The Curtiss-Wright XP-55 Ascender prototype was born out of a United States Army Air Corps request for a higher-performance, more heavily armed fighter with improved pilot visibility over existing aircraft. The brief specifically allowed, and suited, unconventional designs. And if the XP-55 Ascender was one thing, it was unconventional.
The Curtiss Wright XP-55 Ascender featured highly-swept wings, a canard configuration and a pusher propeller. Because of the lack of a conventional tail the rudders were located on the wingtips. The elevator function was handled by the carnards. One of the XP-55 Ascender’s most unusual features was the propeller jettison lever inside the cockpit. This allowed the pilot to release the propeller from the aircraft before bailing out, ensuring he wasn’t chopped to pieces during his escape.
After some experimentation with wind tunnel models and full-scale flying models, Curtiss-Wright received an order from the USAAC for three XP-55 Ascender prototypes in July of 1942. Originally the XP-55 Ascender had been designed to utilize Pratt & Whitney’s in-development X-1800 engine – which was expected to produce 2,200 horsepower. But problems, delays and the eventual cancellation of this engine meant they were forced to redesign the aircraft to accept a far less powerful V-1710-95 engine which offered 1,275 horsepower.
The first XP-55 Ascender (serial number 42-78845) was completed on July 13th 1943. It made its first flight days later on the 19th. The pilot, J. Harvey Gray, reported that the takeoff run was excessively long. To resolve this problem Curtiss-Wright’s engineers increased the size of the forward canards. At the same time the aileron up trim was interconnected with the flaps so that it operated when the flaps were lowered- resulting in additional lift at low speed.
On November 15th 1943 the XP-55 Ascender program suffered its first major incident. Curtiss test pilot Harvey Gray was evaluating the first prototype’s high-altitude stall performance when the aircraft suddenly flipped over on its back and went into an uncontrolled upside-down descent. Gray was unable to regain control of the aircraft and it plummeted 16,000 ft (4,900 m) before Gray was able to bailout to safety. The aircraft smashed to the ground, still inverted, and was almost completely flattened by the impact.
The second XP-55 Ascender (serial number 42-78846) recieved a few updates over the original. The nose elevators were slightly larger and the there was a change from balance tabs to spring tabs on the ailerons. It took to the skies for the first time on January 9th 1944. To make sure the same fate didn’t befall this aircraft, all test flights were restricted so that the stall zone was avoided.
The third and final prototype Curtiss-Wright XP-55 Ascender (Serial No. 42-78847) was flown on April 25th 1944. It featured several upgrades over the previous two aircraft. The stall issue was greatly improved by the addition of four-foot wingtip extensions and by increasing the available movement of the nose elevator. This aircraft was also fitted with four 0.50 calibre machine guns.
Because of the significant improvement in performance the third prototype offered, the second prototype was upgraded to the same standard. This aircraft then underwent official USAAF flight trials.
The results weren’t good. The Curtiss-Wright XP-55 Ascender never achieved the sort of performance that was originally promised. Hardly surprising considering it was massively underpowered. Also, by 1944 the new era of jet fighters were beginning to emerge, and these almost overnight rendered propeller-powered prototype fighter aircraft obsolete. After testing, the US military showed no further interest in the design and all further development of the aircraft was halted.
Tragically that wasn’t the end of the Curtiss-Wright XP-55 Ascender story. Although the program was cancelled there were still two airworthy aircraft. On 27th May 1945 XP-55 42-788847, the third aircraft, made an appearance at the War Bond Air Show in Dayton, Ohio. During its display flight it crashed, killing the pilot and two more people on the ground.
The second aircraft still survives and is currently on display at the Air Zoo in Kalamazoo, Michigan. It is on long-term loan from the Smithsonian’s National Air and Space Museum in Washington D.C..