Forum artHighlights From the Forum

November 7 through 13, 1999


Subject: The Luke Field Patch
Date: 11/7/99
From: Vern Klein

I think I have little choice but to try to see where this will lead.

>From Ric
>
>Well, as Vern says, "first there is anecdote" and this one is a doozy. The
>first thing I can think of to do is check the official USAAC report which
>meticulously describes the events in Hawaii from the time the aircraft
>arrived from Oakland until it was wrecked on takeoff from Luke Field. But
>Jack's story, if I understand it right, does not claim that the patch is a
>repair done before the crash but afterward. I don't think we have any
>information about any repairs done before the airplane was shipped back to
>California. It's sort of hard to think why they would do that.

Yes, it is certainly my impression that this patch was a repair done after the crash. I guess that means the USAAC report would be no help. Hmmm.. a patch applied BEFORE the crash? I don't think we know of any reason that would have been needed. The Lockheed Repair Order suggests that a pre-crash patch, if any, did not survive... unless the story relates to a patch in some totally different location on the plane.

I'm not familiar with what may be available to help track down people who were at the Ford Island Depot, Luke Field in 1937... or any sort of documentation relative to repair activities there. I would appreciate any suggestions, especially anything I might do via the Internet. Easy things first!

A question... There are the Lockheed Repair Orders signed off as completed. How certain can we be about where the skin repair work was done? Can we admit the possibility that, for reasons unknown, the skin repair was already completed when the plane arrived back in California? I can't imagine that the other work was done anywhere except at Lockheed.

LTM (who was always a sucker for a strange tale!)
Vern


From Ric

The skin work pretty much has to be the last thing done. First you take off the damaged skin, then you repair the underlying structure (stringers, bulkheads, etc.), then you rivet on the new skin. The only photos I've seen of the airplane under repair in Burbank show the skin repair already pretty much complete except for one section under the center section. I just can't make a post-crash skin repair in Hawaii make any sense but that could just be a limitation of my imagination.

One thing about the story that does track with the facts is that the markings on the aluminum do indicate that the stock from which 2-2-V-1 was made was not from a regular production run but was excess stock that may well have been used for field repairs. The question, of course, is what field and what repairs?

Perhaps some forum members have advice on how to find people who were there in '37.

LTM,
Ric


Subject: Thoughts on the Patch
Date: 11/7/99
From: Mike Everette

Some thoughts on the Patch Issue:

During the modifications at Lockheed, the configuration of the dorsal Vee antenna was changed. The apex of the Vee was moved forward on the top of the fuselage. Also, the location of the insulator which passes the antenna feedline through the fuselage to the radio transmitter was changed.

Neither of these locations are on the belly of the aircraft.

Maybe these locations on the skin should be checked closely.

Is there any possibility that this patch could be associated with either of these modifications?

Is it also possible that the patch could have been applied at the time the trailing wire antenna was removed, to cover the hole left by the feed-through mechanism? This one would be on the belly.

Would an entire piece of skin be replaced, or a simple patch applied over such an opening? (I'm a communications person, not an A/P; so I don't know.)

73
Mike E. the Radio Historian


From Ric

Good thoughts.

>The apex of the Vee was moved forward on the top of
>the fuselage. Also, the location of the insulator which passes the antenna
>feedline through the fuselage to the radio transmitter was changed.

My first reaction is that these changes should not require a patch as big as 2-2-V-1, but it's certainly worth a close look at the photos. I do know that the skin thickness on the top of the cabin was .032, the same thickness as 2-2-V-1.

>Is it also possible that the patch could have been applied at the time the
>trailing wire antenna was removed, to cover the hole left by the
>feed-through mechanism? This one would be on the belly.

As I recall, that whole area was wiped out in the wreck and replaced in Burbank, but I'll double check.

>Would an entire piece of skin be replaced, or a simple patch applied over
>such an opening?

I'm not an A&P either. The repair orders call for some entire skins to be replaced but for other areas to simply be "repaired".

LTM,
Ric


Subject: Unusable fuel?
Date 11/7/99
From: Herman de Wulf

All these mathematics are interesting, including fuel consumption and venting. But what about USABLE FUEL in a Lockheed 10E ? Any aircraft can be filled to capacity with fuel but we all know you'll never get the last drop out of it. At least, that's what we've been taught in flying school. I learned to calculate fuel consumption and take into account the fact that there WILL remain x gallons in the tanks when the engine runs out of fuel. So all the calculations some of us make on how long the engines exactly worked and when they went dead so far is very theoritical. Does anyone know what the amount of USABLE FUEL was in a Lockheed 10E ?

LTM
Herman (who ran a tank dry once and was lucky enough to have another with some 100LL left in it)


From Ric

The schematic of Earhart's fuel system shows that the aircraft was equipped with a "stripping valve" and a "strip wobble pump." It is my understsanding that these devices are designed to minimize the amount of unusable fuel. I do not know how efficient they were.


