The XP-31 or Curtiss Shrike of 1932-3 was an all-metal, low wing, strut-braced fighter design which drew heavily upon the characteristics of the manufacturer's A-8 Shrike (enclosed cockpit, trailing edge flaps and leading-edge slots), but failed to attain the A-8's production status. The sole prototype XP-31, at first designated XP-934, marked a step forward for Glenn L. Curtiss's fighter team but arrived on the scene just when the comparable Boeing P-26 'Peashooter' had already proven itself superior in most aspects of performance.
First flown in July 1932 with a 522kW Wright R-1820-4 Cyclone engine, the XP-31 was immediately found to be underpowered. Though the purpose seems unclear, the sole airframe was re-engined with a 447kW Curtiss V-1570 Conqueror powerplant which, in 1933 flight tests, offered no improvement of any kind. Slower than the P-26, short-legged with its scant 595km range, the XP-31 helped Curtiss to upgrade its design and structural thinking at a time when the monoplane was clearly the aircraft of the future. But it was also, in many respects, an anachronism. Its non-retractable landing gear and drag-inducing wing struts were the last to appear on a USAAC fighter. Furthermore the XP-31, although very small by comparison with other pursuit ships of its day, was unduly heavy. Swift in name only and apparently very demanding on maintenance resources, the XP-31 was rigorously tested and underwent various minor modifications in the
early 1930s, but it belonged to the past more than the future. It was not chosen for production and did not, directly, lead to any later designs. The existing XP-31 is understood to have been scrapped in 1935.
