter, beginning with "'Denmark's a prison...'," is the newspaper story clearly sent by radiogram. We know this because we can find this radiogram at the Purdue site. This story was printed in the July 2, 1937 edition of the newspaper. The first half of the chapter beginning with "After a flight of seven hours..." was the earlier story sent to the newspaper and th is story is the one claimed to have been telephoned by Earhart. We can't find a copy of a radiogram for this story but I have found a telegram from the Herald Tribune to Putnam acknowledging the receipt of this story and that first story was clearly sent by radiogram. This telegram is dated June 29 so it cannot be referring to the radiogram for the second story because the radiogram for the second story did not arrive until July 2nd. The June 29th acknowledgment telegram states;

"LAE DISPATCH ARRIVED LATE TONIGHT..."

The word "DISPATCH" obviously did not refer to a telephone call.

What is "obvious" to one may not be obvious to another.

Since that same telegram says "LAE DISPATCH ARRIVED LATE TONIGHT. THINK WE HAVE SOLVED CABLE CREDIT DIFFICULTY," it might be referring to the preceding telegram, address both to Putnam and the Tribune, which read, in part: "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY."  The Tribune telegram might mean, "We received the telegram from Earhart that asked us to arrange credit for her."  In other words, Putnam does not have to take any further action on that particular request made in the telegram that was sent to both parties.

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"Dispatch" was the commonly used word in the newspaper industry to mean "a story sent in by a correspondent." The dispatch was received late at night on June 29th but early enough for this telegram to be send to Putnam, still on the 29th. So let's say it arrived around 10:00 p.m. New York time. Lae is 15 hours ahead of New York so the message was sent some time prior to 1:00 p.m. in Lae on June 30th, the day after Earhart had arrived in Lae.

Yes, that's possible.

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I have attached a copy of this telegram. I have also attached a copy of the radiogram containing the second story showing it was received "VIA RCA" from Lae NG (RCA= Radio Corporation of America, an obvious radiogram) on July 2nd at 3:48 in the morning.

I have put those telegrams in my table, along with links to the Purdue archive, so that folks can see where you got them (I presume you got them from Purdue).

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This appears to be another case (all too common in scholarship, and  well represented in writings about Earhart) of the first person writing a story getting and it wrong and then everyone else just copying off of his paper without going back to the source documents themselves. It looks like decent research because they include cites to their sources, and they usually cite to the original document cited in the secondary source that they are actually using, not revealing that they are only using a secondary source. But since the secondary source got it wrong the error propagates throughout the literature, like a snowball rolling downhill. (TIGHAR is to be congratulated on its instance of references to the original documents.)

Yes, I rely on secondary sources that I consider trustworthy.  The case might be settled decisively by examining the archives for the Tribune, if they exist, and finding the missing source of the first material from Earhart in Lae.

Of course, I should be happy that you may have shown that there was no "telephone" link from Lae to New York, despite the by-line in the Tribune.  It's one more nail in the coffin of the Gore anecdote, which is, I believe, where this all began.
LTM,

           Marty
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #182 on: January 08, 2012, 04:08:29 PM »


What is "obvious" to one may not be obvious to another.

Since that same telegram says "LAE DISPATCH ARRIVED LATE TONIGHT. THINK WE HAVE SOLVED CABLE CREDIT DIFFICULTY," it might be referring to the preceding telegram, address both to Putnam and the Tribune, which read, in part: "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY."  The Tribune telegram might mean, "We received the telegram from Earhart that asked us to arrange credit for her."  In other words, Putnam does not have to take any further action on that particular request made in the telegram that was sent to both parties.
The problem with that explanation is that the "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY" radiogram arrived at 5:53 p.m. which I don't think anyone would describe as "ARRIVED LATE TONIGHT. Prior to 6:00 p.m. is normally called "afternoon" not "night" and certainly not "late night." The confirmatory telegram sent out later on the night of the 29th did refer to this radiogram but also to the "DISPATCH" that arrived later, "late night". They apparently arranged credit in response to the 5:53 p.m. telegram that allowed Earhart to send the "dispatch" later that day.

Earhart sent only two "dispatches" to the newspaper, the one in dispute and the second one that was printed several days later. The confirmatory telegram referred to a "dispatch" sent by Earhart from Lae on June 30th, (Lae date and time.) The story printed in the Harold Tribune had the dateline "Lae, New Guinea, June 30th."

I rest my case.

What we probably have here is just a simple typesetter's error setting "telephone" instead of the correct "telegraph." These types of errors are common enough today with computerized typesetting and it was even more common on the old linotype machines, (though it was cool watching the hot slugs of lead type come out of the machine.)

gl
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Heath Smith

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Re: The flight plan, magnetic course, headwinds.
« Reply #183 on: January 08, 2012, 06:21:21 PM »

I am seeking out opinions about the approach to where AE and FN thought Howland was. The following questions are based on the assumption that DR was used and FN was not able to obtain a celestial fix.

