Is 2-2-V-1 a Piece of the Sydney Island Wreck? Update #5

In my last post I mentioned that I was unable find any measurement data on TIGHAR’s web site corroborating TIGHAR’s often-made claim that 2-2-V-1 is piece of .032 inch thick of 24ST aluminum sheeting. Ric Gillespie recently remarked on TIGHAR’s online forum that three sources had examined 2-2-V-1 and found it to be .032 inches thick [1].  When I checked reports these sources had submitted to TIGHAR [2,3,4], however, I couldn’t verify that what Gillespie said was actually true. Some of the reports do say that 2-2-V-1 is .032 inches thick, but they seem to be restating the thickness value reported by TIGHAR rather than reporting their own measurement results.

A long-time TIGHAR observer who read my post pointed me to a document on the TIGHAR web site that does provide an actual thickness measurement for 2-2-V-1. In 2015, Lehigh Testing Laboratories in New Castle, Delaware performed chemical and mechanical tests on several specimens of aluminum sheet submitted by TIGHAR, including a specimen cut from 2-2-V-1 [5]. A table on page five of the report listing the measured dimensions of each specimen reports that the 2-2-V-1 specimen was found to be .030 inches thick.

This measurement result raises the possibility that 2-2-V-1 is not a piece of .032 inch 24ST aluminum sheet as TIGHAR has long supposed it to be, but instead that it is a piece of .028 inch 24ST aluminum sheet. Note that I’m talking here about nominal thicknesses, not actual thicknesses, of aluminum sheeting. As discussed in my last post, at the time that artifact 2-2-V-1 was produced the thickness tolerances for Alclad 24ST sheet were .0025 inches for both nominal thicknesses, .028 and .032 inches. This means that nominal .028 inch 24ST aluminum sheet manufactured back then might actually be as much as .0305 inches thick, and nominal .032 inch 24ST aluminum sheet might be as little as .0295 inches thick. A thickness of .030 inches falls within the acceptable ranges for both nominal thicknesses and so it isn’t possible to know from this one measurement whether 2-2-V-1 was fabricated from a piece of .028 inch or .032 inch aluminum sheet.

The same person who pointed me to the Lehigh Laboratories thickness measurement pointed me to a thread on TIGHAR’s online discussion forum, excerpted below, in which Ric Gillespie reported his own thickness measurement results for 2-2-V-1 [6].  This part of the discussion was prompted by TIGHAR’s announcement that Lehigh Testing Laboratories would be analyzing specimens from 2-2-V-1.

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TIGHAR announcement quoted by forum member:  Lehigh Testing Laboratories, Inc. was recommended to TIGHAR by Prof. Eager at MIT as the best lab for trying to learn more about 2-2-V-1 (and other aluminum artifacts) through materials analysis.  By pure coincidence, LTL is located in Wilmington Delaware about 45 minutes from TIGHAR HQ. I contacted LTL and dropped Tom Eagar's name.  They responded with enthusiasm and today we set out a program of testing that should give us the answers to a number of important questions.  Those answers could confirm our fondest conclusions about 2-2-V-1 or they could blow them out of the water... I won't try to list the alphabet soup of technologies LTL will be using to do this work.   They're doing this pro bono because such is TIGHAR's reputation in the scientific community that they consider it an honor to be asked to help with our investigation. What they'll be doing represents thousands, perhaps tens of thousands, of dollars worth of work if hired at commercial rates.  The results we'll get will be scientifically sound, whether or not they're what we want to hear.

Forum Member:  Would it be possible to have LTL confirm the gauge of the aluminum?  I believe the NTSB is the only one that measured it at .032, and I think at least one of their other measurements was slightly off (the convergence of the rivet rows?).  It would be helpful to know for sure what the gauge is.  Just a suggestion.

Gillespie:  Your belief is in error. The thickness of the sheet has been checked many times by many people.  All it takes is a micrometer.

Forum Member:  Alas I have no micrometer at my disposal at the moment nor access to the piece and am therefore dependent upon the written reports of others in this regard.  Could you please direct me to a source(s) that describes and documents any of the many gauge measurements that were made (other than the NTSB report already mentioned), preferably one that includes a description of the tolerance levels involved.  Thank you.

