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[Diane James]

Hi Y'all, this is this long-lurker's first forum post. An e-mail from Marty sent me here.

1) Since the patch would have had to conform to a slight compound-curve, the measurement around the circumference of that curve would be slightly greater than a measurement taken straight across that distance flat.  It's not much of a difference, but the apparent discrepancy in the "too big" theory isn't by much of a difference either. Is that difference in circumferential measurement sufficient to explain why 2-2-V-1 may seem too large to fit?

2) if 2-2-V-1 was pushed violently outward, enough to deform rivet holes, could that have caused stretching in the aluminum sheet such as to expand it to its current measurements?

3) If 2-2-V-1 has been exposed to low-temperature fire, such as for cooking, would the deformation caused by that heating, especially as in repeated heating and cooling from cooking many meals, be sufficient to cause permanent expansion, such that it would now measure larger than when first removed from the aircraft?

4) If 2-2-V-1 shows signs of having been "pried" loose at one edge, as I recall reading, is it possible that the recovered pocket knife might have been the tool?  Could microscopic analysis, such as a forensic lab can do in matching rifling marks on a bullet, possibly match microscopic marks on these artifacts to one another?

Diane

[Ric Gillespie]

1) Since the patch would have had to conform to a slight compound-curve, the measurement around the circumference of that curve would be slightly greater than a measurement taken straight across that distance flat.  It's not much of a difference, but the apparent discrepancy in the "too big" theory isn't by much of a difference either. Is that difference in circumferential measurement sufficient to explain why 2-2-V-1 may seem too large to fit?

2) if 2-2-V-1 was pushed violently outward, enough to deform rivet holes, could that have caused stretching in the aluminum sheet such as to expand it to its current measurements?

3) If 2-2-V-1 has been exposed to low-temperature fire, such as for cooking, would the deformation caused by that heating, especially as in repeated heating and cooling from cooking many meals, be sufficient to cause permanent expansion, such that it would now measure larger than when first removed from the aircraft?

All of that seems to be within the realm of possibility. To me, the most fundamental issue is that the analysis that finds the artifact to be too big to be the patch is based upon the assumption that distances between rivet lines on the airplane in Kansas are identical to distances between rivet lines on NR16020. The assumption is unsubstantiated by any data. Earhart’s Electra was delivered in July 1936 and was the 55th Model 10 built.  The airplane in Kansas was delivered in April 1937 and was the 91st Electra built – nine months and thirty-six airplanes after Earhart’s.  The Lockheed plant is known to have had at least two jigs that were used for framing up Model 10 airframes. The photo below dates from circa December 1934.  It shows Model 10 airframes being framed up and skinned in two jigs. More jigs may have been added as Electra production ramped up.  Ten aircraft were delivered in 1934, thirty-five in 1935, twenty-eight in 1936, forty-four in 1937. In the pre-laser world of the 1930s it seems possible that there were small variations between jigs. It would be interesting to check the distances between rivet lines on several existing Model 10s.

4) If 2-2-V-1 shows signs of having been "pried" loose at one edge, as I recall reading, is it possible that the recovered pocket knife might have been the tool?  Could microscopic analysis, such as a forensic lab can do in matching rifling marks on a bullet, possibly match microscopic marks on these artifacts to one another?

It's an interesting thought but to do that we would have to have the knife blades.  We don't.  We found everything but the blades. The knife was beaten and broken apart with a blunt object in order to remove the blades, presumably to be used for some other purpose (make a spear?).

[Diane James]

That's a super observation, Ric, about more than one factory assembly jig!

I wonder if someone at each of the locations where a Model 10 exists would make a careful measurement of that spacing for TIGHAR and then we could tally the results. It should be quick to confirm or disprove the "different jigs - different spacing" theory; we could know that in days. The idea makes a lot of sense to me, and I'll be impatient waiting to see the data.

[Ric Gillespie]

I wonder if someone at each of the locations where a Model 10 exists would make a careful measurement of that spacing for TIGHAR and then we could tally the results.

I wish it was that easy.  Virtually all Model 10s in museums and collections have undergone extensive "restoration."  Some surviving Electras (such as c/n 1130 at the Naval Aviation Museum in Pensacola, c/n 1015 at the Museum of Flight in Seattle, not to mention c/n 1091 in Kansas) have been completely re-skinned. Any data we recovered from these aircraft would be suspect.  The only Electra serving in guaranteed original (albeit wrecked) condition is c/n 1021, the Gillam wreck in the Misty Fjords Wilderness Area in Alaska.  A TIGHAR team visited the wreck in 2004 - in immensely challenging task.

[Diane James]

...and I presume it goes without saying that you have already determined that the Lockheed folks don't have the jigs stored in a back room somewhere, awaiting consumer demand for more model 10s.  Woulda been nice.

