Kawasaki Ki 61 with Merlin or other engine?

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

Admiral Beez

Captain
8,576
9,646
Oct 21, 2019
Toronto, Canada
Was the Ki-61 ever tried, maybe post-war with other inline engines, like the Merlin, Hispano-Suiza 12Y or Allison? Postwar the Italians put Merlins in their G.55s and called them G.59s.
 
Much like real estate, the importance of location, location, location cannot be under estimated.

Why go to the trouble and expense of bringing a Japanese Warbird to the US or Europe when surplus American, British and ex axis fighters were sitting on runways or just off them, either to be had for scrap or being sold surplus for pennies on the dollar?
In the US some planes were sold for less than the value of the fuel in the tanks. Some of these planes were purchased and owned (at least for a short while) by ex pilots.
Buying a plane for 500-1000 US dollars in the US was one thing. Trying to get a Japanese plane from a Pacific Island is going to cost a lot of money (comparatively) and spare parts are going to be a real problem.

You still needed some sort of airworthiness certificate to fly these aircraft, doing engine swaps would require a lot more paper work.

Interest in museum pieces and diversity of hobby warbirds may have come too late.

The Economy of Europe was in the tank for a number of years after the war and some countries were hustling for all the foreign currency they could get.

Czechoslovakia cobbled together 109 Airframes and Jumo 211 engines because they ran out of DB 605s. Sold some to Israel.

By the time the Italians were building Fiat G-59s they were either for Argentina or Syria or the Italian Air Force as trainers.

Merlins were two speed single stage engines.

Interesting what if?

Italy and Spain go to war around 1950(?) both using piston engine fighters using Merlin engines :)
 
With the low cost of US surplus planes, why would a veteran buy a plane from a recent enemy country if one could find someone who could legally sell it? A friend who had flown F4Us & F6Fs wanted something he could afford. He and a buddy would take the bus to pensacola and buy a couple of N2S trainers for $50 each and fly back to New Orleans. The CAA would not certify a Stearman with out new spars. They could only fly them for limited time on temp permit before the mod or grounding. Therefore all over the country PT-17s & N2S were flown until the CAA caught up and they were left abandoned on airports. For Herb and his buddy, It meant a bus ride back to Pensacola for a couple more Stearmans.
 
I was thinking maybe a captured example might see a Merlin swap? If only as a thought experiment.

4eb8bd74d0e9ee604f7ddb120a5e11b3.jpg

4161f9175bb2da30d1bdef5efe94e9f--swallow-christian.jpg
 
Last edited:
Budgets had seen large cut backs. Existing contracts were being canceled, Jets were being developed as fast as possible.
Spending money/labor on putting different engines in obsolete airframes was not going to be high on the priority list.
In 1945/46 North American for instance was figuring out how to put a swept wing on the F-86 Sabre jet.
Trying to stick a Merlin in a 1941 airframe wasn't going to tell anybody much.
 
I was thinking maybe a captured example might see a Merlin swap? If only as a thought experiment.

View attachment 628967
View attachment 628968
That would entail a full engine mount, fitting, connection, wiring and cowling re-design. Seems REALLY unlikely just for curiosity.
But damn, if that isn't a good-lookin' machine
 
The KI 61 used a modified version of the HE 100 engine mount where parts of the cowling are the engine mount.


KI 61 would be even harder to swap engines to another make than just about any other airplane.
 
A DB601E probably would have fit, I assume. The Hein could have been a solid 400mph machine with that fitment, and would have been a serious adversary when it made its combat debut over New Guinea
 
I have put this out in here before, but here goes again. When I was working for Joe Yancey, we had a visit from retired General John R. Alison. He had some interesting stories to tell of his P-40 days (another post maybe) , but also mentioned the Ki-61.

Seems like a friend of his who was both a pilot and a mechanic flew a capture Ki-61 and had an engine issue after some 2 - 3 hours of flight. Being a mechanic as well as a pilot, he apparently removed and disassembled the Ha-140 engine. He found that the oil return line from the nose case back to the crankcase had not been drilled. So, the engine would start normally and run from some time, but would eventually fill up the nose case and have issues. This has not been confirmed by another source as far as I know, but it goes a LONG way toward explaining the observed behavior of the Ha-140, which would start and run fine for awhile and them result in an emergency landing on MANY occasions.

I am thinking that fitting a Ki-61 with a DB 605 would result in a very nice airplane, and fitting one with a reliable engine, even if not a DB derivative, would go a LONG way toward making the Ki-61 a much more formidable opponent. The Ki-100 would seem to prove that easily.

You could fit it with a Merlin, and it would have been a decent airplane. But that would require some serious design and modification that would not pay any dividends because the neither the U.S.A. nor any other country was going to adopt the Ki-61 for their Air Force after the war. So, the main questions for such modification would be, "Why waste the effort?" and "What would you hope to gain that our own airplanes already developed and with better performance to boot can't answer?"
 
Gentlemen

We have the calculated TAIC data for the Tony 2. That shows potentially what the airframe could do with a more powerful engine. The calculations are based on the use of the Ha-140 which I believe is based on the DB-605. Perhaps one could guess from that what type of performance a Merlin powered Ki-61 would have.

I agree with all that has been said before, with jets on the horizon, and shrinking military budgets, any research on an uprated Tony would be way down the list of military research priorities.

I have attached TAIC data for the Tony 2 (and a few other Japanese Aircraft)

FWIW

Eagledad
Eagledad
 

Attachments

  • TAIC Selected Japanese Fighters.pdf
    2.5 MB · Views: 130
I'm not all that sure the TAIC data are useful.

After the war, they had planes to test, Why calculate the performance and how good were the calculations based on comparative flight tests? I've never done a comparison of TAIC calculated versus actual test data myself, but have seen the calculated test data on a few airplanes be a bit off versus the actual quoted flight test data. I'm not too sure it is worth the time to investigate it since primary reference data are difficult at best to come by.

I have seen Bf 110 test data disagreeing with itself by almost 100 mph, and the quoted data for, say, the Ki-61-II, is all ±15 - 20 mph depending on sources. All the TAIC data tells me is they were making a fairly decent guess based on incomplete information, which is what military intelligence does for a living.
 

Users who are viewing this thread

Back