Gillespie:  Okay.  Here's a written report especially for you. I have a micrometer and I have access to the piece and I have measured it numerous times. It's .032".  You can choose not to believe me and wait for the LTL report which will include much more detail.
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Gillespie’s answer may be flippant, but it nevertheless contains some useful information. His belief that 2-2-V-1 is a piece of .032 inch 24ST aluminum sheet is based at least in part on multiple thickness measurements that he himself made using a micrometer. But remember what Gillespie said in questioning Tom Palshaw's micrometer skin thickness measurements on the NEAM C-47 wing [7]:

“I know from experience that measuring skin thickness with a digital micrometer is difficult and frustrating.  Measure three times and get three different answers. With a little confirmation bias you can get any result you want.”

Tom’s follow-up measurements made using an ultrasonic thickness gauge show that Tom’s original micrometer measurements were correct. I think it’s fair to ask whether Gillespie’s own thickness measurements on 2-2-V-1 might have suffered from confirmation bias. When Gillespie made his measurements, what sheet thicknesses did he think 2-2-V-1 might have been manufactured from? Current aluminum product catalogs like the one reproduced below don't list a sheet thickness between .025 and .032 inches for 2024-T3 Clad aluminum, the modern designation for 24ST Alclad. As discussed in my last post, Alcoa product literature from the early 1940s list .028 inches as an available thickness for Alclad 24ST sheet. Did Gillespie know that when he made his measurements? I wonder if Gillespie arrived at his firmly stated .032 inch thickness for 2-2-V-1 through the following process:

1. Gillespie measures 2-2-V-1’s thickness several times with a micrometer; his measurement results cluster around some value between .032 inches and .025 inches, but closer to the former value;
2. Gillespie knows that Alclad 2024 aluminum sheet is currently produced in nominal thicknesses of .025 and .032 inches but is unaware that decades earlier it was produced in a nominal sheet thickness of .028 inches;
3. Since Gillespie’s micrometer measurement results for 2-2-V-1 are closer to .032 inches than to .025 inches, he concludes that 2-2-V-1 is a piece of 24ST Alclad sheet of .032 inch nominal thickness.

Thyssennkrupp Aluminum Stock Guide [8]

If any readers out there know of TIGHAR data that convincingly settles the matter of whether 2-2-V-1 is a piece of nominal .028 inch of .032 inch aluminum sheet, please let me know where to find it. If there is no such data — and I suspect that there isn’t — TIGHAR needs to arrange to have quality measurements made to try to settle this question.  Tom Palshaw noted in his most recent report update that factors such as corrosion, shape, installed fastener effects, and stress induced changes to original dimensions would need to be carefully considered in making thickness measurements on a beaten up, weathered piece of aluminum sheet like 2-2-V-1, and so this is not a job for an amateur wielding a micrometer, with all due respect to Ric Gillespie.

Why is it important to accurately characterize 2-2-V-1’s thickness? Tom Palshaw has shown that 2-2-V-1’s rivet pattern matches the rivet pattern on the upper wing of a C-47 at the New England Air Museum (NEAM). It is reasonable to think that the rivet pattern match would extend to many other C-47s, including the C-47 that crashed on Sydney Island. Tom has confirmed through ultrasonic thickness gauge measurements that NEAM C-47 wing skin is .032 inches thick at the location of interest, the same thickness that TIGHAR has long reported for 2-2-V-1. C-47 repair manuals indicate that the skin of a C-47 should be .028 inches thick at the location of the rivet pattern match, and so it is not a sure thing that the Sydney Island C-47 would also have a seemingly non-standard .032 inch skin thickness at the matching location. On this basis Ric Gillespie can say that the rivet pattern match to the NEAM C-47 wing is a “crazy coincidence”,  and TIGHAR’s claim that 2-2-V-1 is a piece of Amelia Earhart’s Electra can perhaps limp along, badly wounded but not dead. But the .030 inch thickness value measured by Lehigh Testing Labs suggests that if 2-2-V-1 might really a piece of nominal .028 inch 24ST Alclad.  If careful thickness measurements show this to be true, there would be no reason left to think that 2-2-V-1 wasn’t a piece of the wing of the Sydney C-47 wreck. The match in rivet patterns between 2-2-V-1 and the NEAM C-47 wing makes it reasonable to think that the Sydney C-47 wing matched 2-2-V-1’s rivet pattern at the location of interest. If 2-2-V-1 is nominal .028 inch aluminum sheet then it matches the thickness for a C-47 wing at the matching location given in repair manuals. There would be no physical attribute of 2-2-V-1 that can't be matched to a C-47 wing. The claim that 2-2-V-1 is a piece of Amelia Earhart’s Electra would truly be dead.

