Ha25, 12D40 Question?

[43-2195]

I've been reading some of the topics regarding props on WIX and it has been very informative and helpful, bdk really seems to have a handle on it all. I have a query I hope you guys can assist me with. The Nakajima Ki-43-I utilised a 950hp Ha 25 engine with a two bladed metal prop. From wreck sites that I have visited in PNG and photos taken at the time, the prop hub on these props appears to be an exact copy of the 12D40. I guess we would have to inspect the spline to confirm that. What I would like to ask is; I believe the 12D40 in the USA was fitted to the PW 1340 which I expect was around 600 or 700 hp. Whereas the Ha25 was 925hp. Does the hp of the engine affect whether the 12D40 can be used or not? Are there any hp limitations on it? If the spline fits and we can match the original blade dimensions, is there any reason why a 12D40 could not be fitted to a 925hp engine? Please check ou the photo at the address given below to compare Ki-43-I prop hubs to the Hamilton Standard 12D40.

www.pacificwrecks.com/aircraft/ki-43/nu ... e-wide.jpg

[Dan K]

Sorry, I don't have an answer to your horsepower question.

But several sources indicate Sumimoto license-built 2-bladed Ham-Standard propellors for the Ki-43-I.

Unfortunately I'm not finding the exact model prop. But if not the 12D40, what would it be? Some experts must surely be out there.

[43-2195]

Thanks Dan, I'm still new to the site and haven't mastered the photobucket thing yet. So I cant put any of my Ha25 pics up. But if you check out the pic on Justin's Pacific wrecks site. It looks exactly like a 12D40, but I don't think I've come across a U.S. application of this prop with anything greater than about 700hp. So it's got me wondering about the limitations....if there are any. Judging by WIX member bdk's input to other prop topics, I would think he might have an answer.