Given the fact that it had ended the Pacific War of World War II through the bombing of the Japanese home islands, a strategic campaign that culminated in the destruction of Hiroshima and Nagasaki by single atomic bombs on 6 and 9 August 1945 respectively, the US Army Air Forces were well aware of the fact that the heavy bomber (especially when equipped with atomic weapons) was the new arbiter of total war. As it emerged from World War II, the USA had a monopoly on the design, construction and possession of atomic weapons, but appreciated that other countries including the USSR would soon try to match this capability. So major emphasis was placed on the protection of the continental USA from the approach of bombers which could be carrying nuclear weapons, and in the period immediately following the end of World War II, the USAAF therefore issued a requirement for a new turbojet-powered all-weather and night fighter with two-seat accommodation for the pilot and all important operator for the radar that would form the heart of the new warplane’s operational capabilities.
Curtiss-Wright was currently planning its CW-29 Blackhawk attack bomber design which was projected for prototype construction as the XA-43, but this was now cancelled so that its funding could be diverted to a type derived from the CW-29 with changes including automatically operated nose and tail barbettes, each fitted with two 0.5 in (12.7 mm) machine guns to complement the primary bomber-destroying armament of unguided air-to-air rockets carried internally in a pack which was lowered into the slipstream before the rockets were fired. This was soon altered to a more conventional arrangement of four 20-mm fixed forward-firing cannon. The USAAF ordered two prototypes of this CW-29A Blackhawk for evaluation with the official designation XP-87, and the first of these took shape in a handsome design based on an all-metal structure and a mid-wing configuration which was perfectly orthodox by the standards of the day with no move toward the advanced features such as swept wings that were beginning to feature on the drawing boards of the design teams of other US aircraft manufacturers.
Wholly orthodox
The Blackhawk was based on a semi-monocoque fuselage of essentially rectangular section with rounded-off corners: from front to rear, this fuselage carried the radar and fixed forward-firing armament, the pressurised cockpit under a clear-view ‘bubble’ canopy, fuel tankage, and tail unit. This last comprised single vertical and horizontal surfaces, the former including a tall fin carrying upper and lower rudder segments each fitted with an inset trim tab, and the latter including a tailplane located about two-fifths of the way up the fin and carrying balanced elevators each fitted with an inset two-section trim tab. The dihedralled wing extended from the sides of the central fuselage. Each half of the wing was tapered in thickness and chord to its only marginally rounded corners, and carried the standard combination of outboard ailerons and inboard flaps across most of the span of its trailing edges. The airframe was completed by the landing gear, which was of the tricycle type with two wheels on each unit, and while the nosewheel unit retracted forward into a well in the lower part of the forward fuselage, the main wheel units retracted forward into wells in the undersides of the engine nacelles.
The powerplant comprised four Westinghouse XJ34-WE-7 axial-flow turbojet engines each rated at 3,000 lb st (13.34 kN) dry, and these were installed in side-by-side pairs inside basically rectangular-section nacelles under each half of the wing.
The first XP-87 was trucked from the Curtiss-Wright facility at Columbus, Ohio, to Muroc Dry Lake, California, where it recorded its maiden flight on 5 March 1948. Soon after this the XP-87 was redesignated as the XF-87 as the US Air Force, which had succeeded the USAAF in June 1947, had replaced by P-for-Pursuit category with the F-for-Fighter category. The performance of the XF-87 was thought sufficiently promising for the USAF to place a June 1948 order for 57 XF-87A fighter and 30 RF-87A photographic reconnaissance aircraft. In October 1948, however, the Northrop XF-89 was showing still greater promise and the F-87 order was cancelled, as was the completion of the second prototype that was in the process of conversion to XF-87A standard with the revised powerplant of two General Electric J47-GE-15 axial-flow turbojet engines each rated at 5,200 lb st (23.13 kN) dry.
The XF-87 was the last warplane built by the Curtiss company in any of its forms and, with the exception of the X-19 experimental type of 1963, the final Curtiss aeroplane of any type.
Specification
Curtiss-Wright XF-87 Blackhawk
Type: all-weather and night fighter
Accommodation: pilot and radar operator side-by-side on ejection seats in the enclosed cockpit
Armament: (proposed) four 20-mm forward-firing cannon in a Martin conical nose barbette
Equipment: standard communication and navigation equipment, plus air interception radar, APS-3 gun-laying radar and a reflector gun sight
Powerplant: four Westinghouse XJ34-WE-7 or -9 axial-flow turbojet engines each rated at 3,000 lb st (13.34 kN) dry
Fuel: internal 1,392 US gal (1,159.1 Imp gal; 5269.3 litres) plus provision for 1,208 US gal (1,005.9 Imp gal; 4572.75 litres) of auxiliary fuel; external fuel none; no provision for inflight refuelling
Wingspan: 60 ft 0 in (18.29 m); area 600.00 sq ft (55.74 m²)
Fuselage: length 62 ft 10 in (19.15 m); height 20 ft 0 in (6.10 m)
Weights: empty 29,935 lb (12671 kg); normal take-off 39,875 lb (18087 kg); maximum take-off 49,900 lb (22635 kg)
Performance: maximum level speed 507.5 kt (584 mph; 940 km/h) at sea level declining to 462 kt (532 mph; 856 km/h) at 29,300 ft (8930 m); cruising speed 391 kt (450 mph; 724 km/h) at optimum altitude; initial climb rate 5,500 ft (1676 m) per minute; climb to 35,000 ft (10670 m) in 13 minutes 48 seconds; service ceiling 45,500 ft (13870 m); maximum range 1,890 nm (2,175 miles; 3500 km); typical range 868.5 nm (1,000 miles; 1609 km)