raketenjagdpanzer
08-04-2014, 10:31 AM
Note: I'm going to post up 1e mechanics for this later today...
In the early 1970s, the US Army was in need of a new main battle tank. In the 1960s, due to fortuitous events during the uprising in Czechoslovakia, The British had already determined that the 82mm/20lb gun its tanks used and the US 90mm were inadequate against the current and likely future generations of Soviet armor. The rumored T72 (really just an upgraded T62) and then hypothetical "T74" or "T80" tanks would totally outclass the M60A1 in terms of both firepower and protection. The 1973 Arab/Israeli conflict had shown that the Soviets had learned well from the TOW missiles captured from South Vietnamese forces: anti-tank guided missiles, in conjunction with powerful tank cannons, were the way forward.
NATO, particularly the United States and Germany, marked these developments with grave concern. The Soviets had the advantage (as it were) of a command economy and completely subservient client states and in almost all cases could force equipment standards on all of the Warsaw Pact; in NATO this was not the case. Battle rifles, SMGs, tank cannon and other war material varied across nation and army. A British soldier attached to a US unit would find himself using totally different equipment than he was used to. The US and West Germany wished to address this in the next generation of main battle tank, and coupled with the noted concerns above, began the MBT-70/KPz-70 project. Almost immediately the project hit a snag: the United States, with the exception of gun calibers, used imperial measurements. Germany had used the Metric system for decades. Just deciding on which measurements to use for machining almost scuppered the project from the outset.
Rather than being an evolutionary step up from the M60A1 (and its disastrous -A2 variant), and the successful but lightly armored Leopard-1, the MBT70 project was aimed at being a revolutionary vehicle. The main gun was to be a longer-barreled, heavier version of the M81-E1 that the M551 Sheridan was armed with. This gun, the (X)M150-E5, fired an assortment of 152mm rounds: antipersonnel, HE, HEAT, and APFSDS.
The MBT70, like the Sheridan, could also fire the Shillelagh anti-tank wire-guided missile. While lighter than the TOW or TOW-II, it still packed a considerable punch and teething problems with its combustible case and guidance computers had been overcome during the evolution of the M551 Sheridan.
The Germans, instead, opted for the Rheinmetall 120mm L/44, although they kept the option to purchase some "Raketenpanzers" open should the design meet their needs.
Due to continuing engineering problems between the US and German design teams, and mounting costs, the Germans eventually pulled out, developing the Leopard-II. Although the tank was essentially completed, and due to congressional pork barrel politics all "bugs" worked out through continued engineering stateside, the US Army elected to discontinue the project and instead turned its focus to the less complex but (as history would prove) vastly improved XM1, which would later become the M1 Abrams.
This left General Motors and Continental (the primary contractors for the MBT-70 project) with a dozen completed hulls, powerplants, turret assemblies and weapons, plus tooling. Normally these would be consigned to museums, cut apart for scrap, or sunk as reefs. However, the United States Marine Corps expressed an interest in the orphaned tank project. Receiving an initial go-ahead to continue the project at a low-rate of development and production from the Pentagon, the USMC continued to "tinker" with the tank until 1978, when it proclaimed the tank suitable to its needs and started a low-rate of initial procurement (LRIP), beginning with 60 tanks.
USMC variant requests included: an overpressure air-scrubbing NBC system, switching to the Honeywell AGT-1500 Gas Turbine used by the new XM-1 design, deleting the 20mm autocannon except for command variants, and other minor changes.
The M70A2 "Puller" (named after famed USMC Commandant Lewis Burwell "Chesty" Puller) was accepted in to USMC service in 1979. Models were produced from 1979-1988, totaling 407 tanks and spares. The vehicle served alongside the M60A1s and -A3s of the USMC, filling its need for a heavy main battle tank in Europe and elsewhere (most battalions were deployed to the Korean peninsula).
Starting in 1988, the USMC began to upgrade its M60A3s to -A4 standard, and expressed an interest in purchasing M1 Abrams tanks, with an eye to replacing the M70A2 by 1995. History, of course, had other plans...
...
What do you guys think?
I bolded the part about the Shillelagh's teething problems being overcome as I think that was a major problem (along with cost overruns and engine issues which the Marines fixed during LRIP) that held the MBT70 up.