1) Assuming they were at 8,000ft for the long haul to Howland, when would they begin their decent? I thought I had read a recommendation, maybe in the 487 report, that a descent should begin at 150 to 100 miles out and power should be maintained during the descent. Can anyone tell me otherwise? Do we have an historical info on how AE handled approaches in the past with specific values for rate of descent or speed?

2) At 19:12 GMT, AE stated "we must be on you". Do we suppose that as soon as the clock was a ETA zero that they stopped in their tracks and started circling or was this perhaps sometime after ETA was zero, some number of miles later? Would they continue on the same heading to see if the Island came in to view? Could the 19:12 GMT report have been transmitted when they decided it was time to give up on the flight line having passed up where they thought Howland was some time ago?

3) If they did give up on finding Howland on the flight path, would they back track (do a 180 turn) to where they originally thought Howland was or would they just begin a search pattern where found themselves after giving up?

4)  How long do you suppose they sat their circling before taking some action? They searched for a full hour before the final transmission at 20:13 GMT. Would they have been aware of the 10% worst case error in the DR and immediately headed North and South on the 157/337 LOP to determine if they were North or South of Howland?

5) Why choose the 157/337 line anyway? I am not seeing the logic for following this LOP unless their line of approach that was pre-determined ahead of time was 90 degrees out from this line.

Thank you in advance.

« Last Edit: January 08, 2012, 07:23:13 PM by Heath Smith »
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #184 on: January 08, 2012, 06:52:12 PM »


Since that same telegram says "LAE DISPATCH ARRIVED LATE TONIGHT. THINK WE HAVE SOLVED CABLE CREDIT DIFFICULTY," it might be referring to the preceding telegram, addressed both to Putnam and the Tribune, which read, in part: "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY."  ...

The problem with that explanation is that the "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY" radiogram arrived at 5:53 p.m. which I don't think anyone would describe as "ARRIVED LATE TONIGHT.

The man who said "ARRIVED LATE TONIGHT" is Hill, who is located in NYC, and for whom 5:53 PM would be 8:53 PM.  I don't know how quickly the Oakland, California, office of the Tribune could relay the telegram to NYC, so it may have come to NYC later than 8:53 PM.  I've dated Hill's telegram 29-06 PM EST, but I couldn't see a time stamp in it for when it was sent.

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Prior to 6:00 p.m. is normally called "afternoon" not "night" and certainly not "late night." The confirmatory telegram sent out later on the night of the 29th did refer to this radiogram but also to the "DISPATCH" that arrived later, "late night". They apparently arranged credit in response to the 5:53 p.m. telegram that allowed Earhart to send the "dispatch" later that day.

I don't think that's right.  The credit is mentioned in the "dispatch received" telegram.  I believe the credit let AE send the 9-page telegram that is available at Purdue, 01-07 2200A? Lae (I can't make heads nor tails out of the "2200A").  The clue is in the heading: "FAB55 VIA RCA=F NG 570 1/100 PRESS COLLECT 1 2200A."

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Earhart sent only two "dispatches" to the newspaper, the one in dispute and the second one that was printed several days later. The confirmatory telegram referred to a "dispatch" sent by Earhart from Lae on June 30th, (Lae date and time.) The story printed in the Harold Tribune had the dateline "Lae, New Guinea, June 30th."

Have you got a scan or a link to the original newspaper article?  The way I read the footnote in Finding Amelia, the article was published in the 30 June edition of the Tribune.

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What we probably have here is just a simple typesetter's error setting "telephone" instead of the correct "telegraph." These types of errors are common enough today with computerized typesetting and it was even more common on the old linotype machines, (though it was cool watching the hot slugs of lead type come out of the machine.)

Yes, it could be a mistake.  Another possibility is that there might have been a patch from Lae to the mainland via Nukulau, if there was a telephone line from Lae to Nukulau.  It wouldn't be the first time in the story that folks scrambled to get something special for "Miss Earhart."

You have rested your case, but the jury is still out.   ::)

Marty
LTM,

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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #185 on: January 08, 2012, 09:45:02 PM »


Since that same telegram says "LAE DISPATCH ARRIVED LATE TONIGHT. THINK WE HAVE SOLVED CABLE CREDIT DIFFICULTY," it might be referring to the preceding telegram, addressed both to Putnam and the Tribune, which read, in part: "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY."  ...

The problem with that explanation is that the "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY" radiogram arrived at 5:53 p.m. which I don't think anyone would describe as "ARRIVED LATE TONIGHT.

The man who said "ARRIVED LATE TONIGHT" is Hill, who is located in NYC, and for whom 5:53 PM would be 8:53 PM.  I don't know how quickly the Oakland, California, office of the Tribune could relay the telegram to NYC, so it may have come to NYC later than 8:53 PM.  I've dated Hill's telegram 29-06 PM EST, but I couldn't see a time stamp in it for when it was sent.

