Tank recovery at Cambrai (Film)

[CharlesBronson]

Tanks have 3 things that limit speed.
1, engine power
2, transmissions (includes clutches and steering gear)
3. Suspension.

Taking the last first few, if any, WW I tanks used springs on the road wheels. Ride is best described as rough even at 4-5mph.

WW I automotive (including heavy trucks) transmissions were rather crude. synchronized gears were extremely uncommon if available at all. Getting transmissions that could stand up to the weight of the large tanks and even a relatively low powered engine without breaking gear teeth was a challenge. And please remember that the engine used in the British MK IV tank was a 16 liter (976 cu in ?) six cylinder. It may have been only 105hp but 105hp at 1000rpm means 551 ft lbs of torque. putting that kind of twisting force on the input shaft and trying to move 27-29 tons even at a walking speed needs some heavy duty gears.

Decent aircraft engines were in short supply in 1917-18 (some license built Hispano V-8s weren't even lasting 20 hours) and the 150hp Hispano was only 11.7 liters. less torque than the Diamler.

BTW the British Whippet "light" tank

did use two bus engines. But Bus engines in WW I were closer to 45 hp than the 80-90hp of the late 30s.
Whippit could do a blistering 8.3mph but the tracks were still unsprung.

Your points are worthy but I feel like in they never used the best available technology for tanks in ww1, certaily not the british, some french tank like the Saint-Chamond were as heavy but faster (although not so good crossing trenches) and better armed with 75mm guns.

 

[GrauGeist]

Fully agree, SR.

Folks seem to forget that technology in the early 20th century was nothing like it was approaching mid-century. Engines were large, bulky, heavy and low-compression. The drive-drains were large, bulky, heavy and lacked the later alloy technology that would allow stronger drive components, preventing catastrophic failure under load.

The Renault FT was an impressive leap in AFV design and technology during the war, being a little over 7 tons (6,589kg) but managing a top speed of 5mph (7.7kph) with a 35 horsepower engine. It also had a

It was also one of the few WWI vintage tanks that actually saw active combat in WWII and served in various capacities as late as 1949.

 

[soulezoo]

Agreed on the Renault FT series. It was rather revolutionary and was a good first tank. If memory serves, the FT introduced both suspension for the wheels and a rotating turret.

It was the FT-17 that George Patton learned his stock in trade in WW I. Got him shot in the backside as I recall as well.

The one thing about the early tanks that was a common theme was that many more tanks were lost to mechanical breakdown than to enemy action.

 

[GrauGeist]

The FT had a well designed vertical-sprung suspension that was far more effective than contemporary designs. Most tanks had been using suspension designs more suited to heavy equipment, like road repair machines or farm tractors.

Patton's tanks used during the war were on loan from the French. The U.S. manufactured FT, the M1917, arrived in Europe too late to see any combat, however.