Late 1942 saw the Merlin engine being tested in the Mustang airframes. The top speed
leapt to 710 km/h. (440 mph.) The P-51B was assembled in Los Angeles, the P-51C in Dallas.
Both used the Packard 1,133 kW. (1,520 hp.) V-1650-3 a US variant of the Merlin.
Specifications; Engine (one) 857 kW. (1,150 hp.) Allison V-1710-F3R, Packard
1,133 kW. (1,520 hp.) V-1650-3, V-1650-7, Wing Span; 11.29 m. (37' 1/2"),
Length; 9.81 m. (32' 2 1/2"), Maximum take-off weight; 5,206 kg. (11,600 lbs.),
Maximum level speed; 703 km/h. (437 mph.), Range; 1, 529 to 3,347 km. (950 to 2,080 miles)