By December 1981 , six AH - 64A prototypes had been built and the Army had awarded a production contract to the company .
In 1975 , the company won the contract for the AH - 64 Apache attack helicopter .
By December 1981 , six AH - 64 Apache     prototypes had been built and the Army had awarded a production contract to the company .
In 1975 , the company won the contract for the AH - 64 Apache attack helicopter .