Comments, corrections, additional relevant facts, differing viewpoints, etc., are welcome.  Send to gardnersghost@gmail.com
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Footnotes/References
[1] https://tighar.org/smf/index.php/topic,2074.msg43572.html#msg43572
[2] (NTSB) https://tighar.org/Projects/Earhart/Archives/Documents/NTSB_Report/ntsbreport.html
[3] (MMR) https://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Artifact2-2-V-1/MMR%20Project%20No.%20128927%20Report.pdf
[4] Letter from MIT Professor Thomas Eagar to Ric Gillespie https://tighar.org/wiki/2-2-V-1#cite_note-3
[5] The Lehigh Testing Laboratories Report can be downloaded at: https://tighar.org/Projects/Earhart/Archives/Research/Bulletins/75_Findings2-2-V-1/75_Report_of_Findings_2-2-V-1.html
[6] https://tighar.org/smf/index.php/topic,1490.msg35664.html#msg35664
[7] https://tighar.org/smf/index.php/topic,2074.msg43575.html#msg43575
[8] http://www.tkmna.com/wcm/idc/groups/internet/documents/web_content/mdaw/mdiy/~edisp/d_004646.pdf

Is 2-2-V-1 Piece of the Sydney Island C-47 Wreck? Update #4

Since my last post on the topic of Tom Palshaw’s report, there have been new developments that are worth discussing. In a recent post on TIGHAR’s online discussion forum [1], Ric Gillespie rejected the report’s conclusion that TIGHAR Artifact 2-2-V-1 is a piece of the wing of a C-47 transport plane that crashed on Sydney Island. Gillespie writes:

“TIGHAR Artifact 2-2-V-1 did not come from a C-47.  The Wing Plating diagram in the C-47 structural repair manual shows the skin thickness in the entire area where the rivet pattern allegedly matches 2-2-V-1 is .028".  The artifact's skin thickness is .032”

Tom Palshaw measured the skin thickness on the C-47B wing at the New England Air Museum as .032 using a micrometer at the edge of the skin.  .004" is an easy error to make. It's a small but important discrepancy.  The NTSB lab, Professor Eager at MIT, and the Massachusetts Materials Research metallurgical lab all measured 2-2-V-1 as .032”.

The C-47 manual dates from September 1942 and was updated in 1945.  There is no indication that the basic structural components of the wing were changed. With this new information, the rivet pattern on the C-47 wing, although remarkably similar to the artifact, becomes another of the crazy coincidences we sometimes encounter.”

In response to this critique, Tom Palshaw has updated his report with new skin thickness measurements on the NEAM C-47 wing at the location of interest. These measurements were made by a level 2 nondestructive testing technician from Bombardier Business Aircraft Service Center using an ultrasonic thickness gauge. I take it that this technique is not prone to sort of errors that Ric Gillespie suggests might have afflicted Tom’s original measurements.  Five ultrasonic thickness gauge measurements yielded skin thicknesses of 0.032, 0.031, 0.032, 0.031, and 0.032 inches. These new measurements confirm that the skin of the NEAM C-47 wing at the location of interest is the same thickness that TIGHAR has reported for 2-2-V-1.

 Wing location matching 2-2-V-1 is marked in yellow (Markup by Palshaw of a DC-3 repair manual; See Ref. 8)

