Nakajima AT-2 (Ki-34) airfoil

[karoisan]

Hi!
Does anyone have any information on the subject?
I read that the design was heavily influenced by the DC-2, which has NACA 2215/NACA 2209 (root/tip).
I found a picture showing the AT-2 airfoil, but I'm not sure if it's the same as the DC-2.

 

[Shinpachi]

Japanese local Wikipedia tells that the Nakajima AT-2's inner wing was same as DC-2 but outer wing adopted Northrop 2E's to avoid lawsuit with Douglas. No more details are available at the moment.

 

[Graeme]

One of the sources on the Wiki site is Wilson (Aerospace Publications-1999) and reproduced here. Certainly a much smaller aircraft compared to the DC-2.

 

[karoisan]

Many thanks!

 

[Aeroweanie]

Guessing that the image is taken about 30 off centerline, the airfoil t/c works out to about 15%. I'd guess that this is the NACA 2215 airfoil.

 

[karoisan]

Thanks a lot Aeroweanie! Yes, it is probably indeed NACA 2215. I found another picture which is part of a newspaper article about the Nakajima factory in 1940. It shows the assembly of the AT-2s. You can also see a wing profile in the bottom centre of this one, though not in very good quality. It also looks like a NACA 2215.
Taking Shinpachi's information into account, the wingtip on the AT-2 may have been NACA 2409, the same as on the Northrop Gamma 2E.
By the way, a book about AT-2 was published in Japan, which is now very rare to find even in antiquarian bookshops and archives. I would be very curious to read it...

 

[Shinpachi]

By the way, a book about AT-2 was published in Japan, which is now very rare to find even in antiquarian bookshops and archives. I would be very curious to read it...

AT-2 airfoil: NACA2213/2208

Source: internet

 

[Aeroweanie]

AT-2 airfoil: NACA2213/2208

View attachment 673607
Source: internet

Excellent - I have it in the database. Now, I need to update the Incomplete Guide to Airfoil Usage. Its very overdue.

 

[karoisan]

Wow! Thanks a lot Shinpachi!