August Model Aircraft Monthly: Major Zero variant discovery

[FLYBOYJ]

Originally Posted by proton45

That was my thought...it seems like their would have been anecdotal evidence at the very least (mechanics interviewed and the such). Their are some stories of mechanics cannibalizing aircraft in Rabaul but i never heard mention of any incompatibilities between manufacturers...

Prime manufacturers had problems with interchangeability with their own production lines, here's a story about some of the logistical problems the Japanese had.

Japan’s Fatally Flawed Air Forces in World War II HistoryNet

[FLYBOYJ]

Here's something...

"Both main landing gear legs were completely removed, inspected and repaired where necessary. The left leg of No. 3030 was shot through with a heavy caliber bullet necessitating its replacement from other parts available. Parts were not interchangeable to a high degree, so much hand fitting was required"

Reconstruction of Japanese Type 0 Mk 2 SSF HAP

TAIC Report 163

I remember reading an interview with a former Japanese AAF pilot who spoke about the poor quality of their aircraft along with reliability and interchangeability problems. I'll try to find it.

[Wayne Little]

Well I'll give him points, at least Gaston took it on the chin and apologised for all the hoo ha!...certainly caused quite a frenzy!!

[proton45]

Originally Posted by FLYBOYJ

Prime manufacturers had problems with interchangeability with their own production lines, here's a story about some of the logistical problems the Japanese had.

Japan’s Fatally Flawed Air Forces in World War II HistoryNet

Interesting reading...its a good read on Japanese air planning. Thanks

[Capt. Vick]

...that addresses the incompatability of Japanese aircraft replacement parts...Oh and it also deals with the Arado Ar 196 by way of comparison. enjoy!

Arado 196 in the Pacific

[Gaston]

To help explain what started all this, here are the original profile photos that got the ball rolling...:

http://www.warbirdphotographs.com/Na...63-4_small.jpg

http://www.warbirdphotographs.com/Na...os/Zero-96.jpg

The more critical first photo has a bigger more complete version here:

http://i81.photobucket.com/albums/j2...creprages_.jpg

Measuring various individual items on the larger photo (1/35.5 on my screen), such as the rudder hinge dogleg that is an actual 4.2" (106 mm) in lenght, made the whole aircraft come out at about 8.92 M. vs the quoted 9.06 m. lenght for the "known" Zero.

Seemingly confirming this, by matching precisely the canopy lenghts to scale, front and back, on the two smaller photos, I created a 6-8" shortfall in the Nakajima A6M7 tail versus the Mitsubishi A6M5 at take-off, but NO real mismatch at the front in cowling size/diameter etc...

Also the Hasegawa kit came up at 4" short compared to the new Tamiya, looking better against the big factory photo, and thus egging me on...

Even now, looking at this seemingly very neutral and unperturbed profile photo (better centered by half I think than the added red line would indicate), I do not see a photo severely afflicted by the partial distortion of the "fishbowl" effect... Minor elements seem to scale out roughly to the lenght, but a slightly shorter lenght...

I think there may be something specific about the Zero's shape that maybe conceals variations in angles or distortions: a lack of straight lines anywhere in the rear fuselage body maybe...

I have made seven other profiles visible here, some slightly hurt by conversion from Corel to PDF:

Advanced Air Force Variant

I have since massively improved these drawings, and the "Air Force" boardgame cards and rules, with much new surprising comparative data (E-mail me to get them free at - Gaston1_01@hotmail.com - if you are interested), but even in this old outdated version, you can see all my profiles are quite OK, and better than many others in general outline... The Zero is the only one that really confounded my photo overlaying method, my old Zero drawing seen here being close to the 1/48th Hasegawa kit; 4" shorter than the correct Tamiya, but still looking better against the above big photo than the Tamiya, which fails to overlay it completely... But then the Tamiya does match better the Zero at take-off...

I am now in the position where either the big photo is of a one-off aircraft with a tail prototype (unlikely!), or it does have some selective fishbowl distortion that looks very neutral and discrete, maybe thanks to some of the elements of the Zero's shape...

When, in addition to this, I saw the line-up photo, I felt the differences in parking angles were not in line with the differences in tail appearance, but obviously I was wrong...

I think the seven fairly good profiles I made show that my method of choosing 90° neutral profile photos can yield good results, if the photos are not taken from too close, but obviously in the case of the Zero this failed...

The point I wanted to make is that the "line-up" photo was far from being my only starting point for this whole misguided theory...

Sorry again for the "much ado about little"...

Gaston

[Airframes]

It's a shame that all that work was for nothing, in some ways. But a little advice for future projects - if you're going to measure and analyse photographs, do the initial work from an actual print, or a litho half-tone at least. Trying to obtain even half accurate measurements from a screen is difficult, if not impossible, due to the differences in compression and or distortion, unseen by the human eys, which effect all screens to at least a small degree.

[Airframes]

I wonder if this is the short-tailed or long-tailed example?
Sorry, no offence meant, I just couldn't resist taking this shot at Duxford a couple of weeks back.....