As a result, the Army developed the M829A2 and M829A3 rounds, which featured increased-length penetrators and special tips to defeat the heavy ERA threat. The M829A3 round is the current wide-issue for M1A1 and M1A2 Abrams crews and likely can defeat the armor of most tanks in the world today, including early T-72B3s and T-90As which still use Kontakt-5 ERA.In the 1970s, the situation for NATO tank forces in Europe was grim. The program to develop the next generation battle tank for both Germany and the United States, the MBT-70, was about to crumble and fail, and the next generation of Soviet tanks was about to reach the front lines.(This first appeared late last year.)The tank forces of the U.S. and its allies were reliant on the aging M60 tank or roughly comparable analogues. Declassified CIA documents from the period shared a pessimistic estimate of the balance of forces: the Soviet tanks were more numerous and technically superior.Following the failure of the MBT-70, Congress forced the Army to begin a new tank program under strict cost and time limitations. A developmental concept paper (DCP) for this new tank was created in 1972 and approved in 1973. The DCP called for competitive evaluations, trialing of turbine versus diesel engines and concurrent operational and engineering trials.The armor and armament of the new tank, now dubbed the XM1, aimed to incorporate the latest developments in armor technology. The Army specified that the British-developed Chobham armor be incorporated into the design.