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Grumman X-29
A Grumman X-29 in flight
Type	Experimental Fighter
Manufacturer	Grumman
Maiden flight	1984
Primary user	DARPA
Number built	2

The Grumman X-29 was an experimental aircraft that explored a number of new technologies; the most immediately obvious being the forward-swept wings and canard control surface. The inherent aerodynamic instability of this arrangement required the use of computerized fly-by-wire control, and advanced composite materials were needed to make the wing sufficiently rigid without being unacceptably heavy. The X-29 first flew in 1984 and two X-29s were flight tested over the next decade.

Two X-29As were built by Grumman Aerospace Corporation, the first flight taking place in 1984. The aircraft were adapted from existing Northrop F-5A Freedom Fighter airframes^{[citation needed]} (after the proposal had been chosen over a competing one involving a General Dynamics F-16 Fighting Falcon). The modified design was known internally as the G-712. The test program of the two planes continued for over a decade, and on December 13, 1985 one of them became the first forward swept wing aircraft to fly in supersonic, level flight. The earlier Junkers Ju 287 had been the first jet aircraft with forward-swept wings.

A fiberglass scale model at the National Air and Space Museum

The X-29A demonstrated excellent control and maneuvering qualities at an angle of attack up to 45 degrees. There was also a decrease in turbulence. However, the wing configuration made the craft inherently unstable and it could fly only with the constant corrections (up to 40 per second) provided by the computerized flight control system. The system was made up of three redundant digital computers backed up by three redundant analog computers; either of the three could fly it on its own, but the redundancy allowed them to check for errors. Each of the three would "vote" on their measurements, so that if any one was malfunctioning it could be detected. It was estimated that a total failure of the system was as unlikely as a mechanical failure in an airplane with a conventional arrangement.

The first craft built is now on display in the National Museum of the United States Air Force at Wright-Patterson Air Force Base near Dayton, Ohio. The other craft is on display at the Dryden Flight Research Center on Edwards Air Force Base.

This aircraft article is missing some (or all) of its specifications. If you have a source, you can help Wikipedia by adding them.

• Crew: one pilot
• Payload: 4,000 lb (1,810 kg)
• Length: 48 ft 1 in (14.7 m)
• Wingspan: 27 ft 2 in (8.8 m)
• Height: 14 ft 3 in (4.3 m)
• Wing area: 188 ft² (57 m²)
• Empty weight: 13,800 lb (6,260 kg)
• Loaded weight: 17,800 lb (8,070 kg)
• Max takeoff weight: 17,800 lb (8,070 kg)
• Powerplant: 1× General Electric F404 turbofans, 16,000 lbf (71.2 kN)

• Maximum speed: Mach 1.6 (1,200 mph, 1,820 km/h)
• Service ceiling: 55,000 ft (16,800 m)

X-29 Cockpit

• American X-Vehicles, NASA

Portions of this article are based on public domain text from NASA.

• NASA's X-29 website
• NASA's X-29 factsheet
• Grumman X-29 at fighter-planes.com

Wikimedia Commons has media related to:

Grumman X-29

• Northrop F-5

• Ju 287
• Su-47

Designation sequence

X-26 - X-27 - X-28 - X-29 - X-30 - X-31 - X-32

List of experimental aircraft