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Prior to 6:00 p.m. is normally called "afternoon" not "night" and certainly not "late night." The confirmatory telegram sent out later on the night of the 29th did refer to this radiogram but also to the "DISPATCH" that arrived later, "late night". They apparently arranged credit in response to the 5:53 p.m. telegram that allowed Earhart to send the "dispatch" later that day.

I don't think that's right.  The credit is mentioned in the "dispatch received" telegram.  I believe the credit let AE send the 9-page telegram that is available at Purdue, 01-07 2200A? Lae (I can't make heads nor tails out of the "2200A").  The clue is in the heading: "FAB55 VIA RCA=F NG 570 1/100 PRESS COLLECT 1 2200A."

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Earhart sent only two "dispatches" to the newspaper, the one in dispute and the second one that was printed several days later. The confirmatory telegram referred to a "dispatch" sent by Earhart from Lae on June 30th, (Lae date and time.) The story printed in the Harold Tribune had the dateline "Lae, New Guinea, June 30th."

Have you got a scan or a link to the original newspaper article?  The way I read the footnote in Finding Amelia, the article was published in the 30 June edition of the Tribune.

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What we probably have here is just a simple typesetter's error setting "telephone" instead of the correct "telegraph." These types of errors are common enough today with computerized typesetting and it was even more common on the old linotype machines, (though it was cool watching the hot slugs of lead type come out of the machine.)

Yes, it could be a mistake.  Another possibility is that there might have been a patch from Lae to the mainland via Nukulau, if there was a telephone line from Lae to Nukulau.  It wouldn't be the first time in the story that folks scrambled to get something special for "Miss Earhart."

You have rested your case, but the jury is still out.   ::)

Marty

According to contemporary Australian newspapers, they landed at Lae at 2:56 p.m. on the 29th, not much time to do any sightseeing that day since sunset was less than three hours later and they had to put the plane to bed first, check into the hotel etc., and she reported some sightseeing in the first dispatch.

I looked at your table of transmissions. Looking at the disputed dispatch it could not have been sent on the 29th. Read the story as reprinted in Last Flight and you will find her saying "We stayed at a hotel...", past tense, not a present tense, "We stay at a hotel..." or "We are staying at a hotel..." It is clear that this was sent after spending a night in the hotel in Lae so it must be June 30th, not June 29th. 

The "arrange credit" telegram was sent out at 6:30 a.m. Lae time on June 30th. She had already sent a telegram to the Itasca at 6:15 a.m.


Let's look at a time line that would allow the confirmatory telegram to be referencing only the "arrange credit" telegram. She would have had to have telephoned the story in to the newspaper very early on the morning of June 30th prior to her sending out the "arrange credit" telegram at 6:30 a.m. Who paid for the telephone call? And why incur the expense of sending a telegram later to arrange credit when she could have just asked for that while on the telephone? You are obviously reading "ARRANGE CREDIT IF TRIBUNE WISHES MORE STORY. " as more story after the one I already phoned in from Lae and I am reading it as more story period, the dispatch from Darwin is all they are going to get unless they pony up some money.

My reading of these telegrams is this. Earhart is out of money and cannot send a dispatch to the paper or make a phone call. She sends out the request to "arrange credit"  at 6:30 a.m. She goes sightseeing and works that into her planned dispatch. She is informed later that morning or early afternoon that credit for collect telegrams to the newspaper has been arranged so she sends her dispatch at that time which arrives "LATE TONIGHT" on the 29th either in New York or in Oakland. At 11:32 p.m. on the 29th Hill sends a night letter to Putnam confirming receipt of her dispatch and containing the words "THINK WE HAVE SOLVED CABLE CREDIT DIFFICULTY" most likely as evidenced by the fact that RCA and Western Union had accepted her dispatch and had delivered it to the Herald Tribune office. This is a common construction as in "I think I have solved my electrical problem ...the lights just came on."
If the request to arrange credit had only arrived "LATE TONIGHT" how could Hill have solved the "CABLE CREDIT DIFFICULTY" prior to sending the telegram to Putnam at 11:32 p.m.? Who did he talk to? How did he put up cash if that was required that late at night? If the telegram to Putnam only referred to the credit situation then why does it mention the "dispatch?" I believe the credit arrangement allowed her to send both of the dispatches from Lae.

By Nukulau in the Fijis, I take it you are talking about a cable landing in Suva. There were no telephone cables to Suva either from the U.S or from New Guinea in 1937, see chart of cables. The cable going to Suva was a telegraph cable, not a telephone cable. The first Trans-Atlantic telephone cable was laid in 1956 and the first Trans-Pacific telephone cable did not arrive until 1964. There were no telephone lines out of Lae to anywhere, which is why it was a big deal when local radiotelephone links were established in 1939.



gl
« Last Edit: January 10, 2012, 02:05:11 AM by Gary LaPook »
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #186 on: January 09, 2012, 01:11:25 AM »

I am seeking out opinions about the approach to where AE and FN thought Howland was. The following questions are based on the assumption that DR was used and FN was not able to obtain a celestial fix.

