Originally posted by oboe:
Does anybody have a good method of establishing turn performance numbers for AH aircraft?
You can use the minimum turn radius "index number" method. To use this method, you need to know the following:
Gross Weight.
Wing Area in Square Feet.
Maximum Lift Coefficient.
Finding or determining the lift coefficient will be your biggest challenge.
Here's how it works:
Gross weight/wing area/lift coefficient= turn rate index.
Here's the calculation for the P-38L:
Without 8 degrees of Fowler flaps.
17,100/327.5 = 52.21/2.17 = 24.06
With maneuvering flaps deployed:
17,100/369.8 = 46.24/2.73 = 16.93
Let's compare the P-38L to the F4U-1:
11,800/314.0 = 37.58/1.48 = 25.39
The F4U performs so badly due to the spoiler added to the right wing (to cure the wing drop in a stall condition), which kills the lift coefficient.
On the other hand, the big P-38 turns remarkably tight if the pilot sets the flap handle to the 'maneuver' position. By doing so, the P-38 can turn with the Hellcat and run rings around the P-51 and any Luftwaffe fighter. The P-38 pilot could briefly tighten his turn by deploying his dive recovery flaps in the turn, which would pitch up the nose. Amazingly, the huge P-61 Black Widow can turn tighter than all the above with a 16.0 index #.
Finally, lets look at the index # for the A6M5:
6,025/229.3/2.46 = 10.68
Here's some index numbers for some AH aircraft:
F6F-5: 16.52
P-38L: 16.93
P-51D: 21.49
F4U-1D: 25.39
P-47D-30: 24.68
A6M5: 10.68
Others:
FM-2: 11.99
P-63A: 14.87
P-40B: 15.30
So, let's put them in order of turn index:
1) A6M5
2) FM-2
3) P-63A
4) P-40B
5) P-61B
6) F6F-5
7) P-38L
8) P-51D
9) P-47D
10) F4U-1D
If you locate the Lift Coefficients of the other aircraft in AH, you can calculate their turn index relative to each other.
My regards,
Widewing