Does TIGHAR have a metallurgical opinion about the part having been stretched by heat and/or what appears to be fluid impact?  Is there a way to non-destructively determine if stretching occurred? Would that stretching account for the apparent size discrepancy?

[Ric Gillespie]

Does TIGHAR have a metallurgical opinion about the part having been stretched by heat and/or what appears to be fluid impact?  Is there a way to non-destructively determine if stretching occurred? Would that stretching account for the apparent size discrepancy?

I've discussed with metallurgists at Lehigh Testing Labs whether stretching due to force or heat might have altered the dimensions of the artifact.  Their opinion is that any such distortion would be very small - far smaller than the inch and a half alleged by the critic's report.

[JNev]

Does TIGHAR have a metallurgical opinion about the part having been stretched by heat and/or what appears to be fluid impact?  Is there a way to non-destructively determine if stretching occurred? Would that stretching account for the apparent size discrepancy?

I've discussed with metallurgists at Lehigh Testing Labs whether stretching due to force or heat might have altered the dimensions of the artifact.  Their opinion is that any such distortion would be very small - far smaller than the inch and a half alleged by the critic's report.

Can you clarfiy, please?  Which critic's report is that, Ric? 

I don't recall an inch and a half 'distortion' being alleged by anyone.

[Ric Gillespie]

Their opinion is that any such distortion would be very small - far smaller than the inch and a half alleged by the critic's report.

To clarify, the critic's report alleges that the artifact is too wide to be the patch.  The report does not allege any distortion. My point was merely to affirm that, in the metallurgists' opinion, if there was distortion it would not be sufficient to account for the discrepancy described in the report.  Quoting directly from the critic's report:

"Conclusion as to the STA 307 ‘vertical brace’ feature:
The STA 307 brace feature cannot align with that corresponding station on the airplane unless the forward edge of the artifact is placed approximately 1 1⁄2” too far forward. This is a disqualifying fit issue for the STA 307 ‘vertical brace’ feature on 2-2-V-1.

Conclusion as to width and fit of the artifact:
At its extreme width, the artifact could fit as the covering with a reasonable degree of excessive edge distance as to the left and right vertical rivet rows. However, this must be discounted because there is a lack of finished edges which should be evident at this full-width article at least at the forward (RH) edge (see RH blue box, Figure 15). Instead we see a fracture zone.
This is disqualifying in the author’s opinion: given the fracture boundaries and considering its full width – which might otherwise coincide handily with the actual covering width, the artifact is physically too wide to be Earhart’s Navigation Window Covering. Any edges surviving at the extremes should be finished edges."

Forum members are urged to read the entire 25 report which can be found on the TIGHAR website at http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/76_Neville_Report/2-2-V-1_Fit_Report_Neville.pdf

[Diane James]

OK, so there is an odd-shaped tear at the top of 2-2-V-1, and if that tear is aligned with where the circumferential fuselage former would be at STA 307, then the patch sticks too far forward by about an inch and a half? Do I have that right, or have I missed something glaring in my newbie-ness?

1) The so-called patch is an external ("scab") patch, which we believe was torn away in an outward direction  from the airframe.  Thus it was forced away from contact with structure at STA 307, not forced into it. Is there a reason to believe the damage at the top of 2-2-V-1 is necessarily caused by or even related to the former at 307?   

2) If 2-2-V-1 were not necessarily aligned with the former, and could be positioned 1 1/2 inches farther aft, does it then otherwise fit in all dimensions?

[Diane James]

I'm still reaching for understanding here.

The vertical stiffener seems to have left quite a visible trace of its position, but I don't see any such residual markings from the horizontal stiffeners. 

1) What do we know about the relationship of the stiffeners to one another?  Did the vertical run underneath the horizontals?  Why do we think that? Do any of the rivet holes penetrate the vertical?

2) What do we know about the mark left by the vertical?  Is it paint, or maybe adhesive?  Is it possibly due to dis-similar metal corrosion where the vertical might have been a thin steel stiffener?  If the horizontals were aluminum they likely would not leave such a trace.

3) The factory structure at STA 307 was cut away at the time of the installation of the special window.  Do we have any reason to believe that the vertical brace on the window patch would necessarily be positioned at that station?  Surely no one would expect that little vertical stiffener to replace the load-bearing capabilities of the factory-installed circumferential former, so why would it need to be located exactly at STA 307 when it's just stiffening a window patch and not carrying structural loads?

[Todd Attebery]

Very good questions about the vertical stiffener.  In any logical (to me anyway) repair to cover the window it seem like they would attach the vertical stiffener with rivets and it would make sense to line it up with Station 307.   But since there are no fasteners, it leads me to believe that what made the impact marks was not considered a structural stiffener.  I envision some sort of interior feature, possibly made from wood, like a desk or a navigators case... something solid that's part of the aircraft but not part of the airframe. 