1) Assuming they were at 8,000ft for the long haul to Howland, when would they begin their decent? I thought I had read a recommendation, maybe in the 487 report, that a descent should begin at 150 to 100 miles out and power should be maintained during the descent. Can anyone tell me otherwise? Do we have an historical info on how AE handled approaches in the past with specific values for rate of descent or speed?
You can begin your descent whenever you want to however to get maximum range you want to do a long slow descent which is why that advice is in report 487. More important is getting an observation of the sun when getting close to the LOP which would require (if there were clouds below) delaying the decent until about 10 to 15 NM short of the LOP and slowing down as necessary. They could actually wait until intercepting the LOP and then spiral down through the clouds to ensure accurately being on the LOP.
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2) At 19:12 GMT, AE stated "we must be on you". Do we suppose that as soon as the clock was a ETA zero that they stopped in their tracks and started circling or was this perhaps sometime after ETA was zero, some number of miles later? Would they continue on the same heading to see if the Island came in to view? Could the 19:12 GMT report have been transmitted when they decided it was time to give up on the flight line having passed up where they thought Howland was some time ago?

There are a number of possibilities. If Earhart misunderstood the LOP approach process then she might have sent this message when they first turned onto the LOP. As an example I have been assuming intercepting the LOP 60 NM north-northwest and, to make it simple, assume they are making a ground speed along the LOP of 120 knots, 2 NM per minute so this would make the call 30 minutes premature.

Or, she might have made the call 30 minutes after the interception which would place then very near Howland. But would she say "MUST be on you" at this point since, when doing the LOP approach, the island could still be another 60 NM ahead? Let's put it in everyday terms. Your buddy gave you directions to his house, "get off the freeway and drive five miles west on route 34." So you get off the freeway and watching you odometer you drive until is says "5.0" miles and you haven't seen your buddy's house. Would you at the exact "5.0" mile point get on your cellphone and call your buddy and say "I must be at your house but I cant's see it?" Probably not. You would probably drive a couple of miles further before making this call because there might have been some inaccuracy in your buddy's directions or in the odometer readout. When you have gone far enough that you are sure that you have missed it you get on the phone.  This is the third place where Earhart may have made that call, when Noonan was sure they had missed the island and this would be 60 NM past the place where they expected to be right over the island so this would be 30 minutes after that point. I'd guess the third choice is the most probable or someplace between two and three, she might have been getting antsy.

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3) If they did give up on finding Howland on the flight path, would they back track (do a 180 turn) to where they originally thought Howland was or would they just begin a search pattern where found themselves after giving up?
They should go back to where they expected the island to be, say 60 NM, but they shouldn't follow back on the LOP since they have already searched that area but should sidestep and parallel the LOP by slightly less than twice the visibility so as to search that area effectively.

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4)  How long do you suppose they sat their circling before taking some action? They searched for a full hour before the final transmission at 20:13 GMT. Would they have been aware of the 10% worst case error in the DR and immediately headed North and South on the 157/337 LOP to determine if they were North or South of Howland?
After flying back the 60 NM (in my example) and absent aquiring additional information, they should start an expanding square search pattern, or a modification of it, and continue it until finding the island or running out of fuel. The moon was available and might have been visible at their altitude (depending on cloud cover) or they could have climbed above the clouds to shoot it and the sun again. The moon was positioned to give them information on whether they were north or south of Howland. The moon also would have allowed them to know how far from Howland they were when intercepting the LOP.
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5) Why choose the 157/337 line anyway? I am not seeing the logic for following this LOP unless their line of approach that was pre-determined ahead of time was 90 degrees out from this line.
They had no choice, it was determined by the location of the sun. The LOP runs at right angles to the azimuth of the sun. When the sun rose, and for an hour afterward, the azimuth of the sun was 067° true which causes the LOP to be 90° greater, 157° and it reciprocal, 337°. For a more complete description of the LOP approach process go to my website here and here.
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Thank you in advance.

gl
« Last Edit: January 09, 2012, 03:07:25 AM by Gary LaPook »
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #187 on: January 09, 2012, 02:54:58 AM »

Quote from Bruce Thomas -

"Amen, Jeff!"
   
Thanks for your kindness and encouragement, Bruce.  Wisdom itself.

Yes, I realize we do seem to re-hash, but the upside as I see it is that we have a number of new and active people here who are trying to get a grasp - that's great news to me.  They also tend to bring new thinking into old ideas - something some of the leadership at TIGHAR has encouraged at times.

As to the navigation aspects of this string, I've done some review and came up with a point or two I'd like some help with - if Gary LaPook can help me on this it would be appreciated.  From "Noonan Navigation Error" on May 29, 2011:

No, they didn't plan to rely solely on the radio to find the island but planned on having two separate redundant methods either one of which, all by itself, was capable of taking them to a safe landing at Howland.

