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Author Topic: Earhart's first contact.  (Read 6482 times)

Heath Smith

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Earhart's first contact.
« on: December 11, 2011, 06:37:55 PM »


Looking over the Itasca log on the Purdue site it seems that the coast guard had assumed Earhart had reported two estimates of the distance to her target, supposedly one at 200 miles out and one at 100 miles out (see page049 at the archive where they clearly state "At 100 miles out" she made a report). I believe this was discussed at some point in time here on the forum but I could not locate the thread.

From the Itasca log:

0614 Wants bearing on 3105 kcs/on hour/will whistle on mic.

0615 About two hundred miles out//appx//whistling//NW. (Volume S-3.)

0642 KHAQQ came on air with fairly clear signals calling Itasca (voice).

0645 (KHAQQ REQUESTED) Please take a bearing on us and report in half hour I will make noise in microphone - about 100 miles out (Earhard signal strength 4 but on air so briefly bearings impossible.)

Is it possible that perhaps when she made the broadcast at 0645, she was not saying "I am 100 miles out" but rather "I will make noise in microphone at about 100 miles out"? It does makes sense that she promised to report it at 0645 which she did and also that she wanted to let them know when she would be at 100 miles out (in the future perhaps).

It is clear that at this time, she was reporting in a 15 and 45 just as she said she would. It was not until 7:58 that this trend was broken when she reported "we are circling". Specifically reports at 0615 , 0645. She should have transmitted at 7:15 but apparently did not or it was not received. Her next report was at 0742, sticking close to her promised half hour reports.

If you believe the coast guard's assumption, then she traversed 100 miles in 30 minutes, the Electra's air speed was 200 miles per hour. While possible on a decent, would substantially increasing the speed on a the decent without a target in sight be warranted?

As an alternative, assume that she continued along at the same speed. At 0615 she was 200 miles out. At 0742 she said "we must be on top of you". That is about 87 minutes between reports. If we assume that she traveled 200 miles in that time,  that suggests an airspeed of about 138 mph, very close to the estimates that I have read elsewhere in the forum. Working that backward, she would have been at 130.5 miles out when the scheduled 0645 report was received.  If true, this might be useful information to compute remaining fuel assuming that she was being conservative on her approach.

If we assumed that they were moving at 138 mph, at the report at 0615 was accurate, traveling at 138 mph would have require about 44 minutes to travel 100 miles. She should have reported in right around 0700 if this was true. In fact nothing was heard (from what I can see) until 0742. Perhaps the 0614 report suggested that they would make this report at 0700 when it states "/on hour/", not "in an hour" or "every hour". This "on hour" seems a bit out of place give the half hour reports. The 0614 and 0645 seem to promise "noise on the mic" which I cannot see in this log after the 0615 report was she was whistling at 200 miles out. It suggest that two reports were perhaps meant to be sent at 0700 (for 100 miles out) and 0715 (scheduled report) but neither were sent or perhaps neither were received.

On a side note, At 0742, witnesses claim to have heard only 1/2 hour of fuel left. This was added to the log after the fact. This is dubious because she reports in at 0758 and suggests the next report in another half hour if they do not want to talk right then. This does not sound like panic. Almost a full hour after the 0742 report, the infamous report at 0844 "We are running on the line 157-337" is heard. So much for the 30 minutes of fuel left. Even if you believe the supposed reports, and Earhart did say that she had 30 minutes of fuel, that estimate was at least 100% off the mark.

Another interesting note of the only change in signal strengths reported other than 5 after 0742.

At 0615 it says (Volume S-3)
(question, is this a signal strength 3?)

At 0645, signal strength 4.

At 0742 signal strength 5.

I only mention this because of the region in the log of interest. I am not sure if that offers anything substantive on the signal strength but at least is something to start a model with.
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Ric Gillespie

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Re: Earhart's first contact.
« Reply #1 on: December 12, 2011, 09:55:34 AM »

I share your doubts about the "100 miles out" notation but I had never run the numbers as you did.  Nice work.
BTW, what you were looking at on the Purdue website is not the Itasca radio log.  It's Thompson's "Radio Transcripts Earhart Flight."  Not at all the same thing.

When trying to reconstruct what happened it's important to use the raw log that Chief Radioman Leo Bellarts salvaged.  The strike-overs and erasures speak volumes.  See Log Jam.  For example, a close examination of the original log makes it clear that the word "circling" was originally typed as "drifting."  Earhart probably actually said "listening."  See Things Not Said.  In that research bulletin I wrote:

"The radio log shows that Amelia probably never said “about one hundred miles out” at all. It is clear from the platen mis-alignment that the phrase was later added to the 0646 entry in which Earhart says she “will make a noise in the microphone” upon which she hopes Itasca will take a bearing. It is also clear from an earlier entry that this operator uses a dash to separate his own comments from the text of the message. With the added knowledge that it was part of the operator’s duty to judge distance based on the strength of reception, it becomes apparent that the “one hundred miles out” estimate is the operator’s, not Amelia’s."

You say - "Another interesting note of the only change in signal strengths reported other than 5 after 0742."

Others have drawn very specific conclusions about how far way the airplane was at those times based on the signal strengths Thompson included in his report, but those estimates do not appear in the original log.  They are after-the-fact recollections.
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Heath Smith

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Re: Earhart's first contact.
« Reply #2 on: December 12, 2011, 03:10:25 PM »


Ric,

Thanks for the links. I will need to check out the raw log that you mentioned.

I found this document that appears to be a telegram from a Miami Radio Station to the S.F Division of the Coast Guard stating that Earhart planned to spend most of her time taking radio bearings.

If this device was not that useful, or she did not know how to use it, why would she dedicate so much time to the task and limiting voice traffic?

If the SF Office knew this was the cause, why would they not dedicate a transmitter specifically for this purpose or at least try to clarify this with Earhart before she departed Lae?
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Ric Gillespie

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Re: Earhart's first contact.
« Reply #3 on: December 12, 2011, 04:46:34 PM »

I found this document that appears to be a telegram from a Miami Radio Station to the S.F Division of the Coast Guard stating that Earhart planned to spend most of her time taking radio bearings.

The telegram is from the Coast Guard Radio Station in Miami that handled aviation traffic to Coast guard San Francisco Division that was trying to coordinate radio procedures for the Lae/Howland flight - and not having much luck.  There were zilch communications between the Earhart/Putnam organization and the Coast Guard prior to and after the departure from Miami on June 1 until the flight got to Java three weeks later.  Drove the CG nuts.

If this device was not that useful, or she did not know how to use it, why would she dedicate so much time to the task and limiting voice traffic?

I don't know why she said what she did.  It may be that she really did intend to use her receiver almost exclusively for radio bearings, but there's no evidence that she ever actually did.  It's also possible that she said that just to discourage people from calling her on the radio because she didn't want to be bothered.  It was not unusual for AE to lie to the press.

If the SF Office knew this was the cause, why would they not dedicate a transmitter specifically for this purpose or at least try to clarify this with Earhart before she departed Lae?

If you're really curious about what transpired between Earhart, Putnam and the CG in trying to sort out radio communications and procedure for the Lae/Howland flight it's all in Finding Amelia.
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