Subject: More Thoughts on the Patch
Date: 11/7/99
From: Ric Gillespie

Mike Everette wondered if the moving of the dorsal mast and the antenna lead-in following the Luke Field accident may have occasioned the installation of a patch which might account for our Artifact 2-2-V-1. (2-2-V-1 is the section of airplane skin we found on Niku in 1991 and have been trying - unsuccessfully so far - to place on some airplane, any airplane. It has the look and feel and flavor of a Lockheed 10 but the rivet pattern doesn't match any standard part of the airplane. For a while we had a really strong hypothesis going that it was a patch installed on the belly during the repairs which fllowed the Luke Field crash, but we finally found photos that enabled to see the area in question with sufficient detail to see the rivet pattern. No joy. Hypothesis disproved. Years of work down the toilet.)

I replied to Mike:

"My first reaction is that these changes should not require a patch as big as 2-2-V-1, but it's certainly worth a close look at the photos. I do know that the skin thickness on the top of the cabin was .032, the same thickness as 2-2-V-1."

I have looked at the photos.

Pictures showing the top of the fuselage are few and far between. None that we have are of sufficient resolution to see rivet patterns. Bummer. I still think that the simple moving of a mast would not require a big patch in the old location. However, in considering the possibility, it occurred to me that this was not the first change to be made to that part of the airplane. Back in the fall of 1936 the airplane was equipped with the Hooven/Bendix Radio compass which featured a large faired dome over a DF loop. The original mast was installed just forward of the dome. The Hooven/Bendix dome was removed in early March 1937 and replaced with the now-familiar open loop over the cockpit. That removal had to leave several holes to be patched. Moving the mast forward after the Luke Field wreck meant yet another small patch in that same skin. I can see somebody saying, "This is a mess. Let's just put in one big patch instead of having all these weight and drag producing little patches."

Just a hypothesis at this point, of course, but worth looking into. First question - what does the seam down the center of the top of the fuselage look like?" None of the photos I have of various Model 10s show that particular detail. If it's a simple overlap with #5 size rivets, the hypothesis passes the first test. Anyone want to check this feature out on their neighborhood Electra?

LTM,
Ric


Subject: Post-Disappearance Radio Messages
Date: 11/8/99
From: Vern Klein

Some further thoughts regarding hams (amateur radio operators) and possible hoax transmissions. As has been stated before, in 1937, hams had a lot of respect for (fear of) the FCC. They had a lot to lose. Illegal operation of a transmitter could result in loss of a license, confiscation of equipment, a substantial fine and even jail time. A hoax transmission on a frequency such as 3105 kc would be kind of thing that could get you some jail time.

Perhaps more significantly, in 1937 very few hams were technically able to transmit on 3105 kc -- or any other frequency outside the assigned ham bands. Virtually all ham transmitters were crystal controlled. It was the only way to be sure you were within a ham band. A ham would have just a few crystals on hand that he could plug in for a particular frequency in the band. Even then, they were nervous about operating close to a band edge. There were probably a few hams with tunable transmitters and frequency monitoring equipment to ge sure where they were. You needed something better than the tuning dial of your receiver for that. I think very few were so equipped in 1937.

Much the same could be said for non-american hams. There would be no reason to have a crystal to get you on 3105 kc. No other ham would hear you there and that particular frequency would have got you in big trouble whatever government might be monitoring the frequency and DF on you. They did that sort of thing in 1937. I don't think they even try now. It's become more than they can cope with.

In essence, it would have been difficult for a ham operator to have got set up to transmit on 3105 kc in the few days following the disappearance of the Earhart flight. If there were hoax transmissions on 3105 kc, they probably originated with people, other than hams, who had access to a transmitter that could be switched to 3105 kc -- or 6210 kc if such transmissions were heard. I don't remember whether anything was reported other than on 3105 kc.


Subject: Re: Lockheed Model 10 Production List
Date: 11/8/99
From: Patrick Gaston

Well, if the ground is old and thoroughly plowed, perhaps you could enlighten us ... which eight Electra 10E's (aside from Earhart's) were unaccounted for as of 1978? And have there been any subsequent developments which would allow the list to be narrowed further?

LTM (whose plow needs sharpening anyway)
Pat Gaston


From Ric

The logic goes like this:

  1. The airplane in the Wreck Photo appears to be a Lockheed 10.
  2. If it is a Lockheed 10 it is a big-engined Lockheed 10 (based on the ratio of prop length to cowling diameter).
  3. "Big-engined" Lockheed 10s featured the P&W R1340 and came in two flavors - the Model 10C which had the old 450 hp version of the 1340, and the Model 10E which had the new 550 hp version.
  4. Ergo, if the airplane in the Wreck Photo is a Lockheed 10 it is a 10C, a 10E, (or a 10A or 10B that was modified with the bigger engine).

