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8th of October 1943

It was on this day in aviation history that the first prototype of the Northrop XP-56 Black Bullet was destroyed during a high-speed taxi run.

Northrop XP-56 Black Bullet, prototype #1, please note the extremely small vertical stabizer


The XP-56 was one of the experimental aircraft built during the Second World War. The initial idea for the XP-56 in 1939, then the Northrop N2B, was for an aircraft with no horizontal stabilizer and a small vertical tail. It was basically a flying wing with a small fuselage for the pilot and to house the engine. Its powerplant was to be a P&W X-1800 engine with two contra-rotating props in a pusher configuration. The US Army ordered Northrop to start the design work on the 22nd of June 1940, which led to the order of a prototype in de last week of September 1940. Shortly after the construction started P&W canceled the X-1800 engine project. Although considered as not a real suitable replacement the P&W R-2800 was to be the engine. As this engine was larger and heavier, it also required an alteration of the fuselage. The additional weight of the heavier engine and the modification increased the weight of the XP-56 by 2000lbs (910 kg) and reduced the aircraft's top speed by 12 knots (14 mph / 23 kph)

The XP-56 was constructed using a magnesium alloy in anticipation of a possible aluminum shortage due to the war effort. A special welding technique (Heliarc welding) was used in the construction of the aircraft.


Two prototypes were ultimately built:

  • Prototype 1 (41-786) After construction engine runs were started in March 1943, not very successful as the engine failed. A replacement engine was installed in August of that year. During taxi trials, yaw stability issues were discovered, after changing the brake system (which initially was the suspected cause) On the 30th of September 1943, it made the first flight of the XP-56 program. Stability problems were still encountered and ultimately traced to the vertical stabilizer, or its small size to be exact. It was enlarged to the same size as the ventral fin. During high-speed taxi tests (~113 knots / 130 mph / 210 kph) on this day, the 8th of October 1943, the left main gear tire failed. The aircraft became airborne for a short hop, crashed to the ground throwing the pilot free from the aircraft. The pilot, John Myers only had minor injuries and credited his Polohelmet for his survival

  • Prototype 2 (42-38363) It was completed in January 1944 and differed from the 1st prototype on some points. - Rudder control was redesigned - Vertical stabilizer enlarged - CofG was moved forward

The second prototype on one of its 10 flights

On its first flight, on the 23rd of March 1944, the pilot encountered some pitch control issues and yaw sensitivity. The flight only lasted 8 minutes. More flights were successfully made progressively increasing the flight time. Pitch control improved with the gear retracted. However, on the 10th flight, the pilot reported a severe nose-up tendency, lack of power, and excessive fuel consumption. Flight testing was stopped as it was considered too dangerous. After a year the project was stopped. It is currently in storage at the Smithsonian Institute in Washington, USA


Specifications of the XP-56 Black Bullet, not al accurate some are estimates as not all records for the program were kept;


General characteristics

  • Crew: one, pilot

  • Length: 27 ft 6 in (8.38 m)

  • Wingspan: 42 ft 6 in (12.96 m)

  • Height: 11 ft 0 in (3.35 m)

  • Wing area: 306 sq ft (28.44 m2)

  • Empty weight: 8,700 lb (3,955 kg)

  • Gross weight: 11,350 lb (5,159 kg)

  • Max takeoff weight: 12,145 lb (5,520 kg)

  • Powerplant: 1 × Pratt & Whitney R-2800-29 radial, 2,000 hp (1,492 kW)

Performance

  • Maximum speed: 465 mph (749 km/h, 404 kn) at 25,000 ft (7600 m)

  • Range: 660 mi (1,063 km, 570 nmi)

  • Service ceiling: 33,000 ft (10,061 m)

  • Rate of climb: 3,125 ft/min (15.88 m/s) at 15,000 ft (4600 m)

  • Wing loading: 37 lb/sq ft (181 kg/m2)

  • Power/mass: 0.18 hp/lb (0.96 kW/kg)

Armament

  • 2 × 20 mm (.79 in) cannons

  • 4 × .50 in (12.7 mm) machine guns

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