The second XP-40Q s/n 42-45722, later NX300B - (USAAF)

The XP-40Q was the project designation for the P-40Q, a new fighter that be relatively modern compared to the existing P-40 variants. The new fighter was to be very different looking aircraft to the rest of the family and probably not that good looking. The main differences being the bubble canopy (on the second and third aircraft) and reduced chin cowl. There was three of these aircraft produced using two P-40K's (s/n's 42-9987 and 42-45722) and a P-40N (s/n 43-24571). The first ZP-40Q was a P-40K-10, s/n 42-9987 that was fitted with a new cooling system, with a four blade propeller and longer nose. The radiators were moved under the fuselage with the intakes between the undercarriage legs. The second ZP-40Q was a P-40K, s/n 42-45722 that had a reduced chin cowl installed, four blade propeller, clipped wing tips (at a later date), with an Allison V-1710-121 fitted with a 2-stage supercharger and water injection that was capable of 1425hp and powering the aircraft up to 422 mph. The third XP-40Q was a P-40N, s/n 43-24571 and basically had the same modification as the second.

The second XP-40Q was the only one to survive the scrap heap and was sold to Joe Zeigler for a few hundred dollars. It was given the civil registration NX300B and was planed to compete in air races with the number 82. It was an unauthorized starter in the Thompson Trophy race  of 1947, where it was running in forth place when the engine caught fire and the pilot bailed out, consequently the aircraft crashed and exploded.