There were eight Model 10Cs built. The fates of five are known. The unknowns are:

c/n 1004 NC14257 last known owner: PAA Supply, New York City
c/n 1009 NM-15 last known owner: Nacionla Cubana
c/n 1019 N2628 last known owner: unnamed individual in Alamo, TX
(this airplane was converted to 10E configuration)

There were fifteen Model 10Es built. The fates of eight are known. The seven unknowns are:

c/n 1054 NC14994 last known owner: Reeve Aleutian Airways, Alaska
c/n 1055 NR16020 last known owner: Amelia Earhart
c/n 1065 N-124 last known owner: Amtorg, USSR
c/n 1115 M.M. 1 last known owner: Argentine Navy
c/n 1117 NC18139 last known owner: N. Consol. Air (?)
c/n 1125 163 last known owner: Posta Aera (?)
c/n 1134 XH-TAR last known owner: TACA, Mexico

The fates of all of the conversions are known. For example, c/n 1015 was a 10A converted to 10E configuration and is now owned by Linda Finch.

Therefore, if the airplane in the Wreck Photo is a Lockheed 10 it must be one of the 10 airplanes listed above OR it could be one of the accounted-for airplanes that was lost in an accident. Of those the most likely candidate seems to be c/n 1133, XH-TAR, a 10E operated by TACA which crashed at Yoro, Honduras on October 17, 1946. Could the Wreck Photo be an old newspaper photo of that accident? It may have been covered in Mexican papers. It's something that may actually be researchable. Volunteers?

LTM,
Ric


Subject: The Luke Field Patch
Date: 11/8/99
From: Bill

> From Ric
>
> And if you're successful in finding people who are still alive, unless they
> have written records of the event, all you have is more anecdote.

I've got a procedural question. How does a data point get classified on the spectrum from hard facts to anecdote?

What say this investigation turned up a guy who said something like "We started to patch up the Electra, then decided it was too badly damaged. Me and Bob put a patch on the belly at such-and-so a location before we gave it up."

With no documentation, I can see that this wouldn't be accepted as hard fact (the guy could be remembering another plane, for example) but how would it fit?

- Bill


From Ric

In the strictest sense, there is no such thing as "hard fact" in historical investigation. It's the great paradox of historiography that although we must try our best to get to the truth we can never be absolutely sure that we're there. Sort of like trying to reach the wall by decreasing your distance by half at each step. You'll never really get there but you can get awfully close.

Historical evidence falls into three broad categories:

- documentary
- artifactual
- anecdotal

"Documentary" includes information that was written at a time close to the event in question when memories were supposedly still fresh. It also includes photographs. Documentary evidence is, of course, not infallible and the credibility of any given source depends on a lot of factors.

"Artifactual" evidence is probably the best providing that the identification of the artifact is really solid. It's in the interpretation of artifacts that things get sticky.

"Anecdotal" is the least reliable because the human memory is so fallible. There is always a temptation to judge some stories as more credible than others based upon the character or perceived motivations of the witness, but without corroborating documentary or artifactual evidence a good story is still just a good story. The real value of anecdote is that it can lead to the discovery of more reliable evidence.

So, to answer your specific question, if we had a roomful of veterans from the Luke Field Depot who were willing to swear on a stack of Bibles that artifact 2-2-V-1 is the patch they put on NR16020 it wouldn't prove a thing. But if one of them said, "And I made a sketch of it in my work log at the time and here it is right here dated March 23, 1937." then we'd have something.

LTM,
Ric


Subject: That damned patch!
Date: 11/9/99
From: Vern Klein

>From Ric
>... For a while we had
>a really strong hypothesis going that it was a patch installed on the belly
>during the repairs which followed the Luke Field crash, but we finally found
>photos that enabled to see the area in question with sufficient detail to see
>the rivet pattern. No joy. Hypothesis disproved. Years of work down the
>toilet.)

I must have missed something. I take it that you have photos that definitely show that those two extra rows of rivets were NOT in the patch applied to the belly of the plane by Lockheed.

So, I'm left to ponder what patch the guy was talking about that he said was put on the plane at Luke Field. Reading the books again, it looks like the plane was in Hawaii from sometime March 17th until the morning of March 20th. I suppose that was long enough for some minor work to have been done on the plane. What the heck could have happened after leaving Burbank that would have caused a patching job to be done in Hawaii? The books say they did tinker with a few things such as, "lubricating nearly dry propeller bearings." I presume this to relate to the mechanism associated with the variable pitch propellers.

Maybe that USAAC report does contain something. If there's anything at all here, it must be BEFORE the ground loop incident.


From Ric

Check out "Back to Square One for 2-2-V-1".

There's no mention in the USAAC report of any skin work being done. I suspect that what we're dealing with here is yet another example of how memories can play tricks on people.


Subject: Lockheed's Way !!
Date: 11/9/99
From: Dennis McGee

All of this talk of patching the 10E at Luke Field and leaving the repair work undocumented just doesn't track.

Even if the Army had patched the 10E what would be the chances of Lockheed allowing that patch to remain on the aircraft? The plane has THEIR name on it and it is now at THEIR repair facility. How does Lockheed know if all of the damage to the aircraft has been found, and how confident would they be in letting the Army's work stand, without even a cursory inspection?

