Ki-84, "Macho blue yonder" and P-51-'38-'47 killer or just another stop gap fighter?

[gwshaw]

HoHun,

Are you adding the 150 lbs exhaust thrust?

Without it I get 422 mph @ 23,000 ft.

These are the complete figures I am using:

wgt - 7955 lbs
wingspan - 36.87 ft
wing area - 226 ft^2
aspect ratio - 6.015
Cd 0 - .0210
atm density ratio - .4806
e - .85
P% - .8
hp - 1577

calculated figures

dynamic press - 219.8205 lb ft^2
Cl - 0.1598
Cd - .0226
Cd 0 drag - 1043.3 lbs
total drag - 1122.3 lbs
thrust - 1121.3 lbs

(that is about a 3 fpm sink rate, reposted to correct mixed condition figures I used originally)

It would be interesting to see where we are differing.

Greg Shaw

[HoHun]

Hi Greg,

>Are you adding the 150 lbs exhaust thrust?

I'm merely adding 71 lbs because I figure a collector exhaust still gives about 50% of the full thrust.

>It would be interesting to see where we are differing.

The thrust probably our biggest difference :-)

We also differ greatly in our method - I'm using a spreadsheet approximating quite a lot of input variables, which has some advantages as well as some disadvantages.

The important thing at the moment is that despite using completely different methods, we arrive at very similar results :-)

Is the altitude known at which the famous 427 mph were achieved? I didn't follow the thread above closely.

Regards,

Henning (HoHun)

[Karnak]

I don't know the altitude that was at, but I would imagine it was at the full blower altitude of the second stage of the super charger.  Looks like 6,400m by Wotan's data.