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[Mark Pearce]

Jeff,
I took a closer look at that web page devoted to the B-17G wreck in the Olympic Mountains, Washington.  One photo of the right wing shows very good detail of the skin and rivets.   In the lower/center of the image you can see that the heads of four adjacent rivets have popped off.  Judging from the shank to head diameter, would you say these rivets are AN455 braziers?  [...size is another matter of course, and tough to nail down from the photo alone, yet it appears many of these rivets are on the small side...  maybe even -AN3s?]

What do you think?

I remember you tackled this question before;

https://tighar.org/smf/index.php/topic,1426.msg30106.html#msg30106
"...Even a good visual of shank vs. head tells us something: a brazier head is distincly more than 2x the shank in diameter, while the 'modified brazier' head is less than 2x the shank - very apparent.  Look at the actual artifact rivet in the photo - the head is rather flat, but still has the dimple of an "AD" rivet in evidence so it was not severely worn flat but is close to its original shape and dimension: a 'brazier' does have a relatively flat head (bigger radius) compared to the more sharply radiused 'modified brazier'.  More telling is the head diameter in the artifact rivet compared to the shank diameter: head diameter is clearly in excess of 2x the shank diameter.

The artifact rivet is clearly a 'brazier' #3, not a 'modified brazier'.
 
[Click hyper-link and then the image for a blow-up view.]   

http://746project.files.wordpress.com/2012/11/dsc02002.jpg

[Ric Gillespie]

Canton was on the southern ferry route for Hawaii to australia... that has to be almost every long range plane used in the pacific theater??

That's right, and not just long range planes.  There were few single engine aircraft shipped to Canton. P-39s, A-24s (Army version of the SBD Dauntless and, if recall correctly, a few P-40s.

[Kevin Weeks]

Canton was on the southern ferry route for Hawaii to australia... that has to be almost every long range plane used in the pacific theater??

That's right, and not just long range planes.  There were few single engine aircraft shipped to Canton. P-39s, A-24s (Army version of the SBD Dauntless and, if recall correctly, a few P-40s.

I did read that P-39's were actually stationed there...  didn't see much else for fighters in my search.. nor anything bigger than the B24/b17.... no b29's. doesnt mean there werent any.. I just haven't come across a Navy list saying "For Future Tighar reference, here is the list of planes that went through Canton airfield" lol


this question will open up a whole can of worms but I have read that many japanese variants used alclad. Specifically the A6M5 Zero was skinned in .032 alclad.... considering this material was a fairly new American invention is it fair to consider that the japanese may have used american type rivets as well??

I have yet to read anything about Japanese aircraft going down in the vicinity just curious as to your thoughts on this??

[Ric Gillespie]

I did read that P-39's were actually stationed there...  didn't see much else for fighters in my search.. nor anything bigger than the B24/b17.... no b29's. doesnt mean there werent any..

Canton was a refueling stop for aircraft en route to the Southwest Pacific Theater.  B-29s were used late in the war to bomb Japan from bases in the Marianas.  Look at a map. There would be no reason to send B-29s through Canton.

I have yet to read anything about Japanese aircraft going down in the vicinity just curious as to your thoughts on this??

I think that trying to make 2-2-V-1 part of a Japanese aircraft requires so much assumption and fanciful speculation that it's a total waste of time.

[JNev]

Jeff,
I took a closer look at that web page devoted to the B-17G wreck in the Olympic Mountains, Washington.  One photo of the right wing shows very good detail of the skin and rivets.   In the lower/center of the image you can see that the heads of four adjacent rivets have popped off.  Judging from the shank to head diameter, would you say these rivets are AN455 braziers?  [...size is another matter of course, and tough to nail down from the photo alone, yet it appears many of these rivets are on the small side...  maybe even -AN3s?]

What do you think?

I remember you tackled this question before;

https://tighar.org/smf/index.php/topic,1426.msg30106.html#msg30106
"...Even a good visual of shank vs. head tells us something: a brazier head is distincly more than 2x the shank in diameter, while the 'modified brazier' head is less than 2x the shank - very apparent.  Look at the actual artifact rivet in the photo - the head is rather flat, but still has the dimple of an "AD" rivet in evidence so it was not severely worn flat but is close to its original shape and dimension: a 'brazier' does have a relatively flat head (bigger radius) compared to the more sharply radiused 'modified brazier'.  More telling is the head diameter in the artifact rivet compared to the shank diameter: head diameter is clearly in excess of 2x the shank diameter.

The artifact rivet is clearly a 'brazier' #3, not a 'modified brazier'.
 
[Click hyper-link and then the image for a blow-up view.]   

http://746project.files.wordpress.com/2012/11/dsc02002.jpg

Thanks, Mark - good find.

Yes, by head : shank diameter ratio those appear to be AN455 braziers to me, as the data on the B-17 indicates for some wing panels (this would be an outboard panel apparently).  They are also "AD" rivets, so good candidate consideration there as well.

You are right about judging size, but given the 'typical arrangement' one might expect, there appears to be a variety including #3, #4 and #5 braziers on the visible surface.  It is possible that they are all a size larger - #4 - #6, but #6 (3/16" diameter) rivets are not so common in a skin installation like this, even at the beam.  My best guess, short of having true scale, is that the rivets with missing heads are #3 in size, and by their footprint are braziers.