My guess is that Lockheed's people had thoughts along this line (a tactic borrowed from Edmund Morris, author of Dutch) : "This is a high profile flight by a very high profile aviator using an airplane with OUR name on it. If the plane breaks and the flight fails and/or people die because of something we did/did not do, our reputation is heading south. Let's be real thorough here, go over that plane with a fine tooth comb and use our standards/expertise/engineering to make sure the plane is absolutely perfect and totally airworthy when we give it back."

Lockheed -- and AE/FN! -- could ill-afford a sloppy, undocumented, not-to-spec, jury-rigged repair job that could endanger the flight and its crew. My money --until proven otherwise -- is on a conservative approach: even if the Army had patched the plane [unproven] Lockheed would tear it out [also unproven] and do it their way [proven].

LTM, who avoids "kicking tin" at all costs
Dennis O. McGee #0149CE


From Ric

Motivations are speculative but what is not open to speculation is that the airplane had to pass Bureau of Air Commerce inspection when the repairs were completed. There is a tendency today to think of aviation in 1937 as being primitive, freewheeling, and unregulated. Nothing could be further from the truth. One of the modifications performed on the airplane while it was being repaired was to beef up the landing gear attach points where they met the Main Beam (somewhat analogous to a main spar). This involved the approval of four new engineering drawings and lots of paperwork. The originals of those drawings are now in a special collection at the National Air & Space Museum Library (we have copies).

Several people have provided anecdotal accounts of how impatient AE was for the repairs to be completed. She apparently spent a lot of time at the shop pestering management and cutting red tape. The airplane was signed off on May 19 and the very next day AE and Noonan flew it to Oakland to pick up the new stamped envelopes. Their return to Burbank to spend the night was the unpublicized start of the second world flight attempt. The next morning GP and mechanic Bo McKneely joined them for the flight to New Orleans via Tucson. The following day it was on to Miami where the announcement was made that the world flight had begun.

LTM,
Ric


Subject: RE: Distress calls
Date: 11/10/99
From: Simon Ellwood and others

Regarding the reasons why no further calls were heard from AE after the 08:46 "Changing to 6210" call, and Elgin Long's contention that fuel exhaustion immediately following that call prevented AE from making more calls on 6210Hz:

Wasn't this debated quite some time (maybe a year) ago on the forum, where the phenomenon of radio wave "skip" was proposed as a likely reason for the lack of 6210Hz messages?

I recently re-read an excellent TIGHAR Tracks Vol.10 No. 2 (Autumn 1994) article , in which the very plausible theory was proposed that the L10E's position at the point of frequency change was within the "usable" skip band of 3105Hz, but within a "dead" skip zone of 6120Hz, thus explaining why no messages were received on the latter. The article goes on to propose a band extending from 40 miles out to 60 miles in which only 3105Hz could reliably be used. If the L10E was indeed in this band, it would neatly explain the strength five signals on 3105Hz, and give rise to unreliability on 6210Hz, possibly explaining no signals on this frequency.

I haven't seen this theory mentioned in the recent discussions - has it been show as an unlikely explanation?

What say our forum radio experts?

I would also like to add to the view expressed by some of the forum's pilots (and others) that it seems unlikely that fuel exhaustion immediately after the last 3105Hz call was the reason for the loss of contact. I reason this from the content of the last message.

It seems to me (those dangerous words again!) that on such a challanging flight - at such a critical point, AE could not be other than acutely aware of the exact fuel state (to within the accuracy of the gauges), and at the point of the last 3105Hz transmission, had she been on the point of exhausting the last fuel then she would have expressed this fact with some urgency......."HELP - I'm running on vapour - this may be our last call, we think our position is............" or something along that vein.

Instead she's still at this point preoccupied with establishing contact with Itasca.

LTM (who always knows how much fuel she has)
Simon #2120


From Ric

The theory that the known skip characteristics of 6210 Khz explain the silence that followed the 08:43 transmission (some interpret the log as 08:46) has been challenged rather convincingly by Bob Brandenburg in a message he sent to me on October 11, 1999. I had asked him:

>When we first considered this project back in 1988, the former USAF navigator
>(Tom Gannon) who explained the navigational logic to us also maintained that,
>in his experience, the characteristics of 6210 were such that at the supposed
> distance of roughly a hundred miles, ITASCA would be in a very questionable
> reception area. A later look at a 1937 USN graph depicting skip distances to
> be expected under various conditions seemed to support that. Does this make
> any sense to you?