As Ric Gillespie points out, C-47 repair manuals indicate that the skin of the NEAM C-47 wing should be .028 inches thick at the location of interest. It isn’t clear why the NEAM C-47 wing’s skin at the location of interest is thicker than repair manuals indicate it should be. Damaged aircraft skin is often replaced with sheeting in the next higher thickness produced by manufacturers, which in this case would be .032 inches thick. Tom tells me he’s sure that at the location of interest the C-47 wing skin is original factory-installed Alclad 24ST aluminum alloy sheeting, not a later repair. For what it’s worth, I’ll note that .028 inch 24ST aluminum alloy sheeting is not listed as a standard size normally carried in stock in 48 inch widths in the Alcoa's Aluminum in Aircraft published in 1941.  Would sheeting of that width be needed for fabricating the skin at the location of interest on the C-47 wing? If so, perhaps this is a clue that should be pursued in understanding why the NEAM C-47 wing skin is .032 inches thick at the location of interest. Something else that suggests .028 inches is not your typical aluminum alloy sheet thickness: the 1943 version of Aluminum in Aircraft has only one mention of .028 inch aluminum -- in a table of sheer strengths of spot welds for various metal thicknesses

Aircraft sheet metal thickness table, Aluminum in Aircraft, Published by Alcoa in 1941

Spot weld shear strength table, Aluminum in Aircraft, Alcoa 1943

As things now stand, Tom Palshaw has shown that a location on the wing of the NEAM C-47 closely matches 2-2-V-1 in terms of rivet line spacing, rivet pitch, irregularities in pitch of its -5 rivets, and that it has the same .032 inch thickness that TIGHAR has reported for 2-2-V-1. The NEAM C-47 wing and 2-2-V-1 match in every physical attribute determined so far.  From the standpoint of physical dimensions the match between 2-2-V-1 and the NEAM C-47 wing has been better established than the match between 2-2-V-1 and Amelia Earhart’s Electra. As discussed in my last post, past TIGHAR efforts have failed to demonstrate that 2-2-V-1 fits within the boundaries TIGHAR defined for the putative source location on Earhart’s airplane, the window patch installed at Miami in 1937.

The letters ‘AD’ that are faintly visible on the artifact’s surface are another feature that is consistent with the idea that 2-2-V-1 is a piece of the Sydney Island C-47. To help factory workers identify aluminum sheet stock, Alcoa applied material markings to the aluminum sheeting it produced. The Aluminum Markings web site documents a clear trend in how Alcoa’s material markings for Alclad 24ST aluminum sheeting that aircraft skins are made of changed over time.  Photos of aircraft manufactured before 1942, including Amelia Earhart’s Lockheed Electra, consistently show the marking to be  ‘ALC 24ST’.  Photos of aircraft manufactured from 1942 onward predominantly show the marking to be  ‘ALCLAD 24 ST’, though some photos show aluminum aircraft parts marked ‘ALC 24ST’.  So the photographic evidence —a lot of it— indicates that by early 1942,  had Alcoa started to mark 24ST Alclad sheeting it manufactured with a new material marking, ‘ALCLAD 24ST’. This line of evidence therefore tells us that the window patch attached to Earhart’s Electra in Miami in 1937 could not have the letters ‘AD’ seen on 2-2-V-1 because because Alcoa didn’t start using the ‘ALCLAD 24 ST’ material marking for several more years.

Remnant of 'AD' on Artifact 2-2-V-1. See reference [5] for source

B-25 factory photo, circa 1942. Note 'ALCLAD 24S-T' markings to left of female worker

Underside of Earhart's Electra, circa 1937. The material marking reads 'ALC 24ST'. Full photo at upper right

The similarities between the NEAM C-47 wing and 2-2-V-1 are just too great to be dismissed as a ‘crazy coincidence’.  The problem with the assertion that the wing of the Sydney Island C-47’s can’t be the source of 2-2-V-1 because repair manuals indicate that skin at the location of interest shouldn’t be .032 inch thick is that an actual C-47 wing, the one at NEAM, shows that C-47 wings were not always manufactured with the skin thicknesses indicated in repair manuals.

The right thing for TIGHAR to do, given the evidence Tom Palshaw has produced, is gather evidence that might shed further light on the Tom’s conclusion that 2-2-V-1 is a piece of wreckage scavenged from the Sydney C-47. To misrepresent a piece of the Sydney C-47 wreck site as a piece of Amelia Earhart’s Lockheed Electra would be a disservice to those who died in the Sydney C-47 crash and to the crew of the Electra. Surely TIGHAR would want no part of such an abomination.