I don't buy your argument that AE could have flown without navigating to within RDF range of Howland, but I accept the idea that Fred did provide a backup system of sorts.

The RDF systems we know about are three: Itasca, Howland Island, and the plane.  All three failed.
--------------------------------------------------------------------------------------

Some more evidence to convince you:

On the flight from Oakland to Hawaii they were able to get radio bearings on stations that were more than 600 NM away.

Pilots ferrying small planes across the Pacific and the Atlantic back in the 1970's, before the advent of LORAN C or GPS, universally did exactly that,  they DRed all the way with only an ADF for terminal guidance, relying on DR to be able to get them within the range of the radio beacon at the destination. (I only know of two exceptions to this, one is Ken Gebhart, who now owns the company CELESTAIRE which sells navigation equipment, and myself, we both used celestial navigation.) (see: http://www.celestaire.com/ ) Of course, in the '70s, radio was much more reliable but the range was still the same, the physics of radio propagation had not changed.

The longest leg on the Pacific crossing is California to Hawaii and is about 2100 NM depending on which airport you leave from which is insignificantly shorter than the leg from Lae to Howland. See:  http://www.fer3.com/arc/m2.aspx?i=108664&y=200906


So it would not have been unreasonable for Earhart, by herself, alone in the airplane, to rely solely on DR and then trust the radio for terminal guidance, to fly the leg from Lae to Howland if she had been content to have no redundancy, no second independent navigation method that was capable, by itself, to get her all the way to Howland. To have this second, redundant, navigation system on board she need Noonan.

In the end, both systems failed, stuff happens. Similarly, sometimes a skydiver's reserve parachute fails too and he gets killed. Even redundant systems cannot guarantee success.

BTW, the Itasca's radio direction finder did not fail. The Itasca's RDF was not capable of taking bearings on the frequencies that Earhart transmitted on. Since it was limited to 270 to 550 kcs  she could have transmitted on 3105 and 6210 kcs until the cows came home and they could not have taken a bearing on her. Itasca informed Earhart of the frequency range of their RDF by radiogram on June 28th and this document is available on the Purdue archive website.

Gary LaPook

Gary, does this mean that in your view AE could have had a reasonable assumption at Lae that if all went well with her radios, etc., FN was good to have but not necessarily vital?

Until recently, I've mostly understood that FN was considered vital to within a short range of Howland (can't quantify how 'short' at moment, but meaning FN would get them 'close') - and I've come think I'm off base in that now. 

I've come to believe that DR to near Howland wouldn't have been out of the question (yes, even for AE), especially if one believed RDF was going to work at the end of things.  That's not an endorsement of how savvy I believe AE was regarding RDF use...
Not especially but only if she was 110% certain that her radio equipment and that of the Coast Guard would be working. But they had had continuous trouble with it, for instance, Noonan complained that it didn't work on the approach to Dakar. The whole flight was planned around have to need a navigator since the realized that radio was not 110% reliable. In the '70s when ferry pilots relied on DR alone to bring them within range of the radio beacon at the destination island, radios were much more reliable than in the '30s. Still, some ferry pilots were never seen or heard from again.
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Now, for one thing, if I am following and recalling my own experience correctly, RDF isn't such a short-range affair (when it works).  Duh, I should have realized that - where I am I'm simply more self-bound by the abundance of stations out of a habit of using those that are much closer in nearly all cases (just gotta get out more).  Over the open ocean my 'habit' would give way to the one station I needed... and well over the horizon's no big deal for reception / bearing.  Might squiggle around in the sky a bit, but eventually would find the station.  In fact, DR should keep me reasonably close to track until I could pick up the station a few hundred miles out, then it's a matter of correcting a relatively minor error and tracking in (again, if my set and the station both are working well).

Then, if DR and RDF failed AE, FN was always there, whether in a parallel effort or as a back-up (won't argue which), to ensure a Howland arrival could come together. 

I apologize if I'm just re-hashing what I believe you clearly stated above, but that was a while back and I am just trying to be thorough.  You guys who did fly the oceans have far more experience than I do with DR and RDF terminal nav, but I 'get' the point and appreciate your thoughts.

Is my take away on this correct?

