Speed has always been at the center of aircraft design, particularly in the military realm. During World War 2, when turbojet technology finally arrived as a feasible propulsion scheme for aircraft, many designs emerged to take advantage of the new capabilities the engine offered. One of the key limitations were speed limits imposed by traditionally-designed airframes with straight surfaces - this required special attention in developing an aircraft to couple with a potent engine fit.
One of the concepts soon proven was the value of swept-back wings as this allowed reduced drag when cutting through the air at speed. The idea was long known in the field of aeronautics but propulsion schemes needed to catch up before the process could be proven effectively. There were challenges in overcoming the swept-back wing as instability occurred at low speed - low speeds critical to landing and taking off. Nevertheless, the swept-back wing became a stable of aircraft design since these days.
For Dr. Richard Vogt of German aircraft-maker Blohm and Voss, developer of many far-reaching aircraft seen during the war (at least on paper), the problem of high-speed flight was somewhat addressed through his P.202 proposal - the "swiveling wing" as it was. In the P.202, the wing mainplane was set to swivel on a center axis, directing the wings from a straight, conventional posture to one that was "swept". This reduced forward approaching drag and placed the portside mainplane section ahead of the cockpit and the starboard side section aft of center mass - in either case, sweep was accomplished. The wings were further mounted high on the fuselage so as to sit atop its swiveling gear buried within. The cockpit was set far forward over the nose and the tail unit was conventional with a single rudder and low-set horizontal planes. A wide-mouth intake was set under the chin of the aircraft to aspirate the proposed jet engine pairing. This pair exhausted through ports under the belly of the aircraft at the base of the tail. A traditional tricycle undercarriage was to be fitted for ground running but the height of the shoulder-mounted wings meant that the main legs were rather tall. The nose leg was to sit under the intake opening.
Power to the design was to come from 2 x Heinkel-Hirth HeS 011 series turbojet engines, each outputting up to 2,865lb of thrust.
Dimensions included a wingspan of 39.5 feet, a length of 32.8 feet and a height of 10.5 feet. Take-off weight was estimated at 11,905 lb.
Proposed armament was 2 x 30mm MK 108 automatic cannons installed in the nose.
In the P.202, the mainplanes would take-on their straight posture for the stability, drag and lift require during take-off and landing actions. When high-speed flight was called for, the sweep of the wing would be changed to accommodate this (up to 35-degrees sweep was achieved). It was thought that utilization of both forward-swept and rearward-swept surfaces would offset any general instability to be encountered during high-speed flight.
Nevertheless, the P.202 was never finished, constructed or flown before the end of the war in Europe arrived in May of 1945.
The concept of the "oblique wing" came into play once more when NASA developed its AD-1 (Ames-Dryden Model 1) through a design by Burt Rutan and manufacture by the Ames Industrial Company. A first-flight of this unique aircraft was recorded on December 21st, 1979 and it remained active into August of 1982. Only one example of this aircraft was completed that covered 79 test flights. Powered by a pair of Mircoturbo turbojets, the wings of the aircraft could pivot up to 60-degrees. A maximum speed of 200 miles per hour was recorded with a service ceiling of 12,000 feat reached.
Some performance figures on this page are estimated on the part of the author.
- X-Plane / Developmental
32.81 ft (10 m)
39.37 ft (12 m)
10.50 ft (3.2 m)
7,055 lb (3,200 kg)
11,905 lb (5,400 kg)
401 mph (645 kph; 348 kts)
38,993 feet (11,885 m; 7.38 miles)
2 x 30mm MK 108 cannons in the nose.
P.202 - Base Project Designation