To which Bob replied:

>No.
>
>6210, nor any other frequency, has any such "characteristics". Ionospheric
>signal propagation between two points at any frequency is a complex function
>of many factors. These include, inter alia, month, day, and local time (sun's
>altitude is a factor), sunspot number (which determines the intensity and
>vertical distribution of ionization in the ionosphere's "layers"), and the
>vertical-plane radiation pattern of the transmitting antenna (which
>determines the antenna's radiation efficiency, and thus radiated power,
>at the elevation angle corresponding to the point in the ionosphere where
>the signal is refracted back to earth).
>
>It's also worth noting that sunspot activity varies sinusoidally on an 11-year
>cycle, which further complicates the task of making generalizations about the
>propagation characteristics of a given frequency.
>
>The idea of "skip" distance is a carry-over from the early days of HF radio when
>knowledge of the ionosphere's structure was primitive compared to what we
>know today. I'm familiar with USN graphs of the sort you mention. After
>WW-2, they were issued to the fleet in a publication called DNC-14, and were
>useless for any practical application. As I recall, DNC-14 was discontinued
>in the mid-60's.
>
>The old notion of "skip" distance was based on the belief that the ionosphere
>acted like a mirror and that all upgoing energy from the transmitter antenna
>was reflected downward toward the receiving antenna at a single point.
>According to this theory, no energy was returned to the earth at intermediate
>distances, hence no reception was possible at intermediate distances. We now
>know, and have known since the late 50's or so, that radio energy is not
>reflected by the ionosphere. Rather, it penetrates into and is refracted by the
>ionosphere, suffering energy absorption losses along the way. The degree of
>penetration, and the time required to effect refraction, is a function of the
>frequency, the angle of incidence of the radiated signal, and the density of free
>electrons in the ionosphere, which in turn depends on the state of ionization,
>which varies with the sun's altitude, and the sunspot number . Energy
>leaving the transmitter antenna is not confined into a narrow vertical beam.
>It leaves the antenna in a fan-shaped vertical pattern of rays with power
>densities varying as a function of elevation angle. Each ray enters the
>ionosphere at a different angle than its neighbors, and therefore experiences
>different degrees of penetration and absorption loss during refraction.
> Because of the this behavior, there is refracted energy returning to earth
>everywhere between the transmitter and the receiver, provided that the
>frequency does not exceed the maximum usable frequency (MUF) for the
>path. The MUF is the highest fequency that will be refracted by the
>ionosphere under the conditions extant at the time of transmission. Any
>higher frequency will penetrate through the ionosphere and
>will be radiated into space.
>
>In case you're wondering, the MUF was significantly higher than either 3105 or
>6210 on all of the signal paths I've looked at so far.
>
>Some people, typically hams, still speak of skip distance, but it really doesn't
>exist unless the MUF is exceeded.
>
>It is often said that it is possible to have skip effects in one direction, but
>not the other, between two identical stations on the same frequency. Such
>effects result from the fact that the ionosphere is not a homogeneous entity, but
>rather is a swirling conglomeration of partially ionized gases in the upper
>atmosphere, replete with local anomalies, eddy currents, etc. The ionosphere
>does not have layers, per se, although we talk about layers such as D, E, F1, and
>F2. If you could examine a vertical slice of the ionosphere, you would not find
>anything like well-defined layers. You would find ionization everywhere, with
>intensity variations producing smudgy clumpings of intensified ionization at
>various altitudes depending on the Sun's altitude and the sunspot number.
>These clumpings are the "layers". But it's the presence of ionization between the
>layers that causes the ionosphere to be a stratified refracting medium rather
>than a set of concentric spherical mirrors. But the altitude of a given "layer"
>is not always constant with distance. Hence, it's possible for a station at one
>end of a path to be refracting its signal from a "layer" at a different altitude
>than the other station. And depending on the altitude differential, it's
>possible for one staion to hear the other, but not the other way round. But
>that's a function of how much energy is refracted, rather than any "skip" zone
>effect. If the non-hearing receiving station increased its antenna gain enough,
>or if the transmitting station increased its output power enough,
>communications could be established.
>
>Far from suffering "skip" effects on 6210, if Earhart had shifted to 6210 on the
>LOP run to Gardner, and if Itasca had been listening, they would have
>heard her loud and clear to within about 100 miles from the Island.
>
>Sorry for the long-winded dissertation on HF, but I thought it would be helpful
>for you to have at least this highly condensed summary. HF signal propagation
>is a very complex subject and its application to real cases is far from trivial.
>
>LTM,
>Bob

So, as tidy a theory as it was, better facts seem to have done it in ( I hate it when that happens!). It is still interesting to me that Tom Gannon's original idea that there was a reception problem on 6210 that was a function of the distance was based upon his own experience navigating airplanes across oceans and using that frequency. Earhart's apparent lack of concern about imminent fuel exhaustion remains one of the big problems for those who believe that Itasca's failure to hear further messages was due to the flight's termination. Several other facts argue strongly for a different explanation:

- In the last message received, Earhart said she was changing frequencies.
Even today, it is not uncommon for a frequency change to simply not work for undetermined reasons. When that happens, Air Traffic Control does not immediately assume that the flight has crashed. The standard procedure is to return to the last frequency that did work. In Earhart's case, there wasn't one.

