X-47 Pegasus

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NORTHROP GRUMMAN PEGASUS UCAV DEMONSTRATOR
Length	8.51 meters	27 feet 11 inches
Wingspan	8.48 meters	27 feet 10 inches
Height	1.74 meters	5 feet 8 inches
Empty weight	1,740 kilograms	3,835 pounds
Gross weight	2,495 kilograms	5,500 pounds
Maximum speed	subsonic
Endurance	> 1 hour
Unmanned aerial vehicle

The Northrop Grumman X-47A Pegasus is a demonstration Unmanned Combat Aerial Vehicle. The X-47 is part of DARPA's J-UCAS project.

Unlike the Boeing X-45, Pegasus development was company-funded. The initial vehicle carries the designation X-47A; a follow-on Naval version is designated X-47B.

The proof-of-concept X-47A vehicle was built under contract by Burt Rutan's Scaled Composites at the Mojave Spaceport. The roll out ceremony at Mojave was in July 2001 and the first flight was successfully completed in February 2003. The program was terminated on January 13, 2006 as part of the US Military's Quadrennial Defense Review.

Contents 1 History 2 Specifications (X-47A) 3 External links 4 Related content 5 See also

[edit] History

The US Navy did not commit to practical UCAV efforts until the summer of 2000, when the service awarded contracts of $2 million USD each to Boeing and Northrop Grumman 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 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.

Pegasus is powered by a single Pratt & Whitney Canada JT15D-5C small high-bypass turbofan engine with 14.2 kN (1,450 kgp / 3,190 lbf) thrust. This engine is currently in use with operational aircraft such as the Agusta S211A 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 UCAV'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 cheaply. The airframe basically consists of four main assemblies, split down the middle with two assemblies on top and two on bottom.

The Pegasus was rolled out on 30 July 2001 and performed its first flight on 23 February 2003 at the US Naval Air Warfare Center at China Lake, 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 225 kilogram (500 pound) 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 an arresting hook. Other issues related to carrier operations involve adding deck tie-downs without compromising stealth characteristics, and designing access panels so that they wouldn't be blown around or damaged by strong winds blowing across the carrier deck.

[edit] Specifications (X-47A)

General characteristics

• Crew: none
• Length: 19 ft 7 in (8.50 m)
• Wingspan: 19 ft 6 in (8.47 m)
• Height: 6 ft 1 in (1.86 m)
• Wing area: ft² (m²)
• Empty weight: 3,836 lb (1,740 kg)
• Loaded weight: 4,877 lb (2,212 kg)
• Max takeoff weight: 5,903 lb (2,678 kg)
• Powerplant: 1× Pratt & Whitney JT15D-5C (X-45A)
  Pratt & Whitney F100-220 (X-45B) turbofan, 3,190 lb_f (14.2 kN)

Performance

• Maximum speed: mph (km/h)
• Cruise speed: mph (km/h)
• Range: miles (km)
• Service ceiling: ft (m)
• Rate of climb: ft/min (m/s)
• Wing loading: lb/ft² (kg/m²)
• Thrust/weight: 0.65

Armament

None

[edit] External links

• X-47B UCAV
• Seattle Times
• Detailed X-47 description from AirForce-Technology.com

[edit] Related content

 

 

Designation sequence

X-44 - X-45 - X-46 - X-47 - X-48 - X-49 - X-50

 

 

[edit] See also

• List of experimental aircraft