The most famous P-51 Mustang fighter plane had its debut in 1942 with the Royal Air Force. It was supplied by the United States to the Allies to combat the Axis Forces. This first version was equipped with an Allison engine, but was no match for the enemy Bf-109 or FW-190 fighters. It was the base for the subsequent versions which were equipped with Rolls-Royce engines. This first P-51 served honorably in the U.S. Air Force in the Mediterranean and Far East operations.