TIGHAR should carefully document how well the rivet pattern on the NEAM C-47 wing matches 2-2-V-1. Laying 2-2-V-1 over the NEAM wing at the location of interest and documenting the match with photographs would take no more than ten or fifteen minutes to do. While at NEAM to conduct this comparison, TIGHAR can also demonstrate whether or not 2-2-V-1 fits within the boundaries defined for the dimensions of the Miami window patch in a previous TIGHAR study [2]. This too would be a simple exercise that would only take minutes to carry out. These comparisons should be done with the full cooperation of Tom Palshaw. I find it odd that Ric Gillespie visited NEAM only a few weeks ago to conduct measurements on the NEAM Electra but gave Tom Palshaw no advanced notice of his visit.

Another basic piece of information that needs to be better documented is 2-2-V-1's thickness. Although TIGHAR has repeatedly stated that 2-2-V-1 is .032 inches thick, I can find no clear information about how 2-2-V-1’s thickness was determined. A few posts further along the discussion thread in which Ric Gillespie dismisses Sydney Island C-47 as the source of 2-2-V-1, he comments that “The NTSB lab, Professor Eager at MIT, and the Massachusetts Materials Research metallurgical lab all measured 2-2-V-1 as .032” [3]. I’ve reviewed all three of these sources [4,5,6] and as best I can tell, 2-2-V-1’s thickness was not actually measured by NTSB, MIT or the metallurgical lab. Where the thickness of 2-2-V-1 is stated in these sources the authors appear to simply be stating the artifact thickness reported to them by TIGHAR. There certainly is no description in any of these sources of a measurement method or a presentation of actual measurement data.

Surely the 0.32 inch thickness TIGHAR has reported is based on an actual measurement, but how that measurement was made and what the actual measurement result was has never been reported, as far as I know. Did Ric Gillespie make these measurements using a micrometer? If so, then the claim that 2-2-V-1 is .032 inches thick is based on the same measurement technique that Ric Gillespie has said could easily be in error by .004 inches. Gillespie in a later post on the same TIGHAR discussion forum states: “I know from experience that measuring skin thickness with a digital micrometer is difficult and frustrating.  Measure three times and get three different answers. With a little confirmation bias you can get any result you want” [7]. Here it is worth quoting something Tom wrote in his latest update on the NEAM C-47 skin thickness measurements:

“Measuring the thickness of a new sheet of ALCLAD is as simple as using a standard 1" micrometer. The metal is smooth, flat, and clean. Once the metal has been installed, or exposed to the elements, several factors can affect the accuracy of the measurement. These include a paint coating, corrosion, shape, installed fastener effects and stress induced changes to its original dimensions.”

2-2-V-1 is not a fresh new sheet of aluminum alloy, it is a beaten up sheet of aluminum alloy that undoubtedly has been exposed to the elements for many years. The Massachusetts Materials Research Laboratory report on 2-2-V-1 describes it thusly:

“Overall, the artifact presented a grey, oxidized aluminum appearance with isolated regions of buff-colored calcareous deposits and thin, green discolorations. Both the buff and green deposits were reported to have been previously tested and found to be consistent with coral and algal growths”

Note that before making his new measurements on the C-47 wing, Tom gently removed accumulated surface coatings from his measurement locations using a Scotchbrite pad. Were surface deposits accumulated in the years of exposure of 2-2-V-1 to the elements removed before its thickness was measured? Tom points out that at the time artifact 2-2-V-1 was produced, the thickness tolerances for Alclad 24ST sheet was .0025 inches for manufactured sheeting in either the .028 or .032 inch thickness. For all we know, 2-2-V-1’s actual thickness falls within the range falls within the range for nominal .028 inch sheeting, but TIGHAR has erroneously reported it to be .032 inches thick. For example, if 2-2-V-1 was nominal .028 inch sheeting whose actual manufactured thickness was .029 (well within the manufacturing tolerance) with a .001 inch thick coating of weathering/coral/algal residue, and a .001 inch micrometer measurement error was made, the measured thickness would have been .031 inches (.029+.001+.001=.031). The individual making the measurement might have  concluded that 2-2-V-1 was .032 inch thick since this was the closest nominal Alclad 24ST sheet thickness to the measurement result.

Clearly then another thing TIGHAR must do is document what 2-2-V-1’s thickness was when manufactured. Given the .0025 inch manufacturing tolerance, it may not be possible to definitively exclude that 2-2-V-1 was either nominal product thickness, .028 or .032 inches. The determination of 2-2-V-1’s original manufactured thickness is yet another activity that TIGHAR could and should carry out in collaboration with Tom Palshaw. The effects of factors Tom mentions in his update such as shape, installed fastener effects, and stress induced changes to original dimensions would need to be carefully considered.

