The Northrop Grumman X-47 is a demonstration

unmanned combat aerial vehicle An unmanned combat aerial vehicle (UCAV), also known as a combat drone, colloquially shortened as drone or battlefield UAV, is an unmanned aerial vehicle (UAV) that is used for intelligence, surveillance, target acquisition, and reconnaissance ...

. The X-47 began as part of

DARPA The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Ad ...

's J-UCAS program, and is now part of the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

UCAS-D The United States Navy Unmanned Combat Air System Demonstrator (UCAS-D) program consists of * Northrop Grumman X-47A Pegasus * Northrop Grumman X-47B The Northrop Grumman X-47B is a demonstration unmanned combat aerial vehicle (UCAV) designed ...

program to create a carrier-based unmanned aircraft. Unlike the

Boeing X-45 The Boeing X-45 unmanned combat air vehicle is a concept demonstrator for a next generation of completely autonomous military aircraft, developed by Boeing's Phantom Works. Manufactured by Boeing Integrated Defense Systems, the X-45 was a part ...

, initial Pegasus development was company-funded. The original vehicle carries the designation X-47A Pegasus, while the follow-on naval version is designated

X-47B The Northrop Grumman X-47B is a demonstration unmanned combat aerial vehicle (UCAV) designed for aircraft carrier-based operations. Developed by the American defense technology company Northrop Grumman, the X-47 project began as part of DARPA' ...

Design and development

The US Navy did not commit to practical UCAV efforts until mid-2000, when the service awarded contracts of US$2 million each to

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and p ...

and

Northrop Grumman Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military techn ...

for a 15-month concept-exploration program. Design considerations for a naval UCAV included dealing with the corrosive salt-water environment, deck handling for launch and recovery, integration with command and control systems, and operation in a carrier's high electromagnetic interference environment. The Navy was also interested in using their UCAVs for reconnaissance missions, penetrating protected airspace to identify targets for the attack waves. The Navy went on to give Northrop Grumman a contract for a naval UCAV demonstrator with the designation of "X-47A Pegasus", in early 2001. The proof-of-concept X-47A vehicle was built under contract by

Burt Rutan Elbert Leander "Burt" Rutan (; born June 17, 1943) is a retired American aerospace engineer and entrepreneur noted for his originality in designing light, strong, unusual-looking, and energy-efficient air and space craft. He designed the recor ...

Scaled Composites Scaled Composites (often called simply Scaled) is an American aerospace company founded by Burt Rutan and currently owned by Northrop Grumman. It is located at the Mojave Air and Space Port in Mojave, California, United States. Founded to deve ...

at the

Mojave Spaceport The Mojave Air and Space Port at Rutan Field is in Mojave, California, United States, at an elevation of . It is the first facility to be licensed in the United States for horizontal launches of reusable spacecraft, being certified as a spa ...

. The Pegasus demonstrator looks like a simple black arrowhead with no vertical tailplane. It has a leading edge sweep of 55 degrees and a trailing edge sweep of 35 degrees. The demonstrator has retractable tricycle landing gear, with a one-wheel nose gear and dual-wheel main gear, and has six control surfaces, including two elevons and four "inlaids". The inlaids are small flap structures mounted on the top and bottom of the wing forward of the wingtips. The X-47A is powered by a single Pratt & Whitney Canada JT15D-5C small high-bypass turbofan engine with 3,190

lbf The pound of force or pound-force (symbol: lbf, sometimes lbf,) is a unit of force used in some systems of measurement, including English Engineering units and the foot–pound–second system. Pound-force should not be confused with pound-m ...

(14.2 kN) thrust. This engine is currently in use with operational aircraft such as the

Aermacchi S-211 The SIAI-Marchetti S.211 (later Aermacchi S-211) is a turbofan-powered military trainer aircraft designed and originally marketed by Italian aviation manufacturer SIAI-Marchetti. SIAI-Marchetti started to develop the S-211 in 1976 as a private v ...

trainer. The engine is mounted on the demonstrator's back, with the inlet on top behind the nose. The inlet duct has a serpentine diffuser to prevent radar reflections off the engine fan. However, to keep costs low, the engine exhaust is a simple cylindrical tailpipe, with no provisions for reducing radar or infrared signature. The X-47A's airframe is built of composite materials, with construction subcontracted out to Burt Rutan's Scaled Composites company, which had the expertise and tooling to do the job inexpensively. The airframe consists of four main assemblies, split down the middle with two assemblies on top and two on bottom. The X-47A was rolled out on 30 July 2001 and performed its first flight on 23 February 2003 at the

Naval Air Warfare Center Naval Air Warfare Centers are research organizations within Naval Air Systems Command. The centers are grouped within the following divisions: Aircraft division The Naval Air Warfare Center Aircraft Division (NAWCAD) conducts research, development, ...

China Lake Naval Air Weapons Station China Lake is a United States military facility in California. China Lake may also refer to: Places in the United States *China Lake, Kern County, California, an unincorporated community named for a nearby dry lake * Ch ...

, California. The flight test program did not involve weapons delivery, but Pegasus does have two weapons bays, one on each side of the engine, that may be each loaded with a single 500 pound (225 kg) dummy bomb to simulate operational flight loads. The Pegasus was also used to evaluate technologies for carrier deck landings, though the demonstrator did not have a

tailhook A tailhook, arresting hook, or arrester hook is a device attached to the empennage (rear) of some military fixed-wing aircraft. The hook is used to achieve rapid deceleration during routine landings aboard aircraft carrier flight decks at sea, ...

. Other issues related to carrier operations involve adding deck tie-downs without compromising stealth characteristics, and designing access panels so that they would not be blown around or damaged by strong winds blowing across the carrier deck. The J-UCAS program was terminated in February 2006 following the US military's

Quadrennial Defense Review The Quadrennial Defense Review (QDR) was a study by the United States Department of Defense that analyzes strategic objectives and potential military threats. The ''Quadrennial Defense Review Report'' was the main public document describing the Uni ...

. The

US Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Sig ...

and US Navy proceeded with their own UAV programs. The Navy selected Northrop Grumman's X-47B as its Unmanned Combat Air System Demonstrator (UCAS-D) program.

Variants

* X-47A *

* X-47C: Proposed larger version with a payload of and a wingspan of .

Specifications (X-47A)

References

External links

DARPA J-UCAS page

X-47 Pegasus UCAV-N Factsheet on air-attack.com
{{Scaled Composites Aircraft first flown in 2003 DARPA Edwards Air Force Base X-047A Scaled Composites Single-engined jet aircraft Unmanned stealth aircraft Tailless delta-wing aircraft 2000s United States experimental aircraft Unmanned military aircraft of the United States

Design and development

Variants

Specifications (X-47A)

See also

References

External links