Inspired by a side discussion here:
Do military battle tanks have the ability to travel backwards as fast as they can travel forwards? I’m wondering whether, once you identify an asymmetry in the “footprint” on the ground from a passing tank, you can reliably determine what direction it was moving.
No where close to as fast as they can move forward.
So if they needed to cover, say, a mile of ground, they’d almost certainly be traveling forward?
yes unless they are in a fighting retreat, then they might want to go backwards (tanks generally are more heavily armored in front). Some tanks can reverse at a pretty decent clip (although still nowhere near fast as they can go forward). Russian tanks are notorious for their painfully slow reverse speeds, BTW.
The spirit of Stalin lives on.
The T-72 is the real offender here, only able to achieve ~4km/h in reverse. The T-64/T-80 can achieve the more reasonable ~20km/h. Still slower than the reverse speed of most modern Western MBTs; the M1A2 for example can do 42mph forwards and 25mph in reverse.
I’m told by a reliable and knowledgeable source that they can go much faster than that, at least forward.
If you remove the engine governor and want to destroy the drivetrain, sure, it can. Just not for very long.
The M1 Abrams’s powertrain consists of an AGT1500 multifuel gas turbine (originally made by Lycoming, now Honeywell) capable of 1,500 shaft horsepower (1,100 kW) at 30,000 rpm and 395 lb⋅ft (536 N⋅m) at 10,000 rpm and a six-speed (four forward, two reverse) Allison X-1100-3B Hydro-Kinetic automatic transmission. This gives it a governed top speed of 45 mph (72 km/h) on paved roads, and 30 mph (48 km/h) cross-country. With the engine governor removed, speeds of around 60 mph (97 km/h) are possible on an improved surface. However, damage to the drivetrain (especially to the tracks) and an increased risk of injuries to the crew can occur at speeds above 45 mph (72 km/h).
A lot of it is doctrinal from what I understand.
Western doctrine typically has tanks fighting from what’s called a “hull-down” position. Basically, the tank tries to just show its turret and gun above the crest of a rise/hill/ridge of some sort, to provide the smallest target and only expose the most robust armor. To do this successfully, you have to have a pretty good depression on your gun and some ability to go in reverse quick to get away/hide/reposition once they’ve seen you.
Here’s a diagram of “hull down”:
Hull down tank diagram - Hull down - Wikipedia
Soviet doctrine (I say Soviet, because all the Russian tanks are variants of old Soviet designs) emphasized attacking and as such, don’t emphasize reverse speed or gun depression. They also emphasize very small heights (for a tank), which also de-emphasizes gun depression.
So Western tanks tend to be able to go in reverse fairly quickly, while Russian ones can’t. And Russian ones tend not to have great gun depression either, so they’re not as good in hull-down positions.
Here’s an example of how the Ukrainians are taking advantage of this:
Mixing Leopard 2s And M-2s, The Ukrainian 47th Brigade Hits And Runs (forbes.com)
I believe it was Helmut Schmidt who was discussing WWII with some German soldiers and was heard to remark that Italian tanks had only reverse gears.