- 6210 is known to have been a problem frequency for Earhart's transmitter.
The Chater Report contains a brief report by the wireless operator at Lae who says that "the transmitter carrier wave on 6210 KC was very rough and I advised Miss Earhart to pitch her voice higher to overcome distortion caused by rough carrier wave...".

- Itasca had never heard Earhart on 6210 Kcs.
Whether it was "skip" or something else, it does seem that the most supportable hypothesis for the cessation of transmissions from the airplane after 08:43 is that the flight was experiencing some kind of radio problem.


From David

I'm still puzzled why AE didn't send out a distress call. Will the radios still work if the plane ran out of gas? I understand that she can transmit only if the engines are running? How long would it take for the props to stop spinning if she ran out of gas?


From Ric

Yes. The radios should still work if the plane runs out gas. More than enough power should have been available from the battery for a distress call. If I was the pilot, one of the reasons I really wouldn't want to let the Electra run out of gas in flight is that the props would not stop spinning. NR16020 did not have "full feathering" propellers - that is, the prop blades could not be turned knife-edge into the wind in the event of engine failure. That meant that the props would "windmill" causing terrific aerodynamic drag. The 10E is notorioulsy nose-heavy anyway and, with dead engines, that airplane would probably glide like a toolbox.

A prudent pilot, if faced with an imminent water landing, would elect to call off the show and put the airplane down under power, thus greatly increasing his or her chances for survival. To suggest that Earhart did otherwise is to accuse her of almost suicidal behavior.


Subject: Patch it again, Sam
Date: 11/10/99
From: Mike Everette

To revisit the patch one more time:

I put forth the idea/hypothesis that this patch could somehow have been connected with the antenna modifications made by Joe Gurr to the aircraft sometime during the Lockheed repairs... perhaps the patch was applied to cover the holes left by removal of the trailing wire feed on the belly; or maybe to cover the hole left when the antenna insulator feeding the Vee was relocated; or to cover holes left by removal and relocation of the apex mast for the Vee. Well, it appears that any such repair may have not taken place, because it was undocumented.

Let's rethink this...

Once again I am not an A/P specialist, just a communications person. But WHAT IF the patch wasn't applied by an A/P, or even by Lockheed at all?

Suppose Joe Gurr did it himself? As part of his antenna mods?

How likely would it be that Gurr did such a job without its being entered on the a/c paperwork?

Does anything else about the antenna mods show up therein? (What I'm asking is, could the presence or absence of references to this work indicate whether it was done with official sanction?) I got the feeling from reading the Gurr-to-Goerner letter that this was rather loosely handled.

Food for thought?

73
Mike E.


From Ric

I would be much astonished to learn that Gurr installed such a patch. Skin work like that, involving cutting, bending and riveting aluminum, is not something you do out of the trunk of your car and is not something you do at all if you're not a licensed A&P.

I think we can rule out the belly where the old trailing wire mast was mounted. The repair orders show that whole section as being replaced. However, the relocation of the dorsal mast had to be done while the airplane was still in the Lockheed shop because photos taken in the shop while the airplane was under repair show it in the old location and photos taken the morning after the repairs were signed off show it in the new location. I do not think we can rule out the possibility that Lockheed installed a patch when the antenna was moved, even though it is not specifically mentioned in the repair orders. Those orders were written up when the airplane arrived and describe intended actions, not executed actions. We already know from the photos that disproved our belly-patch 2-2-V-1 hypothesis that the airplane did not end up looking just like the repair orders specified. It is virtually certain that some kind of patching had to be done when the dorsal antenna was moved forward. That the patch matches 2-2-V-1 is, at this point, pure speculation but it's a hypothesis worth testing by whatever means we can find to do so.

LTM,
Ric


Subject: Uncharted Island?
Date: 11/10/99
From: Ignacio

Ric, I believe someone mentioned earlier that detailed satellite sky views of the Pacific Ocean were available on line; was there anyone successful in locating the 400+ miles from Howland to Niku?

Is there a possibility that a then 'uncharted' small island or sand bank in their LOP flight, after the last message was sent, where today may appear on a satellite picture, but was (and maybe still is) 'uncharted' and unknown at the time that AE flew in the area, and possibly have landed there, or were ALL the 400 miles long by line of sight width corridor fully mapped back in the 1930's ?

Regards,
Ignacio


From Ric

That part of the Pacific was once known as the South Seas Whale Fishery and was first mapped by the U.S. Navy in 1840 because it was frequented by American whaling ships. (Gardner Island was named for Massachusetts Congressman Gideon Gardner who owned the Nantucket whaler Ganges which first plotted the atoll's location in 1928. The last scene in Moby Dick is set in that neighborhood.) Early charts actually showed a fictional island called "Arthur Island" out to the west of the line between Howland and Niku but by 1937 the entire area was very well known.


Subject: Artifacts 2-2-V-1 & 2-3-V-2(PN 40552)
Date: 11/11/99
From: Jim Kellen

Have you considered metallurgical analysis of 2-2-V-1? I suspect that over the years there have been changes in purification, processing, forming , etc. of aluminum, that would be obvious to a metallurgist. Perhaps a pre or post 1937 date of manufacture could be established for the aluminum panel.

