A6M5b "Zero" Diving Speed - 100mph error

[2bighorn]

Originally posted by Soda
Was there any significant structural difference between the two that would account for this?

The biggest difference was in wingspan (over 3 ft), however the profile remained the same.

A6M2 Model 21:
Wingspan, 39 ft. 4 7/16 in.;
length, 29 ft. 8 11/16 in.;
height, 10 ft. 1/16 in.;
wing area, 241.541 sq. ft.;
empty weight, 3,704 lb.;
loaded weight, 5,313 lb.;
maximum weight, 6,164 lb.;
wing loading, 22 lb./sq.ft.;
power loading, 5.5lb./hp;
maximum speed, 331 mph at 14,950 ft.;
cruising speed, 207 mph;
climb to 19,685 ft., 7 min. 27 sec.;
service ceiling, 32,810 ft.;
normal range, 1,160 st. miles;
maximum range, 1,930 st. miles.

A6M5 Model 52: - same airframe as A6M5 model 52 b
Wingspan, 36 ft. 1 1/16 in.;
length, 29 ft. 11 7/32 in.;
height, 11 ft. 6 5/32 in.;
wing area, 229.27 sq. ft.;
empty weight, 4,136 lb.; ***
loaded weight, 6,025 lb.;***
wing loading, 26.3 lb./sq. ft.;
power loading, 5.3 lb./hp;
maximum speed, 351 mph at 19,685 ft.;
cruising speed, 230 mph.;
climb to 19,685 ft., 7 min. 1 sec.;
service ceiling, 38,520 ft.;
maximum range, 1,194 st. miles.

***  (A6M5b was slightly heavier, due to added armor protection and different armament - 125 rounds instead of 100 per cannon, one 7.7mm type 2 MG replaced with 13.2mm type 3 MG, armored windshield, etc)

[Soda]

Originally posted by Angus
TAS or IAS, the a6m in AH can dive too fast, and can recover from an incredibly fast dive. It also rolls too well at high speed (should be almost stuck at 250 mph, and impossible to roll at 350).
Guess they'll have to look into it.

My point was, you should try both Zero models and note the differences.  I always thought the 5b was more accurate as it does suffer serious speed related handling issues.  The 2 just seemed too good in a dive, they were just so different when I tested them.  I used the film recorder in some cases to watch for handling problems so had exact speeds (TAS) for issues like roll rate (basically I rolled in a dive until it stopped and noted the speed).