- Yes
- No
T70 Gun Motor Carriage - Soviet Trials
The “T-70 destroyer-tank” at the NIIBT proving grounds, spring of 1944.
Introduction and History:
The T70 Gun Motor Carriage was the prototype form of what would become the American M18 Hellcat tank destroyer. Developed in 1942-43 as a high speed tank destroyer, the T70 was designed with an emphasis on mobility and firepower, using the powerful 76mm M1 gun and a lightweight chassis to reach high speeds.
In 1943, a small number of T70 vehicles were sent to the Soviet Union under the Lend Lease program for testing and evaluation. Soviet engineers were intrigued by the torqmatic transmission and the high power to weight ratio, which gave the vehicle exceptional speed and agility. However, their assessments noted serious drawbacks: the armor was extremely thin, providing little protection, and internal space was cramped, especially around the gunner’s position. Additionally, visibility from within the fighting compartment was limited.
Shipping record of tank destroyers that arrived at Molotovsk and the equipment that accompanied them.
Unlike the GMC M10, which was formally accepted into Red Army service, the T70 never moved beyond the trial stage. After testing, the vehicles were not adopted or widely used, likely due to the Red Army’s preference for more robust and better armored self propelled guns like the SU-85 and SU-100. The T70s quietly disappeared into obscurity, remembered mostly as a footnote in the broader story of Allied cooperation and experimental vehicles evaluated by the USSR during World War II.
Overall, the T70 GMC’s armament was solid for a tank destroyer of its class, but the chassis left much to be desired and ultimately led to its rejection.
The Soviet evaluation concluded:
The American T70 SPG could not be recommended for import for the following reasons:
- Poor armor, which only protects against small arms fire and shell fragments.
- Excessive fuel consumption, several times higher than comparable SPGs under the same conditions.
- Reliance on high octane gasoline, increasing the risk of fire.
- Poor visibility from within the vehicle."
As noted earlier, the T70 prototypes were later refined and standardized into the M18 Hellcat. It seems the Americans were aware of these shortcomings as well. However, the upgrades were relatively minor and did little to address the vehicle’s fundamental flaws especially its poor off road performance. Similar issues appeared during trials of the T26E3 Pershing, which also used a torque converter and demonstrated the same high fuel consumption.
Specifications:
General Information
- Origin: United States of America
- Crew: 5 (Commander, Gunner, Loader, Driver, Assistant Driver)
- USSR Received for testing: 2
Dimensions
- Weight: 17.7 metric tons (39,000 lbs)
- Length: 5.3 m
- Width: 2.9 m
- Height: 2.5 m
Armament
- Primary: 76mm M1A1 Gun (45-60 rounds)
- Secondary: 1 × .50 cal (12.7 mm) M2HB machine gun (roof mount)
The penetration of the GMC T70’s gun had no issues.
- Photo #31: penetration of the left side with a 76 mm shell from the American M1A1 gun from a range of 2000 meters.
- Photo #32: Diagram of the penetration of the left side with a 76 mm shell from the American M1A1 gun from a range of 2000 meters.
Armor
- Thickness: 6.4-25.4mm (0.25-1 inch); mostly 12.7mm flat plate
- Armor type: Rolled homogeneous steel (RHA), welded construction
Engine and Performance
- Engine: Continental R-975-C4 9-cylinder radial
- Horsepower: 400 hp (298 kW)
- Top Speed: 89 km/h (55 mph) on road (high for the standards of that time)
- Range: 160-175 km (100-110 miles)
- Power-to-Weight Ratio: 22.6 hp/ton
More images
The mudguards on the tank destroyers were quickly lost.
This placement of ammunition was risky, but made reloading quicker.
Fuel consumption on dirt roads increased drastically.
When driving off-road, the light tank destroyer consumed more fuel than some heavy tanks.
Hill climbing trials.
Driving at a tilt.
The tank destroyer is fording a river.
Component layout of the GMC T70.
Diagram of the transmission on the American tank destroyer.
Armour diagram. As you can see, there isn’t much of it. The armour was sacrificed for high mobility.
Placement of crew members within the fighting compartment. Soviet testers had many issues with it.
Visibility from the T70.
Sources
M18 Hellcat - Wikipedia
https://www.reddit.com/r/TankPorn/comments/ris943/the_76mm_gun_motor_carriage_t70_m18_hellcat/
Redirecting...
Tank Archives: Hellcat: Highway Tank Destroyer
The M18 Hellcat Tank Destroyer - The Army Historical Foundation
M18 Gun Motor Carriage (Hellcat) Self-Propelled Tracked Tank Destroyer (TD)