The XP-60B project got a new lease of life after the R-2800-10 engine was installed on it with a conventional four-blade propeller and a nearly entirely similar XP-60C design without any significant changes. The aircraft was renamed the XP-60E,but in the first flight it went only on May 26, 1943, when the engine problems were fixed.
So, by the summer of 1943, USAAC had a choice of three similar models and, in order to finally decide on the main one, back in April at Patterson Field airfield began comparative tests of all the samples presented. Then it turned out that the HR-60S can not get the nominal power of the engine and the fighter did not show the required TTH, which were even slightly lower than the latest modifications of the R-47D and P-51B. After such an unexpected turn of events, the order was reduced from 500 to 2 prototype aircraft, thus “killing” the program of construction of R-60A-1-CU fighters.
In January 1944, the prototype was transferred to Eglin Field Airfield, where the official test program was launched by army pilots. The problems, which have not been solved on the HS60A’S aircraft, have been fully identified here. The fighter was too unstable in flight, and trying to deviate from the course or lay an unnecessarily steep turn. For this reason, at maximum speed, it became too heavy, which did not like the pilots. Eventually, Curtiss had to admit that the program had failed.
In turn, the army aviation insisted that the two prototypes were still finished with the construction in accordance with the previously signed contract. These prototype aircraft were needed by USAAC rather for experimental purposes, as their mass production was not planned. However, only one YP-60A fighter was completed, and the second was brought to the level of the last modification and was designated YP-60E (serial number 43-32763). It installed the engine 18-cylinder engine R-2800-18 with a four-blade propeller, as well as redesigned the cockpit lantern and vertical plumage, likening them to similar elements of the fighter P-47D-25. Curtiss pilots performed only two flights on the YR-60E, the first of which took place on July 15, 1944, and then the aircraft was transferred to Wright Field Air Force Base for testing. The further fate of the last fighter of the R-60 series was quite prosaic. Not having any need for this aircraft the USAF in 1945 got rid of it as a surplus of products. The aircraft was purchased by James Dessano and prepared for the 1947 National Air Races. All military equipment and weapons were removed from the YP-60E fighter, the civilian registration code NX21979 and the number “90” were repainted and assigned. However, failures haunted him here – in the qualifying flight the plane crashed and suffered such severe damage that it did not make sense to restore it.
Of course, the fighter R-60 had a good chance of success, but design flaws and, most importantly, the failure of engines did not allow to fully unleash the potential of the fighter. Perhaps, if the war began for America a couple of months later, Curtiss would have been able to build 100-200 aircraft superior to the main R-39 and P-40 fighter jets at the time. However, the U.S. Army Aviation made completely different calculations, twice cancelling earlier orders and not allowing to build at least an installation batch of aircraft. This is the end of the history of the HR-60 aircraft.
|Engine type||1 DD Pratt Whitney R-2800-10|
|Power||1 x 2100hp|
|Weapons:||4 x 12.7 mm machine guns mounted in the wing.|