[JNev]

Diane,

You raise good questions.

I am glad that Ric encouraged readers to thoroughly review my report.  I was a TIGHAR Researcher at the time I wrote that, not a 'critic' per se, by the way.  I began that effort in an attempt to answer off-site criticism stating that 2-2-V-1 was too large (vertically and by implication, horizontally) to fit properly as the patch.  I was encouraged to do so by an administrator on this site.  I hope all will find the report educational, whether one agrees with my own views therein or not.

As to the '307' feature: what was important about that find on the artifact was the possibility that it might align with the normal placement location for any re-established ring former section behind the 'patch' when installed in Miami, or subsequently; were that what the feature related to, it would surely reinforce the idea of 2-2-V-1 being 'the patch'.

What became disappointing to me (YMMV, of course) was that to get that noticeable feature on 2-2-V-1 to align with that station on the Electra - the most logical place for a vertical member to appear (why would one install a replacement vertical stiffener out of alignment with the existing remnants of the 307 ring former?), the artifact had to be slid forward to contact the aft edge of the next skin forward, in the 293 5/8 STA area.  That arrangement, in my view (as stated in the report) is in conflict both with logical placement of the 307 'feature' and what 'should be' the forward edge of the 'patch'.  In making that judgment, I am going by two things as to the forward limits of the 'patch':
1 - The patch logically assumes a similar outer-perimeter footprint to that of the coaming, which is easily defined by looking at the 'Nilla Putnam / Earhart' photo in Miami in which the forward area of the open window coaming is easily viewed, and
2 - An offset of the 'patch' away from (not abutting) the skin edge near STA 293 5/8 IS discernable in several photographs - a point of controversy, apparently, to TIGHAR whereby I am not officially qualified as a photogrammetrist and thereby cannot make more than an amateur statement in that regard.

I simply maintain that the offset (separation of the forward edge of the 'patch' and aft edge of skin near STA 293 5/8) is discernable to the lay eye in numerous photos, and note that TIGHAR herself has at one point or another in the discussion also believed the patch to approximate, logically, the footprint of the coaming.  Further, TIGHAR has not so far established dimensions of the patch as being that large (able to pick-up 307 AND reach the aft edge of that forward skin near STA 293 5/8) - which would be one way TIGHAR might counter my report, if a credentialed photogrammetrist of TIGHAR's approval were able to do so.

Another oddity of the '307 feature' is the lack of fastener holes there - why bother re-installing that missing segment of the 307 ring former only to allow it to simply lie in contact without benefit of stiffening / strengthening fasteners? 

You raise good questions:
What caused that mark? 
Why does it appear on what would be the outer surface of 'the patch', and not inner - where the faying contact surface of the 307 member would logically reside? 

None of the horizontal rivet holes in 2-2-V-1 coincided with the vertical '307' feature that I could discern - but as always, more scrutiny is invited.  Also, 1937 is not reknowned as an era of structural bonding without benefit of mechanical fasteners, so the notion of adhesive in any structural sense is probably not a likely reality.  This feature remains an unanswered enigma on 2-2-V-1 in my view, and could have come about in as simple a way as the artifact itself merely lying across some dissimilar metal object of that 'footprint' for some time by some odd or deliberate way - not necessarily as-installed in any airframe.

Just to be clear, I bore no particular spirit of 'criticisim' at the time of that report on this matter, nor do I now as to 2-2-V-1; it was always merely an artifact to be explored - and not vital to the Earhart case at Niku UNLESS it could be unequivocally proven to BE OF her Electra.  To the extent I may be a 'critic' of TIGHAR would be based in other matters - NOT in the objective review of patch / 2-2-V-1 metrics per se.  I consider my report to be one person's view, nothing more, and offer only that it has been 'peer reviewed' by two other qualified engineering persons (Messrs. Billings and Mark Pilkington, both well experienced in physical metrics and data interpretation as engineers / quality analysts).  The report was also subjected to review by 'the Dayton Commission' here at TIGHAR, including Mr. Aris Scarla of the FAA, and additionally, Mr. Jeff Glickman who has been a significant contributor to TIGHAR in photogrammetry, and Mr. Joe Cerniglia, a frequent commenter and contributor of research here.  All had some degree of questioning - all answered by me, but none offered disqualifying comments to me as to my work in that report.

As Ric has encouraged, I suggest readers take it in for themselves: I am not trying to disprove an Earhart presence at Niku - I have merely offered my most objective review of 2-2-V-1 as a supposed artifact of Earhart's airplane, specifically as to a conjectured fit over the lavatory window (an idea I actually initiated and do not regret, all possibilities deserving some review as I see it).

