IJAAF fighter gun convergence

[greybeard]

Hi all!

I was unable so far to find anything about gun harmonization figures in use for Army fighters. I wonder if someone has and can post here relevant data. Any kind of fighter/weapon would be welcomed.

Cheers,
GB

 

[Tracker]

GB,
Info has been posted under another thread.
http://www.ww2aircraft.net/forum/ot...al-200-1-fighter-gun-harmonization-20658.html
Hope this helps.

 

[greybeard]

Thank you Tracker, but there's a misunderstanding! Sorry, my fault: I should have better describe that I was speaking of Imperial JAPANESE Army Air Force!

Indeed, there's an almost total lack of this kind of info about Japan Army fighters (found some partial and unconfirmed data about Japan Navy fighters, thank to a Japanese friend, time ago), easily explained by destruction of original documents at war end.

It is quite easy to get American figures (Army, Navy, USMC) by plenty of dedicated manuals (like that you pointed out), aircraft manuals and so on. Also enough available similar material for Luftwaffe. Oddly, I was unable to find anything also about RAF fighters: apart a hint somewhere by Tony Williams, no official documents look still declassified!

Cheers,
GB


BTW, would be really GREAT if on this forum an user wouldn't automatically logged out every ten seconds or such; being English not my language, I spend a while to compose a message, during which I'm forced to login over and over...

 

[Tracker]

GB,
Understood. Will be on the look out for Japanese info for you.

 

[Shinpachi]

I heard the gun harmonization for IJA fighters was controlled by electric contacts.
It was so simple that fighter operation manuals did not explain more details.

 

[greybeard]

Thank you Shinpachi!

But where they converged? 200 m, 300 m or what?

 

[Shinpachi]

Sorry greybeard. I misunderstood your question.
The convergence was officially 200m in the navy but 400m was recommended for the 20mm cannon as ballistic was unstable.
Unknown about the army at the moment.

 

[greybeard]

Thanks Shinpachi!

Indeed, I got similar values for Navy time ago from a Japanese friend.

He was unable to find any info about Army. If you succeed, would be great!

Moshimoshi,
GB

 

[Shinpachi]

Convergence for the army fighters would be 300m as firing tests were taken place at 300m.
Mechanic of World Aircraft says the convergence was between 250m and 300m for the army Ki-84.

 

[greybeard]

Convergence for the army fighters would be 300m as firing tests were taken place at 300m.

This is a fundamental info, although not quite definitive, since at 300 m they could still have a bore sighting chart, like in following example:

where it is set at 1000 inches = 25 m. Looks to me unlikely, though, that they placed a bore sighting chart so far; probaly, it was a simple target face where to converge.

Mechanic of World Aircraft says the convergence was between 250m and 300m for the army Ki-84.

Actually, I was expecting the value 250 for Ho-103, since using same round of Italian Breda-SAFAT 12.7 mm - and Italian had their San Giorgio gun sight made to hit at 250 m.

I guess "Mechanic of World Aircraft" are meant as "armorers (or simply ground crews) of WWII".

At any rate, hints you kindly provided at least point out that IJAAF fighters had their convergence set to the values most common to the coeval fighters.

Arigato,
GB