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[JNev]

Jeff,

The best rivet detail I found in the Purdue collection for your aft region of interest was in this
port side shot (first-world-flight configuration).

Chuck

Chuck, this is outstanding - thanks!

My belief without more information is that the starboard and port skins and bracing should essentially be symetrical in this section of the fuselage.  This should provide an excellent starting point to compare rivet size and pitch along the visible fastener lines.  Excellent - many thanks!

LTM -

[JNev]

Here is a 'paint' illustration of the close-up of the covered window to illustrate the area I've been describing (lavatory starboard skin).  It is based on the photo that shows the cover panel - which is now a bit obscured by my 'crayon' work, but I wanted to lay out the idea of how the artifact might fit.

Note the size of the window covering - approximately 20" high by 26" wide (as best I can scale it from the fuselage stations (given in inches) and from the photo).  The artifact is smaller than the opening.  Since 2-2-V-1 is a smaller piece than whatever it was originally a part of, a fit here within the bounds of this panel is not out of the question.

[Chuck Varney]

Jeff, there's a lot of stills on this link that show the inside of the Electra viewed from outside the fuselage door. You can see the FN's navigation window and, where the other original window should be but isn't. Looks like these images were aquired after the skinning over.

Jeff V. H.,

The video clip and stills in your link show the aircraft prior to departure for Hawaii in March 1937. The starboard window configuration at that time was as shown in this link, posted earlier in this thread by Ricker Jones.

Chuck

[richie conroy]

the reason i suggested the tail section is because there appears to be large sections with just rows of rivets

here is some images for you to look over hope they help 

[richie conroy]

more pic's

[richie conroy]

has anyone checked this area out

[richie conroy]

here is side view

[Ricker H Jones]

See the Ameliapedia for other previous work done on 2-2-V-1 HERE and HERE.

[JNev]

Thanks Ricker!  There is quite a bit of information on this item at TIGHAR - well worth reviewing all of it.

Here is one more sketch based on a reversed image of the photo Chuck came up with (detail of left side ('port') aft of door.  So far I am getting 1.5" rivet spacing in each row of the 'double row' (as shown) and about 1.25" vertical rivet line spacing - based on measurements from the known stations / distances in the picture.

[Tom Swearengen]

Jeff---recall us looking at this in person ALOT---remember talking about the contour of the roll on the panel? Looking at the pics posted here, I think the shape is wrong. For it to fit on the aft window, the rivit lines we saw would have to be vertical, which is ok, but the contour to fit from the side of the fuselege towards the top need to have a slight roll in the vertical direction with the rivit line. The piece we saw in DC was opposite; the roll was perpendicular to the rivit line.
NOW---- thats not to say that it didnt come from the Electra, or from the window patch repair. Being it was found in the village, it 'could' have been altered. The length and width appear to be correct, but the contour bothers me.
Maybe we should make a run to Pensecola to look at the Electra there, and see if we can figure this out.

[Tom Swearengen]

UPDATE: Jeff  the rivit lines in the artifact more closely resemble the wing walk area of the wing root. The contour is still off, but we're getting closer. I dont think its from a fuselege side panel ; not enough rivit lines.
Tom

[JNev]

...the rivit lines we saw would have to be vertical,

I don't think so -

...the contour to fit from the side of the fuselege towards the top need to have a slight roll in the vertical direction with the rivit line.  The piece we saw in DC was opposite; the roll was perpendicular to the rivit line.

Look again - see what the NTSB report says about 2-2-V-1.

In part, as you look at the photos of 2-2-V-1 in the NTSB report, consider the 'convex' view - it places the larger diameter, outer edge row of fasteners at the top - with the 'stiffener' rows (if that's what they are) tapering from narrow at left to wider at right: this could be a good fit for the fuselage in that area (the large rivet holes don't match the pitch of the lower window edge: 1.25" vs. 1.5" pitch). 

Also, while the window appears to have been very close to a true rectangle, the fuselage taper in that area does not follow that pattern: look at the pix - the upper window edge departs the natural tapering 'waterline' slightly.  It is the tapering nature of that section of the fuselage that suggests the taper we see in the stiffener lines.

NOW---- thats not to say that it didnt come from the Electra, or from the window patch repair.

Good candidate I believe - still looking at that and far from exhausting the possibility. 

The wing-walk area is intriguing - possible; but I am holding with the window cover panel for now until I can exhaust that - the key may be the stiffener pattern and whether we can get a view of that 'patch' with enough resolution to see if any were present, what the line layout was, etc.  Edge fasteners are also important - but the one surviving edge we see does not match the known pitch of the fasteners along that double-row at the lower water line of the window (artifact edge rivets pitch = 1.25", NR16020 rivet pitch along that water line appear to be more like 1.5", if I'm getting it right from the stations and rivet count).

Of course this thing could still have come from any number of other airplanes somehow.  No definite match to the Electra, no dice.

Being it was found in the village, it 'could' have been altered.

It well could have been - but not likely in an 'aircraft' kind of way, i.e. rivet holes added in uniform pattern, etc.