It would also be useful to accumulate more information about rivet patterns and skin thicknesses of surviving C-47s and DC-3s in museum and private collections. Tom’s update includes ultrasonic measurements of the thickness of the skin of the NEAM DC-3 at the location of interest [8], and there the measurements indicated a skin made of .028 inch nominal sheeting. Accurate skin thickness measurements made on other C-47s and DC-3s might reveal a pattern relevant to the question of whether the Sydney C-47 is the source of 2-2-V-1.

Comments, corrections, additional relevant facts, differing viewpoints, etc., are always welcome.  Send to gardnersghost@gmail.com
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Footnotes/References

[1] https://tighar.org/smf/index.php/topic,2074.msg43572.html#msg43572
[2] Earhart Project Research Bulletin #73, The Window, the Patch, and the Artifact.  https://tighar.org/Projects/Earhart/Archives/Research/Bulletins/73_StepbyStep/73_Step_by_Step.html
[3] See the TIGHAR discussion forum post at reference 1
[4] https://tighar.org/Projects/Earhart/Archives/Documents/NTSB_Report/ntsbreport.html
[5] https://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Artifact2-2-V-1/MMR%20Project%20No.%20128927%20Report.pdf
[6] Links to the MIT emails can be found at https://tighar.org/wiki/2-2-V-1#cite_note-3
[7] [https://tighar.org/smf/index.php/topic,2074.msg43575.html#msg43575]
[8] DC-3s and C-47s are to a great extent the same airplane, the former manufactured for use as a civilian airliner while the latter was made to be a military transport. The wing diagram above comes from a 1940s-vintage DC-3 repair manual

Is 2-2-V-1 Piece of the Sydney Island C-47 Wreck? Update #3

The latest notable response to Tom Palshaw's report is a post on the TIGHAR discussion forum by Ric Gillespie reporting new rivet line spacing measurements for 2-2-V-1 [1]. According to Gillespie:

 “The differences, while not huge (see “Actual v template”.jpg ) are significant when measuring precise alignment with the pattern on the C-47 wing. Palshaw’s template appears to fit the C-47B wing but it does not accurately reflect the artifact.”

The ‘Actual v. template’ figure (see below) is Gillespie’s markup of a photo in the Palshaw report showing a paper template of 2-2-V-1 laid over the New England Air Museum (NEAM)  C-47 wing. The lines on the template were made by Tom Palshaw to indicate 2-2-V-1’s rivet line spacings based on earlier TIGHAR data. The numbers in yellow were added by Ric Gillespie to indicate his new rivet line spacings. I’ve further marked up the photo with the numbers in blue to correct errors in two of Gillespie’s numbers.

Gillespie's new rivet line spacing measurements superimposed on Tom Palshaw's  2-2-V-1 template.

The differences between the new rivet line spacings and those in Tom Palshaw’s template are small, as Gillespie notes. Do these differences matter with regard to the question of whether 2-2-V-1’s rivet lines match those of the NEAM C-47 wing? Tom’s template was a stand-in for 2-2-V-1, which he didn’t have access to when he wrote his report. Rather than concerning ourselves with Tom’s template, let’s consider how well the thing itself, 2-2-V-1, matches the wing. The photo below is a screen shot from the YouTube video of Gillespie and Palshaw comparing 2-2-V-1 to the NEAM C-47 wing in 2017 [2]. At the edge of 2-2-V-1 closest to the camera 2-2-V-1’s rivet hole lines appear align well with those on the underlying C-47 wing. Gillespie’s new measurements don’t appear to disqualify the NEAM C-47 wing as a match for 2-2-V-1, at least at the side closest to the camera. The YouTube video does not provide as good a view of the far end of 2-2-V-1, but neither Gillespie or Palshaw say in the video that the rivet line spacings of the C-47 wing and 2-2-V-1 don’t match.

