By this time, there was essentially no chance for the P-60, since the P-47 and P-51 seemed to satisfy all the Army's needs for fighters. Nevertheless, the Army agreed to test the delayed XP-60E which had missed out on the May 1943 trials at Patterson Field. In January 1944, the XP-60E (Model 95D) was flown to Elgin Field for official tests. The engine was a Pratt & Whitney R2800-10 eighteen-cylinder radial offering 2000 hp. Empty weight was 8285 pounds, gross weight was 10,320 pounds, and maximum takeoff weight was 11,520 pounds. Dimensions were wingspan 41 feet 3 3/4 inches, length 33 feet 11 inches, height 12 feet 6 inches, and wing area 275 square feet. Maximum speed was 410 mph at 20,200, 391 mph at 24,200 feet, and 405 mph at 15,000 feet. An altitude of 15,000 feet could be attained in 4.8 minutes. Service ceiling was 38,000 feet. Normal range was 315 miles. Armament consisted of four 0.50-inch machine guns with 250 rpg mounted in the wings. USAAF test pilots found that the XP-60E did not compare very favorably in level flight performance with later fighters, but it did match them in climbing rate. The aircraft was sensitive to slight changes in flight condition and had to be constantly retrimmed. Stability in level flight was poor and the climing speed was difficult to maintain.
In May of 1944, Curtiss-Wright finally recognized that the P-60 was a lost cause, and indicated to the Army that they wanted to discontinue all further work on the project. However, the USAAF insisted that the company follow through on its agreement and complete at least one of the two YP-60A aircraft still under construction under the revised P-60A-1-CU contract. These aircraft had been redesignated YP-60E owing to the number of design modifications incorporated that were related to the XP-60E.
One of the YP-60As was to see the light of day as a YP-60E. This was the second YP-60A, serialled 43-32763. It flew for the first time on July 15, 1944, powered by a 2100 hp Pratt & Whitney R-2800-18 eighteen-cylinder radial engine driving a single four-bladed propeller. It differed from previous P-60s in having a bubble canopy over the cockpit and revised fuselage and vertical tail shapes, so that it ended up looking a lot like a P-47D-25 Thunderbolt. Empty weight of the YP-60E was 8225 pounds, gross weight was 10,270 pounds, and maximum takeoff weight was 11,520 pounds. Dimensions were wingspan 41 feet 3 3/4 inches, length 33 feet 11 inches, height 12 feet 6 inches, and wing area 275 square feet. Estimated maximum speed was 405 mph at 24,500. Initial climb rate was estimated at 4200 feet per minute. Service ceiling was 34,000 feet. Armament consisted of six 0.50-inch machine guns with 267 rpg mounted in the wings.