Additionally there are a considerable number of analysis that could be performed on 2-3-V-2 such as molecular weight distribution, tacticity, impurities, catalyst residue, etc., that might enable a polymer chemist to match the material to a particular manufacturing process, location, or time period for the preparation of the Plexiglas.

I'll bet there were some pretty substantial changes in manufacturing processes of aluminum and Plexiglas beginning about Dec. 8,1941.

I know that this approach does not give you the piece of wreckage with a part number on it that you are looking for, but it could eliminate a lot of possibilities.

LTM,
Jim Kellen


From Ric

Been there, done that.

In the fall of 1996 we went through a huge dog and pony show at Alcoa in Pittsburgh involving several types of metallurgical analysis to samples cut from 2-2-V-1. We learned that:

  1. No, the basic alloy formula for 24ST Alclad (now known as 2024) has not changed since 1936. There is no way to "date" aluminum on that basis.
  2. The remnant of original Aloca labeling on the artifact indicates that the stock from which it was made was probably manufactured before 1939.
  3. The metal in the samples had undergone a significant reduction in ductility - that is - it had become less flexible and more brittle than it should be. This was due to the metal having been heated to about 300 degrees F, more than you can get from just exposure to the sun but not as much as if it was actually in a fire.

Previously, of course, the artifact had been examined at the NTSB lab in Washington and by an FAA expert in crash investigation. We have a tremendous amount of information about this artifact and how it probably got to look the way it does. We just don't know where it came from.

The situation with 2-3-V-2, the shard of plexiglass that seems to match Lockheed Part No. 40552 (the cabin window of the Model 10), is similar but simpler. An examination by ther Winterthur Conservation Laboratory here in Delaware confirmed that the material is polymethylmethacrylate (PMMA) originally patented in the U.S. by Rohm & Haas under the name "Plexiglas" and by DuPont as "Lucite" and by somebody else in Britain as "Perspex." It's all the same stuff and, as with basic aircraft aluminum, hasn't really changed since the 1930s.

LTM,
Ric


Subject: Re: Plan B
Date: 11/12/99
From: Greg

I enjoy the forum and understand that the basis of so much here is in the letters indicating that if the airplane was transmitting it must have been on the ground, and that other anecdotal evidence at Niku seems to fit. I especially find the line of reasoning about the possible loss of the DF sense antenna during the takeoff roll at Lae a logical basis for the loss of direction finding capability at Howland. But the idea of leaving the area near Howland and going on to an alternate several hundred miles away with an unknown fuel situation is not logical unless it was planned. Was there any evidence that she had planned alternates in previous flights? If so is ther any information about how much fuel reserve she considered?

\_ Greg _/


From Ric

It's really not a simple matter of proceeding to an alternate and remember that it's Noonan who was in charge of the navigation. We do know that a 20 percent reserve was considered to be a standard for long distance flights. The theoretical scenario goes something like this:

Sunrise, about 17:30 Greenwich, somewhere about 200 miles west of Howland: Fred says, "Okay, got it. We're now on this Line of Position and I know what ground speed we're making. We'll just carry this line forward and, if we're on course, at about 19:00 Greenwich we should see Howland. Just to be sure, let's get Itasca to take a bearing on us. "

At her next scheduled broadcast time (17:45) AE asks Itasca for a bearing and says she's approximately 200 miles out but hears nothing in reply. Half an hour later at her next scheduled transmit time (18:15) she tries again. Still no luck.

Perhaps she tries again at 18:45 but Itasca is calling her on 3105 at that time and so is blocking any incoming signal. At about 19:10 Greenwich Fred says, "Hmmm. We should have seen Howland by now. I know that it's either off to our left at 337 degrees or off to our right at 157 degrees. If we could only get a radio bearing we'd know which way to go. If I had known we weren't going to get any help from DF bearings I'd have flown an offset but now it's too late. We're on the line and we're starting to burn into our fuel reserve. Try again AE."

At 19:12 Earhart transmits:

We must be on you but cannot see you, but gas is running low. Been unable to reach you by radio. We are flying at a thousand feet.

She listens very carefully but still hears no reply.

Fred says, "Okay let's try it the other way. Tell them we're not getting anything on 3105 and ask them to send us a signal we can home on with our loop."

At 19:28 Amelia transmits:

We are listening but cannot hear you. Go ahead on 7500 with a long count either now or on the scheduled time on half hour.

She immediately hears Morse code (dit dah, dit dah, dit dah...) on 7500 but can't get a null or "minumum" and so can't get a bearing on the signal. But at least she now knows that Itasca can hear her so she tries yet again to get them to take a bearing on her.

At 19:30 she transmits:

We received your signals but unable to get a minimum. Please take bearing on us and answer 3105 with voice.

No reply.