Bending?  Easily.  Despite what we may each think of the 'contours'.  For one thing you have to be careful about trusting the 'contour' anyway - this thing's been mauled pretty badly, and we don't know what from.  It could have been hacked and peeled away from whatever the parent structure was by someone who wanted it for salvage - and that includes 're-making' the contour in any number of ways.  The NTSB report does note that it was bent about 90 degrees at one place; there could have been alot of different angular forces working against it.  Some force appears to have been exerted in a hydraulic fashion against the panel to press it outwards from its fasteners by what I am reading in the NTSB report, so that 'contouring' is evident too.

The length and width appear to be correct, but the contour bothers me.
Maybe we should make a run to Pensecola to look at the Electra there, and see if we can figure this out.

Back to the NTSB report and what I've said above - and considering that we may not be seeing a normal contour. 

Actually - when you consider the NTSB report and what I recall of the artifact when we saw it, the stiffener lines to seem normal to the 'flat' span and the curve is natural (rolling perpendicular to the 'stiffener' lines, i.e. stiffeners would lie 'straight' more or less (fore and aft), but skin would 'roll' as it progressed vertically.  We may recall it differently, so not to say I'm right - but I'm looking carefully at the pictures I took while there and trying to recall nuance as best I can.  The NTSB report is helpful in interpreting what I saw.

Pensacola - eventually may do that if we can get the right door open to get close (I don't think the Museum of Naval Aviation will let us crawl all over their Electra without some arrangement...), that is if we don't have something better to compare it to after July (long shot, but hey...).

Interesting, huh? 

LTM -

[JNev]

UPDATE: Jeff  the rivit lines in the artifact more closely resemble the wing walk area of the wing root. The contour is still off, but we're getting closer. I dont think its from a fuselege side panel ; not enough rivit lines.
Tom

Not an original skin panel, that's not what I'm talking about.

You have to keep in mind that the skin cover would not necessarily match anything about the 'stock' airplane except two rows of edge fasteners:
- the horizontal, lower row where it appears to pick-up that existing line of rivets, and
- the vertical row at Sta. 320 where the aft edge of the window panel appears to overlap the frame / existing rivet holes.

Unfortunately, we don't have all the edges, of course... but -

The forward and upper edges don't appear to attach to any existing rivet lines -
- The forward edge appears to butt up immediately behind (faired in) the skin lap at Sta. 307, so that may be (probably is) a unique pattern (by not picking up existing fasteners);
- the upper edge rivet line flies along what was originally an unbraced section of skin - an open area membrane with no internal bracing along that line in the original structure; something had to be added there to accomodate the upper edge of the new window at the time it was put in; the cover would most naturally pick-up that same added fastener line.

The intermediate (mid-panel) 'stiffener' rivet lines - no pattern in original structure:

If the intermediate rivet lines do relate to added stiffeners (I suspect that strongly) their placement would not be so critical - they would not match any existing structure on the airplane because there wasn't any, before the mod or after: this area had a different brace pattern - heavier - before the window was added; once the window was in, it was all, well, 'window'.  After the window was covered, the sole purpose of such stiffeners as I see it would be to stiffen the large, thin metal panel membrane against oil canning and slipstream, vibration, etc. - that's all.  It would act much as a light fairing.

Of course this is all theory - but it makes sense given what we can observe.  It does not make sense in 98 percent of the structure to expect 3/32" rivets to pick-up primary support structure, but they could work well as I have described - and would be effective for the light stiffeners needed to stop a large membrane from vibrating or oil-canning in flight, etc.  This would keep the weight down as well.

Think that over and I think you'll see where I am coming from in this possibility of 2-2-V-1 being a window blank.  I am still a long way from abandoning the possibility of this location, although any possibility is of course welcome.  Likewise, if someone sees a 'fit' on another bird that could be a source, I'd like to know that too: it's 'truth' that I'm after.

LTM -

[JNev]

Studying the rivet patterns on the Electra again and considering the rivet pitch with a better means of scale, I can see two things:
1) The existing vertical rivets are pitched closer to 1.05" apart, not 1.25".
2) That tells us little if anything about the 'artifact' being a 'fit' - there do not appear to be any remaining rivet holes in the artifact that match any existing rivet patterns in this area of the Electra.

That means short of having the Electra 'in hand' in which case the artifact becomes little more than an interesting item that might be shown to have come from it... or -

Matching the artifact to an as-yet-to-be found picture that will reveal any 'field' rivet lines that may be consistent with those on the artifact.

So I need a good picture... but will relax if the wreck is found in July (and not holding breath, but hey...) 

LTM -

[Andrew M McKenna]

Jeff

There has been a lot of work done to try to match this piece to the Electra.  I wish Ric or Jim Thompson could chime in here as they did the lion's share of the effort.

I'm curious what you think of the attempt to match the skin to the roof of the Electra over the cabin door.  This seemed to be the best match we could find, although the air vent scoop seems to discount the possibility.  Maybe with your background you can see a match in a way that we didn't.

 

you can also find in the Ameliapedia other material such as rivet pattern rubbings, and photos of the roof and air scoop from other Electras that we were trying to match

http://tighar.org/wiki/2-2-V-1

Thoughts?

Andrew