Direct comparison of 2-2-V-1 to the NEAM C-47 wing

Further along in the same TIGHAR forum post in which Ric Gillespie reports his new rivet line spacing measurements, he writes:

“For the best possible comparison to the C-47A that crashed on Sydney Island, we need to come as close as we can to apples-to-apples. We need to do a detailed examination and measurement of the relevant section on the wing of the closest surviving C-47A by tail number.  We will be doing that later this winter.”

While it would be interesting to see how well 2-2-V-1 matches the wings of other C-47s, surely a careful examination of the NEAM C-47 wing should take precedence over comparisons to other C-47s. All information available so far indicates that the NEAM C-47 wing is a close match to 2-2-V-1. The doubts Gillespie raised in the YouTube video were addressed in the Palshaw report, and since then Tom has found additional matching features, as discussed in my earlier posts. TIGHAR should collaborate with Tom Palshaw to carefully compare 2-2-V-1 to the NEAM C-47 wing to determine just how well they match. Ric Gillespie has written that “TIGHAR is an educational foundation and the Earhart mystery is a perfect vehicle for exploring, demonstrating, and teaching the scientific method of inquiry” [3]. The scientific method of inquiry most definitely is not about ignoring observations that suggest a favored hypothesis is wrong.

If we are to believe that 2-2-V-1 came from the Sydney Island C-47 wreck, it is reasonable to expect proof that 2-2-V-1 matches some part of a C-47.  Likewise, if we are to believe that 2-2-V-1 is a piece of Amelia Earhart’s Lockheed Electra it is reasonable to expect that TIGHAR demonstrate that  2-2-V-1 corresponds to a source location on Earhart’s Electra. According to TIGHAR, that source location is the ‘Miami Patch’, an aluminum alloy sheet that was attached to Earhart’s Electra in Miami to cover a window early on the voyage on which she disappeared. In the photo below taken shortly after it was installed, the shiny new Miami Patch stands out from the more weathered fuselage to which it had been attached.

The newly-installed window patch. Miami, June 1937.

A basic requirement for 2-2-V-1 to be a piece of the Miami Patch is that it must be smaller than the Miami Patch. This is necessarily true because nowhere on 2-2-V-1 is there an original manufactured edge; 2-2-V-1 was clearly torn away from a larger piece of aircraft skin. TIGHAR has stated that 2-2-V-1 fits within the perimeter of the Miami Patch but as far as I know it has never published a photo demonstrating this to be the case. One place where TIGHAR states that 2-2-V-1 fits within perimeter of the Miami Patch is in TIGHAR Research Bulletin #72 [4]. A section titled ‘Do the dimensions of the artifact fit within the dimensions of the patch?’ states:

To answer that question required accurate scaling and the removal of camera-induced distortion from the Miami Herald photo and a photo of 2-2-V-1 pressed down to allow measurement of its full size.  The edges of the patch were straight and riveted, while the borders of the artifact are all failed edges, with one side showing evidence of a line of staggered rivets. If the artifact is a broken-out portion of the patch it must fit within the dimensions of the patch. TIGHAR forensic imaging scientist Jeff Glickman was able to remove the distortion and accurately scale and overlay the photos. The artifact fits nicely within the patch.

The accompanying image of the overlay, see below, does indeed depict 2-2-V-1 as nicely fitting within the boundaries of the Miami Patch. Given 2-2-V-1’s size, the overlay suggests that 2-2-V-1 is several inches smaller than the Miami Patch both vertically and horizontally.

But this overlay must be in error, because actual photos of 2-2-V-1 held close to surviving Lockheed Model 10 Electras show that if 2-2-V-1 fits within the Miami Patch’s boundaries at all, it does so with very little room to spare. TIGHAR Research Bulletin #73 [5] reports the results of an examination of an Electra undergoing restoration in Wichita, Kansas. The report includes the photo below of 2-2-V-1 held close to the exterior of the Wichita Electra’s fuselage, with the perimeter of the Miami Patch outlined somewhat inaccurately with yellow adhesive measuring tape. 2-2-V-1 does not appear to fit within the marked boundaries of the Miami Patch. The ‘Tab’ feature at the bottom edge of 2-2-V-1 extends below the lower boundary of the Miami Patch, which in this photo corresponds to the upper edge of the yellow tape. 2-2-V-1 also overlaps the yellow tape that marks the forward perimeter of the Miami Patch, which in this photo is placed too far forward. As discussed in TIGHAR Research Bulletin #73 itself, the forward edge of the patch had to be tailward of where it appears in the photo [6]. 2-2-V-1 fits within the upper perimeter of the patch, but perhaps only because as 2-2-V-1 is held in this photo it bulges outward, which lessens any vertical mismatch between it and the patch. Remember that since 2-2-V-1 is a remnant of a larger piece of metal, it must not only fit within the perimeter of the patch, it must do so with room to spare. TIGHAR Research Bulletin #73 notes the lack of fit apparent in this photo and explains it as being an effect of perspective, i.e., 2-2-V-1 appears to be larger relative to the fuselage than it really is because it’s slightly closer to the camera. Why this report did not include a photo of 2-2-V-1 pressed against the side of the Wichita Electra to clearly show how well it fits within the required perimeter is a mystery; surely a thin sheet of transparent plastic could have been placed between fuselage and 2-2-V-1 to prevent cosmetic damage to the surface of the airplane if that was a concern.