I hope this answers at least some of your good questions and clarifies my position in this matter, to whatever extent that may be important.  I think it is important because while I may be a critic in some regards, this work must stand objectively clear if it is to have meaning.  That was always the intent.  I also will welcome a well qualified and quantified response to my report from TIGHAR should she find the specific means to counter my views and personal conclusions therein.  Both TIGHAR and myself lack physical access to the actual Earhart Electra and her Miami-installed patch, so we are both forced to work from the historic record, such as it is.  Fortunately for us both, I believe photographic evidence is sufficient, if not as ample as we'd hoped for.

[Ric Gillespie]

I'm still reaching for understanding here.

Welcome to the club.

The vertical stiffener seems to have left quite a visible trace of its position, but I don't see any such residual markings from the horizontal stiffeners.

Yeah there are but they're different from the indication of the vertical stiffener.  I have darkened the attached image so that the markings along the interior where the horizontal stiffeners once were show up better. The markings seem to be spots where there is more oxidation as if the aluminum under the horizontal stiffeners was not as well protected as the surrounding metal.

1) What do we know about the relationship of the stiffeners to one another?  Did the vertical run underneath the horizontals?

Apparently not.

Why do we think that? Do any of the rivet holes penetrate the vertical?

The strange thing is that there is no apparent evidence of the vertical stiffener on the interior of the sheet other than the tear at the top where the vertical stiffener may have been anchored to the circumferential at Sta. 307.

2) What do we know about the mark left by the vertical?  Is it paint, or maybe adhesive?  Is it possibly due to dis-similar metal corrosion where the vertical might have been a thin steel stiffener?  If the horizontals were aluminum they likely would not leave such a trace.

The mark left by the vertical stiffener is perhaps best described as a dent in the exterior surface that was caused by an impact on the interior.

3) The factory structure at STA 307 was cut away at the time of the installation of the special window.  Do we have any reason to believe that the vertical brace on the window patch would necessarily be positioned at that station?

Only that the remaining part of the circumferential would be something the stiffener could be anchored to.

  Surely no one would expect that little vertical stiffener to replace the load-bearing capabilities of the factory-installed circumferential former, so why would it need to be located exactly at STA 307 when it's just stiffening a window patch and not carrying structural loads?

Your guess is as good as mine.  I wonder if the vertical stiffener was added later to counter the "oil canning" we see in the Darwin refueling photo.

[Martin X. Moleski, SJ]

If I recall correctly, the early construction photos of Amelia with the plane show no window here, just the navigator's window.  You mentioned it being added later.  Does anyone know when or why this extra window was added to her plane?  I'm sorry I can't remember anything about it.

From "Windows Come and Go":

"As delivered in July 1936, the airplane had only two windows in the cabin. These were the aftmost standard airline windows and were directly opposite each other. Then in January of 1937 a window was installed in the cabin door on the port side and a larger-than-standard window was installed on the starboard side. This last window is the one that was later skinned over in Miami."^[5]

[Diane James]

@ Jeff

Thank you for those clarifications. 

Jeff, I sense that you are aware that your data rains on an otherwise exciting parade. I view your report on 2-2-V-1 as the product a serious researcher seeking replicable facts.  The facts are the facts, and the consequences of those facts fall where they may.

As a newbie, even though I have been a lurker I am free of any prior politics regarding 2-2-V-1, and I certainly don't think you are in any sort of opposing camp just because you discovered data that doesn't fit. TIGHAR has an object that seems in very many ways to fit the patch installed at Miami, and you have measurement data that says it seems too big to fit. That makes you a researcher not a critic. 

You wrote: "Another oddity of the '307 feature' is the lack of fastener holes there - why bother re-installing that missing segment of the 307 ring former only to allow it to simply lie in contact without benefit of stiffening / strengthening fasteners? "

And that is my point. Some structural engineer (we hope!) at some point determined that the Electra could be safely flown with a navigator's window sized piece cut out of its fuselage on the right side.  That included cutting and removing a fair-sized piece of the circumferential ring former at STA 307. The airplane proceeded to successfully fly in that condition.

When the transparent window was replaced in Miami there would have been no need to repair the previously cut former. To properly repair the former would have required the scrap that was removed when the opening was cut, or a similar section from a salvaged or factory new part. None of those were likely to have been quickly available to whoever created the patch in Miami. Other than speculation that a repaired former might have underlain the vertical feature on the patch, I haven't seen any indication that the former was repaired.

While it was logical to initially think the prior location of the fuselage former would be where a vertical reinforcement would be located on the patch by the person fabricating it, there is really no structural reason to have located it there.  He was only reinforcing a window, not repairing structure. 

How do the artifact's measurements work if the forward edge is aligned as photos show the patch to have been?  If it's moved that far aft, without reference to the vertical or the tear, does it then fit?