AerialTorpedoDude69
Airman 1st Class
- 159
- Mar 1, 2022
Greg just published a video on the Nakajima Ki-84 "Frank" Hayate fighter. It's a solid summary of the history, development, and controversy on its top speed.
EDIT:
Much of the information in the video is covered in this thread on the Homare engine.
Some highlights of the video:
There's a part II of this video coming out soon as well as a part III. However, Greg is ill at the moment, so this might be delayed. Best wishes to Greg and hope he gets well soon!
Now there's a part III! Greg goes into the Ki-84's top speed controversy.
Finally, there's the conclusion
EDIT 2: Added part II. It's a wild ride. Greg's video mostly covers the armor plate behind the pilot, which was something like 12.4mm thick and used Ni-Cr-Mo hardening, making it more effective than the plate used in the Oscar. Overall, it's a great update although it doesn't cover some of the performance questions that we've had.
EDIT3: Added part III.
EDIT4: Added the conclusion to Greg's work on the Hayate.
EDIT:
Much of the information in the video is covered in this thread on the Homare engine.
Some highlights of the video:
- The Homare was the only major engine of WW2 that used high RPM and compression ratio to achieve its high horse power rating. According to Greg, the only other engine to use high RPMs, rather than manifold pressure, was the Napier Sabre.
- Japanese aircraft used very few electrically powered components , although had a lot of wiring in them, possibly because they intended to use wooden construction at some point.
- Greg seems to agree that the 427 MPH number for the top speed of the Frank is accurate.
- Japanese water-methanol systems are not well understood, but it seems likely that the Frank's system used 50% water, mixed with 25% ethanol and 25% methanol in order to achieve optimal cylinder head temperatures.
- The system was designed to automatically kick in at around 37-inches of manifold pressure; that's well below the maximum manifold pressure of the Homare.
- Greg thinks that the Frank's oil cooler seems like it was stapled on as an afterthought, although IMO, it seems to be a Meredith effect type radiator
There's a part II of this video coming out soon as well as a part III. However, Greg is ill at the moment, so this might be delayed. Best wishes to Greg and hope he gets well soon!
Now there's a part III! Greg goes into the Ki-84's top speed controversy.
Finally, there's the conclusion
EDIT 2: Added part II. It's a wild ride. Greg's video mostly covers the armor plate behind the pilot, which was something like 12.4mm thick and used Ni-Cr-Mo hardening, making it more effective than the plate used in the Oscar. Overall, it's a great update although it doesn't cover some of the performance questions that we've had.
EDIT3: Added part III.
EDIT4: Added the conclusion to Greg's work on the Hayate.
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