2-2-V-1 compared to the Miami patch perimeter, Wichita.

If TIGHAR has a photo from the Wichita exercise that properly compares 2-2-V-1 to the Miami Patch’s perimeter, it should publish that photo to support its claim that 2-2-V-1 is a piece of the Miami Patch. If TIGHAR does not have such a photo, it is all the more reason to return to NEAM. NEAM has a Lockheed Model 10 Electra in its collection, so in addition to documenting how well 2-2-V-1 matches the NEAM C-47 wing, TIGHAR can document how well 2-2-V-1 fits within the boundaries of the Miami Patch.

Some time ago Ric Gillespie posted a photo on the TIGHAR Forum similar in composition to the Wichita photo, but using the NEAM Electra's fuselage as the backdrop and the patch perimeter marked with clear adhesive tape.  That photo (see below) shares some of the Wichita photo’s problems, e.g., the forward perimeter is placed too far forward and 2-2-V-1 bulges outward. Additionally, 2-2-V-1 is held at an unlikely angle with respect to the Electra’s fuselage; the lowest rivet line would not span the width of the patch at the angle it makes with the lower boundary of the patch. Gillespie notes some of these problems, but his assessment was nevertheless that "It's not a great photo and the placement is a bit too high and a tad too far forward on the airplane but, as you can see, it all works". But it doesn't all work. 2-2-V-1 extends beyond the upper and lower perimeter of the patch even though its outward bulge reduces the extent of the overlap, and since the forward perimeter is too far forward, it is not clear that 2-2-V-1 is fits horizontally within the Miami Patch's boundaries. Once again I note that 2-2-V-1 must fit with room to spare since it is a fragment of a larger piece of metal.

2-2-V-1 compared to the Miami Patch perimeter, New England Air Museum

TIGHAR claims that 2-2-V-1 is small enough to be a piece of the Miami Patch, but it hasn’t provided clear photographic proof that this is true. It should take less than an hour at NEAM to properly compose a comparison photo that would provide this needed proof. The four borders of the patch perimeter would need to be properly positioned on the fuselage and 2-2-V-1 would need to be pressed against the NEAM Electra's fuselage to minimize bulges and to eliminate effects of perspective.

Comments, corrections, additional relevant facts, differing viewpoints, etc., are always welcome.  Send to gardnersghost@gmail.com
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References

[1] https://tighar.org/smf/index.php/topic,2074.msg43506.html#msg43506
[2]  https://www.youtube.com/watch?v=GlVLyOfsZ3c&t=101s
[3] https://tighar.org/smf/index.php/topic,1999.msg42342.html#msg42342
[4] https://tighar.org/Projects/Earhart/Archives/Research/Bulletins/72_SmokingGun/72_Smoking_Gun.html
[5] https://tighar.org/Projects/Earhart/Archives/Research/Bulletins/73_StepbyStep/73_Step_by_Step.html
[6] In the Wichita photo, the forwaed perimeter coincides with a row of staggered rivets at what is referred to as 'Station 293 5/8'.  TIGHAR Research Bulletin #73 states: "The frame could not be riveted directly to the underlying structure at Sta. 293 5/8 because of the thick lavatory bulkhead on the interior (no way to buck the rivets), so new underlying structure was added just aft of Sta. 293 5/8 to provide something to rivet the frame to".