Like I said I'll get some stats up later today.
In the early 1970s, the US Army was in need of a new main battle tank. In the 1960s, due to fortuitous events during the uprising in Czechoslovakia, The British had already determined that the 82mm/20lb gun its tanks used and the US 90mm were inadequate against the current and likely future generations of Soviet armor. The rumored T72 (really just an upgraded T62) and then hypothetical "T74" or "T80" tanks would totally outclass the M60A1 in terms of both firepower and protection. The 1973 Arab/Israeli conflict had shown that the Soviets had learned well from the TOW missiles captured from South Vietnamese forces: anti-tank guided missiles, in conjunction with powerful tank cannons, were the way forward.
NATO, particularly the United States and Germany, marked these developments with grave concern. The Soviets had the advantage (as it were) of a command economy and completely subservient client states and in almost all cases could force equipment standards on all of the Warsaw Pact; in NATO this was not the case. Battle rifles, SMGs, tank cannon and other war material varied across nation and army. A British soldier attached to a US unit would find himself using totally different equipment than he was used to. The US and West Germany wished to address this in the next generation of main battle tank, and coupled with the noted concerns above, began the MBT-70/KPz-70 project. Almost immediately the project hit a snag: the United States, with the exception of gun calibers, used imperial measurements. Germany had used the Metric system for decades. Just deciding on which measurements to use for machining almost scuppered the project from the outset.
Rather than being an evolutionary step up from the M60A1 (and its disastrous -A2 variant), and the successful but lightly armored Leopard-1, the MBT70 project was aimed at being a revolutionary vehicle. The main gun was to be a longer-barreled, heavier version of the M81-E1 that the M551 Sheridan was armed with. This gun, the (X)M150-E5, fired an assortment of 152mm rounds: antipersonnel, HE, HEAT, and APFSDS.
The MBT70, like the Sheridan, could also fire the Shillelagh anti-tank wire-guided missile. While lighter than the TOW or TOW-II, it still packed a considerable punch and teething problems with its combustible case and guidance computers had been overcome during the evolution of the M551 Sheridan.
The Germans, instead, opted for the Rheinmetall 120mm L/44, although they kept the option to purchase some "Raketenpanzers" open should the design meet their needs.
Due to continuing engineering problems between the US and German design teams, and mounting costs, the Germans eventually pulled out, developing the Leopard-II. Although the tank was essentially completed, and due to congressional pork barrel politics all "bugs" worked out through continued engineering stateside, the US Army elected to discontinue the project and instead turned its focus to the less complex but (as history would prove) vastly improved XM1, which would later become the M1 Abrams.
This left General Motors and Continental (the primary contractors for the MBT-70 project) with a dozen completed hulls, powerplants, turret assemblies and weapons, plus tooling. Normally these would be consigned to museums, cut apart for scrap, or sunk as reefs. However, the United States Marine Corps expressed an interest in the orphaned tank project. Receiving an initial go-ahead to continue the project at a low-rate of development and production from the Pentagon, the USMC continued to "tinker" with the tank until 1978, when it proclaimed the tank suitable to its needs and started a low-rate of initial procurement (LRIP), beginning with 60 tanks.
USMC variant requests included: an overpressure air-scrubbing NBC system, switching to the Honeywell AGT-1500 Gas Turbine used by the new XM-1 design, deleting the 20mm autocannon except for command variants, and other minor changes.
The M70A2 "Puller" (named after famed USMC Commandant Lewis Burwell "Chesty" Puller) was accepted in to USMC service in 1979. Models were produced from 1979-1988, totaling 407 tanks and spares. The vehicle served alongside the M60A1s and -A3s of the USMC, filling its need for a heavy main battle tank in Europe and elsewhere (most battalions were deployed to the Korean peninsula).
Starting in 1988, the USMC began to upgrade its M60A3s to -A4 standard, and expressed an interest in purchasing M1 Abrams tanks, with an eye to replacing the M70A2 by 1995. History, of course, had other plans...
...
What do you guys think?
I bolded the part about the Shillelagh's teething problems being overcome as I think that was a major problem (along with cost overruns and engine issues which the Marines fixed during LRIP) that held the MBT70 up.
Like I said I'll get some stats up later today.