LTM - and thanks in advance,


This type of equipment is good for a very long distance mainly determined by the power of the transmitting station. For enroute navigation, airways, like "highways in the sky" were created with radio transmitters placed on the ground at each end of each leg of the airway. The signals have to be strong enough so that you can receive them at the halfway point of each airway leg. You track outbound from one station until halfway to the next station then start following the signal to the second station. As an example, a route I flew many times
was "Amber 17" from Bimini, Bahamas to Puerto Rico. You take off from Miami or Ft. Lauderdale and tune in the radio station on Bimini which transmits on 396 kcs with a morse code identification of "ZBB." You use the radio direction finder to head for Bimini which is 55 NM from Ft. Lauderdale. After passing over Bimini you turn to a heading of 121º magnetic and track outbound until halfway to the next radio station located on the island of Grand Turk at the very southeast end of the Bahamas chain. Grand Turk transmits on a frequency of 232 kcs with
the ident of "GT." After passing GT the next station is located on the north shore of Puerto Rico about 60 miles west of San Juan transmitting on the frequency of 391 kcs, ident "DDP." Now here is the important part, the leg from ZBB to GT is 516 NM (593 miles). This means that you must be able to receive the signal at least 258 NM from each station. It is reasonable to believe that had AE's radio direction finder been working she would have been able to hear Itasca at a similar or longer distance because GT only put out 400 watts and the Itasca put out 500 watts. This is born out by the fact that Itasca heard AE's much less powerful transmitter several hundred NM out. Amber 6 from Galveston to Cozumel is a leg of 687 NM so you had to be able hear each beacon for almost 350 NM.

Commercial stations can be heard much farther than this. I remember many times flying from Miami to Chicago, in the middle of the night, I would tune in WLS, 890 khz 50,000 watts and would follow it all the way from Miami to
Chicago a distance of a little over 1000 NM.


Since the leg from Lae to Howland is 2222 NM and the common estimate of DR accuracy is 10% of the distance flown then one could expect to fly the distance from Lae to Howland solely by dead reckoning and still be confident of coming within in 222 NM of Itasca and so be close enough to pick up the radio signal and track inbound to Howland. So if AE was willing to rely only on radio she didn't need Fred. But obviously they wouldn't just rely on radio.

It is hard for young people today who have grown up with cell phones, the internet, TV, satellite dishes and IPODs to have any gut feeling for the unreliability of radio equipment in the 1930s. Modern equipment and systems are so reliable people don't even think about it anymore. But in the '30s, comparing the reliability and trust in complicated pieces of electronic equipment with resistors, capacitors, and tubes that burned out without warning in your own equipment and in the transmitting equipment that was not under your control, with the
proven reliability of a simple sextant, a book of tables and a clock (or two clocks for redundancy) and celestial won hands down. That was why AE hauled Fred all the way around the world.

gl
« Last Edit: January 10, 2012, 02:07:53 AM by Gary LaPook »
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Heath Smith

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Re: The flight plan, magnetic course, headwinds.
« Reply #188 on: January 09, 2012, 04:24:32 AM »


Quote
Since the leg from Lae to Howland is 2222 NM and the common estimate of DR accuracy is 10% of the distance flown then one could expect to fly the distance from Lae to Howland solely by dead reckoning and still be confident of coming within in 222 NM of Itasca and so be close enough to pick up the radio signal and track inbound to Howland. So if AE was willing to rely only on radio she didn't need Fred. But obviously they wouldn't just rely on radio.

Gary,

Thank you for the detailed information in the previous post. I have yet to read over both of your links but will check it out after work. I have a simple question about the maximum error of 10% of the distance traveled. In your above example 10% DR results in 222NM. Is this the 'total error' meaning you could be 5% North or South of your target or does this mean you could be 10% too far South or 10% too far North? For example, if you were about to start searching, are the end points to the error window 111NM to the North and 111NM to the South or is it 222NM to the North and 222NM miles to the South?

Assuming that it is 111NM North and 111NM South, and you started searching in the Northerly direction, would you travel the entire 111NM or stop short of the visibility range and turn around to go South? I am guessing on the trip South you would make the offset short of 2 times the visibility range. Would the choice of choosing an Easterly offset or a Westerly offset be arbitrary on your first pass?

Thank you in advance.
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #189 on: January 09, 2012, 06:45:21 AM »

According to Long, they landed at Lae at 3:05 p.m. on the 29th ...

... not much time to do any sightseeing that day since sunset was less than three hours later and they had to put the plane to bed first, check into the hotel etc., and she reported some sightseeing in the first dispatch.

I agree it is a narrow window of opportunity for all of the events portrayed in the newspaper article.

Quote
I looked at your table of transmissions. Looking at the disputed dispatch it could not have been sent on the 29th. Read the story as reprinted in Last Flight and you will find her saying "We stayed at a hotel...", past tense, not a present tense, "We stay at a hotel..." or "We are staying at a hotel..." It is clear that this was sent after spending a night in the hotel in Lae so it must be June 30th, not June 29th.

OK.  I've removed the quibble.  So you do have a copy of the newspaper article? 

Quote
I believe the credit arrangement allowed her to send both of the dispatches from Lae.

OK.  That's conceivable.

Quote
By Nukulau in the Fijis, I take it you are talking about a cable landing in Suva.

No.  By "Nukulau" I meant "Rabaul."  Don't ask me how I arrived at that inversion.   :-\

Quote
There were no telephone cables to Suva either from the U.S or from New Guinea in 1937, see chart of cables.