Fred says:

"This just isn't working so we've got to do something that WILL work. There are three islands on this line - Howland, Baker and two islands down in the Phoenix Group. We don't know where we are on the line but we can be real sure there is land off to our right. We can afford to look up the line to our left for a little way, but if we're going to be sure of not having to put this airplane in the drink we MUST head southeast while we still have enough fuel to reach land in a worst case situation."

Perhaps Amelia tries to contact Itasca again at her next scheduled time (19:45) but Itasca, once more, is blocking 3105. By the next scheduled time (20:15) they have pretty much given up on getting any help from the Coast Guard and are proceeding southeastward on the line of position - the only course of action that stands a reasonable chance of saving their lives. About the only other thing they can try is changing frequencies. Earhart transmits:

We are on the line 157 337. Will repeat message. We will repeat this on 6210 kilocycles. Wait. And a few moments later: We are running on north and south line.

Still nothing. Maybe they try again half an hour later. Maybe they don't. But Plan B works and they reach land while they still have enough fuel to select a good landing spot and make a safe landing.

That's the theory anyway.

LTM,
Ric


Subject: The Line of Position
Date: 11/11/99
From: Mark Prange

>......[the] sun rises at a slightly different time
>for every point along an east/west line. With your trusty almanac you can
>tell just what LOP you're on when the sun rises for you.

The navigator can compare his sunrise time with what he had calculated for the same altitude over Howland; for each 4 seconds that the observed sunrise is later, the observer is a longitudinal minute--very nearly a nautical mile in equatorial latitudes--west of the LOP. Using a table which shows the converion between arc and time would be the quickest way to get an idea of the displacment; or just dividing the interval (in seconds) by 4 accomplishes this.

What almanac(s) did Noonan have for the flight? Were air almanacs published for 1937? (For 1937 I know of five almanacs--the American Ephemeris and Nautical Almanac, and from references in its preface: the British Nautical Almanac, the German Berliner Jahrbuch, the French Connaissance des Temps, and the Spanish Almanaque Nautico).


From Ric

All we really know for sure is what was aboard the airplane for the first attempt. The Luke Field Inventory lists:

American Nautical Almanac 1937

List of Coast Stations & Ship Stations

List of Aeronautical Stations and aircraft stations

List of Stations performing special services

Navigation tables for Mariners and Aviators


Subject: Crawling all over the Phoenix Islands
Date: 11/13/99
From: Tom King

In a recent post, Don Jordan indicated that he found it strange the Electra hadn't been found on Nikumaroro, if it was there, because people had "crawled all over" the Phoenix Islands. We've beaten this horse before, but maybe we need to do it again.

1. The only pre-TIGHAR people who "crawled" (sic) all over the Phoenix Islands looking for Earhart and Noonan, as far as we know, were the U.S.S. Colorado pilots, who spent perhaps 20 minutes flying over Nikumaroro and equivalent times over other islands, landing only at Hull. Michael Real says they definitely should have seen the Electra if it was on the reef at Niku; others with experience in search and rescue say there are lots of ways they could have missed it. Murphy's Law suggests that Real is over-confident.

2. In late 1937 Harry Maude, Eric Bevington, and a group of I-Kiribati delegates spent two days on Nikumaroro assessing its eligibility for colonization. They were not looking for airplanes or Earhart. Niku is not an easy place to find things even if you're looking for them and know where to look (The only case we know of where anybody has found anything in a few days is TIGHAR's 1996 expedition to the windward side, which with much guidance from state of the art remote sensing was able to navigate pretty directly to the water collection device). In any event, according to both Maude and Bevington, they DID observe signs that someone had recently been on the island.

3. There were I-Kiribati colonists on the island from late 1938 until 1963. They weren't looking for airplanes or Earhart, but we have documentary and anecdotal evidence that they found suspicious human remains and artifacts, and both anecdotal and archeological evidence that they found airplane parts, some of which are more consistent with an Electra than with any other aircraft. What do you want, Don, a sworn affidavit?

4. During World War II there were U.S. Coast Guardsmen on the island, and repeated visits by U.S. aircraft. Members of the Coast Guard team tell us that they didn't often go very far from their base at Ameriki, and there's no evidence that they ever searched for Earhart or the Electra. Their base was as far from the currently hypothesized landing site on Nutiran as you can get and still be on the island.

5. The New Zealand survey party, on the island in late 1938 and early 1939, is a puzzle. Its members mapped Nutiran and should have been able to recognize airplane parts; if there was aircraft wreckage there, why didn't they see and/or report it? We can hypothesize, but we don'tknow. We need to pursue this, and we need help in New Zealand to do so.

So, there have been quite a few people in the Phoenix Islands since 1937. Most of them weren't looking for Earhart or the Electra, but some of them reported things that read very much like the remains of one or the other. It would be poor practice, at best, to ignore this evidence because of the negative evidence provided by the Colorado pilots and the New Zealand surveyors.

LTM (who'd sure like to find a survivor of the survey party)

Tom King


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