The parallel rows where the outer skin adjoins the corrugated panel beneath of course make a very interesting pattern as well, close to what we see in 2-2-V-1.  In fact, we see what may well be #3 rivets (no true scale, best guess) lying in rows that parallel a neat row of what may be #5 braziers.  This of course is exactly what we've been talking about having a closer look at, question being whether we can find a good match.  As best I can tell, the row spacing is probably too fine (too close together) to match 2-2-V-1, but of course we're only seeing a portion of the wing (and we have no scale to be certain).

This is certainly a good example of why we need to look at the B-17.  What examples might you find of the B-24?

As an aside, the corrugated underskin on the B-17 is an impressive feature - coupled to the outer skin as we see here, it was in some ways similar to honeycomb construction that emerged later in terms of rigidity and strength with light weight.  No doubt it gave a measure of structural redundancy that was important for surviving battle damage.

Thanks!

[Kevin Weeks]

Canton was a refueling stop for aircraft en route to the Southwest Pacific Theater.  B-29s were used late in the war to bomb Japan from bases in the Marianas.  Look at a map. There would be no reason to send B-29s through Canton.

I have yet to read anything about Japanese aircraft going down in the vicinity just curious as to your thoughts on this??

I think that trying to make 2-2-V-1 part of a Japanese aircraft requires so much assumption and fanciful speculation that it's a total waste of time.

The southern route #1 that included canton was not active for very long. route #2 was created fairly soon that bypassed Canton.

I wasn't inferring that 2-2-V-1 should be considered japanese.... there were no japanese aircraft lost anywhere remotely close to gardner that I know of. this post was just picking your brain. I have not seen a wwii japanese  aircraft in person. I thought that at one point we were considering the alclad material "strategic" where it would not be available to the japanese. Now we see that it was available to them. obviously it is harder to find japanese technical data... just pondering the rivets since you called them "american"

the a6m5 I gave as and earlier example made from .032 alclad used flush mount rivets btw...

[Jeff Carter]

Off topic.  Having seen the Mavis Alclad picture, Japanese aircraft aluminum was more often stamped with SDCH
http://www.pacificwrecks.com/resources/aircraft/sdch/index.html

Germans had their own version, but I can't make out the exact letters:
http://www.asisbiz.com/il2/Fw-190D/Fw-190D-JG54.10-Black-12-Nibel/pages/Focke-Wulf-Fw-190D9-10.JG54-Black-12-Theo-Nibel-Bodenplatte-1945-01.html

[Monty Fowler]

I think that trying to make 2-2-V-1 part of a Japanese aircraft requires so much assumption and fanciful speculation that it's a total waste of time.

I agree with that; TIGHAR has a little field trip planned to weed out the likely USAAF candidates; and detractors can argue that aliens put it there all they want. Because they will. but this one's going to be game, set and match for TIGHAR.

LTM, who never understood tennis,
Monty Fowler, TIGHAR No. 2189 CER

[Kevin Weeks]

I think that trying to make 2-2-V-1 part of a Japanese aircraft requires so much assumption and fanciful speculation that it's a total waste of time.

I agree with that; TIGHAR has a little field trip planned to weed out the likely USAAF candidates; and detractors can argue that aliens put it there all they want. Because they will. but this one's going to be game, set and match for TIGHAR.

LTM, who never understood tennis,
Monty Fowler, TIGHAR No. 2189 CER

And given the number of planes/rivets to check there that will be one heck of a job!

[Jerry Germann]

http://commons.wikimedia.org/wiki/File:Joe_Cobb,_former_%22fat_boy%22_in_the_original_%22Our_Gang%22_comedies,_now_helps_build_B-25_bombers_at_the_Inglewood..._-_NARA_-_195480.jpg

alclad labeling shown in this image ( war time) displays a somewhat wave action pattern...mis-alignment with the grain of the metal

[Mark Pearce]

I think that trying to make 2-2-V-1 part of a Japanese aircraft requires so much assumption and fanciful speculation that it's a total waste of time.

I agree with that; TIGHAR has a little field trip planned to weed out the likely USAAF candidates; and detractors can argue that aliens put it there all they want. Because they will. but this one's going to be game, set and match for TIGHAR.

LTM, who never understood tennis,
Monty Fowler, TIGHAR No. 2189 CER

Monty, now you can go knowing a B-17 crashed on Canton Island.  You had doubts about it earlier.  I thought it was at least possible.

http://tighar.org/smf/index.php/topic,1426.msg30305.html#msg30305

[Ric Gillespie]

.mis-alignment with the grain of the metal

Looks like classic rolled-on with the grain labeling to me.

[Doug Ledlie]

The rows of rivets appear to taper but does that necessarily mean the underlying structure had to taper, given a poorly aligned rivet job?

Applied an over lay showing one possible fit for 1" parallel stringers on 4" or 4.25" centers.

[Mark Pearce]

.mis-alignment with the grain of the metal

Looks like classic rolled-on with the grain labeling to me.

These two fonts look very similar.  The people at Vultures Row Aviation might know a lot about Alcoa ink stamps and when they came into use.  It seems there were different styles. 

http://www.vulturesrowaviation.com/helldiver10_2010.html

"...Attention to detail is mandatory and truth be told it's an obsession. Shown here is the detail in our ink stamp markings on aluminum skins and the pitot tube lines."
 

[Ric Gillespie]

These two fonts look very similar.

Not to me. The D on Helldiver has "serifs." The D on the artifact does not.