M1A2(1993). An alternate version of this tank

[ReconGuy02]

So, basically, the title. As tank-experts know, IOTL M1A2 version was seriously cutted down. Basically, this was M1A1HA with CITV. But what if Cold War never ended? I heard they're planned increase armor to values upto IOTL modern versions of M1A2, and mount new FCS, mount new 140mm gun with length L/55, etc, etc...
End of a
Cold War end badly hit US tank engineering. Budget was cutted down, and many projects died.
I have a tip how it should've looked

 

[ReconGuy02]

Plz, don't blame me for English. I'm 15 years old and living in Ukraine

 

[Riain]

What would it weigh, and how would that impact on mobility?

 

[RamscoopRaider]

Your picture is that of the M1 Component Advanced Technology TestBed (CATTB), I believe that was not really planned to be deployed. It was I think a testbed for the Block III tank, which was supposed to be the M1A3, but ended up its own thing. That was still cancelled by the end of the Cold War. The Block III was to possibly have a 140mm gun L61, but the Army had not decided whether to field it with a lightweight 120mm to start with before it was cancelled, the weight was I think 62 tons (goal was 57 tons, but 62 was expected)

 

[SsgtC]

What would it weigh, and how would that impact on mobility?

Unless they were also planning a new engine? This is a wild assed guess, but maybe if they replaced the Original 1,500hp turbine with a 2,000hp diesel they might be able to keep the power to weight ratio close

 

[RamscoopRaider]

Unless they were also planning a new engine? This is a wild assed guess, but maybe if they replaced the Original 1,500hp turbine with a 2,000hp diesel they might be able to keep the power to weight ratio close

The CATTB had a 1450HP diesel, of course the CATTB did not weigh significantly more than the base Abrams, and had a better suspension, so mobility was the same

 

[BlondieBC]

Your picture is that of the M1 Component Advanced Technology TestBed (CATTB), I believe that was not really planned to be deployed. It was I think a testbed for the Block III tank, which was supposed to be the M1A3, but ended up its own thing. That was still cancelled by the end of the Cold War. The Block III was to possibly have a 140mm gun L61, but the Army had not decided whether to field it with a lightweight 120mm to start with before it was cancelled, the weight was I think 62 tons (goal was 57 tons, but 62 was expected)

Any idea how they planned to shed five tons of weight?

 

[RamscoopRaider]

Any idea how they planned to shed five tons of weight?

Block III at least had an autoloader, and planned to drop crew to 3 so smaller vehicle. New smaller, lighter powerpack, and new suspension saved the rest, estimate was 57-62 tons, with 62 tons being considered most likely. Of course by using a lightweight 120mm instead of a 140mm they would probably save more weight, given that the 140mm was meant to deal with a Soviet Tank expected to appear in the late 90's that never did, it was unneccesary

 

[Crowbar Six]

Rheinmetal had a 140mm on the drawing board which also got cancelled at the end of the Cold War. Later on they decided that evolving penetrator designs for existing 120mm cannon would be capable of dealing with any future reasonably sized MBT even with advanced composite armour schemes.

 

[BlondieBC]

Block III at least had an autoloader, and planned to drop crew to 3 so smaller vehicle. New smaller, lighter powerpack, and new suspension saved the rest, estimate was 57-62 tons, with 62 tons being considered most likely. Of course by using a lightweight 120mm instead of a 140mm they would probably save more weight, given that the 140mm was meant to deal with a Soviet Tank expected to appear in the late 90's that never did, it was unneccesary

Thanks.

How much did eliminating one crew man save?

 

[RamscoopRaider]

Thanks.

How much did eliminating one crew man save?

That I don't know, only specifics I've seen were a half ton on the suspension and 50% on the powerpack. Some of the more ambitious plans included a low profile unmanned turret for even more weight reduction, but unsure on amount

 

[ReconGuy02]

There was a XM964 SABOT for 140mm.
Rumors saying that this SABOT was able to pen as twice as M829A1.

 

[ReconGuy02]

Bump

 

[RamscoopRaider]

There was a XM964 SABOT for 140mm.
Rumors saying that this SABOT was able to pen as twice as M829A1.

Yes but it is also much bigger, reducing how much ammo can be carried and being much more awkward to load/handle. Given that once the USSR imploded there was no threat of a Soviet supertank coming along in the 90's, so the US could make do with the intermediary M829A2 in 1994 and wait until 2003 for M829A3 with similar performance in a smaller package

The M1A1 only carries 40 120mm rounds, and the M1A2 42. Switching to 140mm would massively reduce the amount of ammo that could be carried, just like switching form 105mm did (55 rounds). If that is the only way then yes, the US would do that, but given that the fall of the USSR happened, they could wait and avoid that trade-off through better technology

 

[ReconGuy02]

Yes but it is also much bigger, reducing how much ammo can be carried and being much more awkward to load/handle. Given that once the USSR imploded there was no threat of a Soviet supertank coming along in the 90's, so the US could make do with the intermediary M829A2 in 1994 and wait until 2003 for M829A3 with similar performance in a smaller package

The M1A1 only carries 40 120mm rounds, and the M1A2 42. Switching to 140mm would massively reduce the amount of ammo that could be carried, just like switching form 105mm did (55 rounds). If that is the only way then yes, the US would do that, but given that the fall of the USSR happened, they could wait and avoid that trade-off through better technology

It was created to penetrate FST-2.
M829A1/2 could've easily pen FST-1 (T-80U)

 

[RamscoopRaider]

It was created to penetrate FST-2.
M829A1/2 could've easily pen FST-1 (T-80U)

And?

With the end of the Cold War the US does not need massive amounts of extra penetration out of its tank guns right away. That can wait and be done at a reasoned pace with improved 120mm rounds that are not going to require substantially reducing the number of rounds carried by its tanks

 

[Dathi THorfinnsson]

Unless they were also planning a new engine? This is a wild assed guess, but maybe if they replaced the Original 1,500hp turbine with a 2,000hp diesel they might be able to keep the power to weight ratio close

The CATTB had a 1450HP diesel, of course the CATTB did not weigh significantly more than the base Abrams, and had a better suspension, so mobility was the same

New smaller, lighter powerpack

That I don't know, only specifics I've seen were a half ton on the suspension and 50% on the powerpack

How the heck is a diesel supposed to weigh less than turbine??.
Surely the whole point of the (fuel guzzling) turbine was to save space and weight.

 

[RamscoopRaider]

How the heck is a diesel supposed to weigh less than turbine??.
Surely the whole point of the (fuel guzzling) turbine was to save space and weight.

By being ~20 years newer, the AGT 1500 turbine goes back to 1965 in conception and was field tested in 1971, the planned diesel is much newer

Plus it is talking about the powerpack as a whole, not just the engine, but the transmission and other supporting systems, where I imagine much of the weight savings is

 

[History Learner]

And?

With the end of the Cold War the US does not need massive amounts of extra penetration out of its tank guns right away. That can wait and be done at a reasoned pace with improved 120mm rounds that are not going to require substantially reducing the number of rounds carried by its tanks

OP specifies the Cold War continues on.

 

[Blue cat]

OP specifies the Cold War continues on.

I'd be curious to see the details of the projectile length for the 140mm vs the enhanced 120mm designs that were historically fielded after the Cold War.

My limited understanding of thing s is that the ability of the 120 mm rounds to have long projectiles that extended well into the cartridge case of the fixed 120 mm round has played a role in keeping the 120mm gun viable.

I seem to recall the 140mm would have used separately loaded ammunition which may have put some limits on the length of the projectile ?