After abandoning the T7 and T7E1, work on the T7 program
continued with the T7E2, T7E3, and T7E4. The T7E2 was selected to utilize the
British QF 6-Pounder Mk. III as its main armament and was powered by a Wright
Whirlwind R-975-EC2 engine. The T7E3 used twin Hercules DRXBS engines that
could put out 123 hp each, and the T7E4 used twin Cadillac engines. The T7E2
was later selected to mount the M4 Sherman’s 75 mm M3 gun, where it became the
T7E5. But at this point, the tank had bloated to a weight of almost 27 tons. At
this point it was redesignated as the M7 medium tank.
The production tank was to use a Continental R-975-C1
engine, or possibly even the Ford GAF. The weight issues were addressed and
some of the armor was thinned, resulting in the M7E2. However, this tank was
even worse than the M4 in just about every respect. A total run of 13 tanks
would be completed before the project was cancelled. In 1944, the M7 was
declared obsolete.
Guns: 37
mm Gun M5; 37 mm Gun M6; QF 6-pdr Mk. III; 75 mm Gun M3
Engines:
Twin Hercules, DRXBS (246 hp); Twin Cadillac, Series 42 (296 hp); Continental R-975-C1 (350 hp); Continental R-975E-C2 (400 hp); Ford GAF (500 hp)
Turrets
(Turret Armor (mm)): T7E2
(51/38/38); M7 (51/41/41)
Suspensions/Alternate
Hulls, Total Weight (metric tons): T7E2 VVSS (19.37); M7 VVSS
(24.03)
Hull Armor (mm): 38/32/25
Top Speed: 48 km/h
Crew: 5
(Driver; Gunner; Loader; Commander; Radio)
Parent: T7 Light
Children: T20, Nahuel
Sources:
Hunnicutt, R. P. Stuart. 1992.
Hunnicutt, R. P. Sherman. 2015.
I'd thought the M7 as a Tier IV lead in to the M4 would fix an issue in the current Medium tree of the M3 playing more like a TD and not matching the crew positions of the rest of the line. Move the M3 to be the Tier IV turretless TD in place of the T40. Maybe move the T40 to Tier V and start to branch out a complete turretless line. Would just need a Tier VI to fill the gap.
ReplyDeleteThe M8A1 could then lead off two turreted lines, or maybe just jigger the existing ones around.
The issue with that is that the M3 is distinctively a medium tank, despite its appearances. It also doesn't make much sense for the M7 to come before the M4, as it was meant to be an improvement over the M4 (despite the eventual outcome). I'd like to avoid that kind of chronological inconsistency whenever possible.
DeletePlus, here the M7 fits as part of a "failed prototype" branch that ends in the T95E6.