You're overworking that chart, which hasn't been properly introduced to us.

It's a secondary source.

The caption says this, with emphasis added:

"Fig. 119.  Cable and wireless communications.  This map shows cables and the main outline of wireless communication in the Pacific area in 1939.  Based on various sources."

That means that the map is not an exhaustive list of "wireless communication in the Pacific."  It can't be used to exclude Lae, nor can it tell us when someone in Lae could make a phone call to the U.S. by means of a landline and a patch to a wireless transmitter.

Moreover, it's got a lot of small islands listed.
  • Tarawa
  • Beru
  • Funfuti
  • Nauru
  • Moumea
Whatever it is charting, it doesn't sound as though it was the huge, prohibitively expensive operation you outlined earlier.

Quote
There were no telephone lines out of Lae to anywhere, which is why it was a big deal when local radiotelephone links were established in 1939.

Source (secondary or otherwise)?
LTM,

           Marty
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Gary LaPook

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Re: The flight plan, magnetic course, headwinds.
« Reply #190 on: January 09, 2012, 09:38:24 AM »

According to Long, they landed at Lae at 3:05 p.m. on the 29th ...

... not much time to do any sightseeing that day since sunset was less than three hours later and they had to put the plane to bed first, check into the hotel etc., and she reported some sightseeing in the first dispatch.

I agree it is a narrow window of opportunity for all of the events portrayed in the newspaper article.

Quote
I looked at your table of transmissions. Looking at the disputed dispatch it could not have been sent on the 29th. Read the story as reprinted in Last Flight and you will find her saying "We stayed at a hotel...", past tense, not a present tense, "We stay at a hotel..." or "We are staying at a hotel..." It is clear that this was sent after spending a night in the hotel in Lae so it must be June 30th, not June 29th.

OK.  I've removed the quibble.  So you do have a copy of the newspaper article? 
No, I do not have a copy of the newspaper, I thought that Ric did. I've been working from the last chapter of Last Flight which is a reprint of those two stories. So Ric is working with a secondary source which brings up the possibility of another source for the erroneous byline. If the first person writing a book about Earhart got this wrong, wrote "telephone" instead on "telegraph," then everyone copied from his book as in the other examples I gave.
Quote



Quote
I believe the credit arrangement allowed her to send both of the dispatches from Lae.

OK.  That's conceivable.

Quote
By Nukulau in the Fijis, I take it you are talking about a cable landing in Suva.

No.  By "Nukulau" I meant "Rabaul."  Don't ask me how I arrived at that inversion.   :-\

Quote
There were no telephone cables to Suva either from the U.S or from New Guinea in 1937, see chart of cables.

You're overworking that chart, which hasn't been properly introduced to us.

It's a secondary source.

The caption says this, with emphasis added:

"Fig. 119.  Cable and wireless communications.  This map shows cables and the main outline of wireless communication in the Pacific area in 1939.  Based on various sources."

That means that the map is not an exhaustive list of "wireless communication in the Pacific."  It can't be used to exclude Lae, nor can it tell us when someone in Lae could make a phone call to the U.S. by means of a landline and a patch to a wireless transmitter.

Moreover, it's got a lot of small islands listed.
  • Tarawa
  • Beru
  • Funfuti
  • Nauru
  • Moumea
Whatever it is charting, it doesn't sound as though it was the huge, prohibitively expensive operation you outlined earlier.
These were short range radio telegraph links, not the trans-ocean link necessary to reach the U.S. 6,500 SM away.
Remember, "wireless" is short for "wireless telegraphy" which means CW using Morse code. Of course the chart does not exclude Lae from having wireless communications since we know that it did, Mr. Balfour pounding away on his telegraph key. It does show that no telegraph cable went to New Guinea. See the details of the short range radio links necessary to get radiograms to and from Lae. Information about two "point-to-point" stations showing the massive antenna farms needed is here and here.

There were no telephone lines out of Lae to anywhere, which is why it was a big deal when local radiotelephone links were established in 1939.
Quote

Source (secondary or otherwise)?

We are confronted with the difficulty of a proving a negative, that they did NOT have telephone service in Lae in 1937. We are not going to find a series of articles in the "Lae Daily Journal" (if there was such a paper) stating:

"Byline Lae NG, January 1, 1920, No telephone service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1921, No telephone service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1922, No telephone  service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1923, No telephone service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1924, No telephone service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1925, No telephone service in Lae to the outside world available yet."

...

"Byline Lae NG, January 1, 1937, No telephone service in Lae to the outside world available yet."

"Byline Lae NG, January 1, 1938, No telephone service in Lae to the outside world available yet."

We have to make reasonable inferences from what we do have such as the announcement of local service to four towns in 1939. A reasonable inference is that these are the first four towns, including Lae, to be linked by radiotelephone, that no such service existed to anywhere prior to this. An unreasonable inference from this would be that Lae had communications with every other town on earth and these were the last four to be reached. Additional support for the logic that there was no telephone service was the lack of any newspaper stories during the heat of the search headlined:

"EXCLUSIVE! PHONE CALL TO LAE REVEALS......."

