Lockheed Martin X-56

The Lockheed Martin X-56 is an American modular unmanned aerial vehicle that is being designed to explore High-Altitude Long Endurance (HALE) flight technologies for use in future military unmanned reconnaissance aircraft.

X-56
Rendering of the X-56A in flight
Role	Experimental aircraft
National origin	United States
Manufacturer	Lockheed Martin Skunk Works
First flight	26 July 2013
Primary users	NASA Air Force Research Laboratory
Number built	2

Design and development

Designed by Lockheed Martin's Advanced Development Programs, known informally as the Skunk Works,^[1] the aircraft was first revealed by Aviation Week,^[2] and is intended to research active flutter suppression and gust-load alleviation technologies. The X-56A is based on Lockheed's earlier UAV work, showing influence from the Polecat, Sentinel and DarkStar UAVs. The program calls for the construction of two 7.5 feet (2.3 m)-long fuselages and a wingspan of 27.5 ft,^[3] with four sets of wings being constructed for flight testing.^[4]

Operational history

The X-56A first flew on 26 July 2013,^[5] flying from Edwards Air Force Base; twenty flights were to be flown on behalf of the Air Force Research Laboratory before the aircraft would be handed over to NASA for further testing.^[6]

The first X-56A unmanned aircraft was severely damaged in a crash shortly after takeoff from the dry lakebed at Edwards AFB, California, on 19 November 2015, on its first flexible-wing flight to test active flutter suppression. The aircraft had previously made 16 flights with stiff wings to prove its operating envelope.^[7]

The second X-56A unmanned aircraft flew for the first time on 9 April 2015 while under operation by NASA.^[8] The aircraft flew eight flights with the stiff wings to clear its operating envelope.^[9] The vehicle then completed its first flight with the highly flexible wings on 31 August 2017.^[10]

One instability mode, body freedom flutter, was shown to be actively suppressed by the digital flight control at 110 kn (200 km/h), within its normal flight envelope. Slender, flexible and lighter low-drag wings would be enabled by flutter suppression.^[11]

X-56B was destroyed in a crash on 9 July 2021 after suffering an "anomaly in flight".^[12]

Specifications (X-56A)

Data from ^[5]

General characteristics

• Crew: 1 (flown by remote control from ground-based console)
• Length: 7.5 ft (2.3 m)
• Wingspan: 27.5 ft (8.4 m)
• Powerplant: 2 × Jetcat P400 turbojets, 88.7 lbf (0.395 kN) thrust each

Performance

• Maximum speed: 138.1 mph (222.3 km/h, 120.0 kn)

See also

Related lists

• List of experimental aircraft
• List of X-planes