Since the newspapers, especially the Herald Tribune, would be expected to make such contact, if it were available, the lack of it lends support to the inference that it was not available.

Even in murder trials with the burden of proof being "beyond a reasonable doubt" jurors are allowed to decide that something is a fact, that was not proved by direct evidence, by reasonable inference from the facts that were proved by direct evidence.

John is found shot dead and nobody saw the actual shooting. Bill is on trial for the crime. Charles testifies " I came into the room and saw Bill standing over John with a smoking gun in his hand." Bill is convicted because the jury made the reasonable inference, from the proven facts, that Bill shot John. I have attached the standard California jury instruction given in all jury trials in California addressing this issue.

gl
« Last Edit: January 09, 2012, 10:06:19 PM by Gary LaPook »
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Harry Howe, Jr.

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Re: The flight plan, magnetic course, headwinds.
« Reply #191 on: January 09, 2012, 02:02:27 PM »


Anyone wondering why FN was there need pnly read The Brine Letter in which Russell Brine gives us his read on how good AE was at navigating.  She was inept at best, that's why FN was there.
No Worries Mates
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Harry Howe, Jr.

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Re: The flight plan, magnetic course, headwinds.
« Reply #192 on: January 09, 2012, 06:04:46 PM »


Anyome wonder why there weren't any radio messages from AE/FN for more than 4 hours after takeoff?  2:18 PM Lae Time  04:18 GCT

Perhaps AE had her hands full taking off, finding her course, climbing to altitude, taking care of Fred, etc
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #193 on: January 09, 2012, 07:45:18 PM »

These were short range radio telegraph links, not the trans-ocean link necessary to reach the U.S. 6,500 SM away.
Remember, "wireless" is short for "wireless telegraphy" which means CW using Morse code. Of course the chart does not exclude Lae from having wireless communications since we know that it did, Mr. Balfour pounding away on his telegraph key. It does show that no telegraph cable went to New Guinea. See the details of the short range radio links necessary to get radiograms to and from Lae.

Quote
There were no telephone lines out of Lae to anywhere, which is why it was a big deal when local radiotelephone links were established in 1939.

We are confronted with the difficulty of a proving a negative, that they did NOT have telephone service in Lae in 1937. ...

We have to make reasonable inferences from what we do have such as the announcement of local service to four towns in 1939. A reasonable inference is that these are the first four towns, including Lae, to be linked by radiotelephone, that no such service existed to anywhere prior to this. An unreasonable inference from this would be that Lae had communications with every other town on earth and these were the last four to be reached. Additional support for the logic that there was no telephone service was the lack of any newspaper stories during the heat of the search headlined:

"EXCLUSIVE! PHONE CALL TO LAE REVEALS......."

Since the newspapers, especially the Herald Tribune, would be expected to make such contact, if it were available, the lack of it lends support to the inference that it was not available.

Yes, I understand the difficulties of proving a negative.

Yes, I feel the force of your argument.

Since it supports my view that the Gore anecdote is a fabrication (conscious or unconscious), I'll let it rest for now.

There may be something already in the Purdue files that are not accessible by internet.  I don't know whether those "hidden" files are off-limits to folks on site.  If I ever get near Purdue with a day or two in hand, I may try to visit the library and see if I can find out the nature of the "hidden" material.

I assume that the stuff we can see was collected by Putnam for Last Flight.  If it's in the book, it seems to me that it ought to be in the Purdue collection somewhere.  It is, of course, equally conceivable that the original just got lost in the shuffle.

Quote
Even in murder trials with the burden of proof being "beyond a reasonable doubt" jurors are allowed to decide that something is a fact, that was not proved by direct evidence, by reasonable inference from the facts that were proved by direct evidence.

Understood.

Meanwhile, FWIW, I've accepted your interpretation that the 29-06 telegram from Hill to Putnam was sent at sent at 11:32 PM.  That seems a reasonable interpretation of "FA 11 32" and fits with the boilerplate on the forms that says the time that the message was received should be in the first line. 
LTM,

           Marty
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Martin X. Moleski, SJ

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Re: The flight plan, magnetic course, headwinds.
« Reply #194 on: January 09, 2012, 07:50:20 PM »

No, I do not have a copy of the newspaper, I thought that Ric did. I've been working from the last chapter of Last Flight which is a reprint of those two stories. So Ric is working with a secondary source which brings up the possibility of another source for the erroneous byline. If the first person writing a book about Earhart got this wrong, wrote "telephone" instead on "telegraph," then everyone copied from his book as in the other examples I gave.

So far as I can tell, back issues of the Tribune are not available online.  The Tribune does not seem to be in the Google Newspaper Archive (which is dead--bummer!).

I don't know whether Ric has a copy.  We may find out eventually.
LTM,

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