X-47


X-47


Specifications{1,2,3}



General


Company: Northrop Grumman
Type: Carrier-based unmanned combat air vehicle (UCAV).
Goals: Naval unmanned combat air vehicle (UCAV-N) Advanced Technology Program (ATP).
Variants: X-47A / X-47B / X-47C
Primary Testing Facility Research: Mojave Spaceport
Flights: Not Available
Number of Prototypes Built: 4 (X-47A: 2, X-47B: 2)
Project Tenure: 2000-Present
Maiden Flight: 24 February 2003
Project Status: Ongoing

Dimensions


Wingspan: X-47A: 19 ft, 6 in (5.9 m); X-47B: 62 ft, 1 in (19.0 m)
Length: X-47A: 19 ft, 7 in (6.0 m); X-47B: 38 ft, 2 in (11.6 m)
Height: X-47A: 6 ft, 1 in (1.9 m); X-47B: 10 ft, 5 in (3.1 m)
Wing Area: X-47A: Not Available; X-47B: Not Available

Structure


Crew: None
Empty Weight: X-47A: 3,836 lbs (1,740 kg); X-47B: 14,000 lbs (6,350 kg)
Loaded Weight: X47A: Not Available; X47B: Not Available
Maximum Takeoff Weight: X-47A: 5,903 lb (2,495 kg); X-47B: 44,567 lb (20,215 kg)
Payload: X-47A: 1,000 lbs (454 kg); X-47B: 4,500 lbs (2,000 kg)


Powerplant


Powerplant: X-47A: 1x Pratt & Whitney Canada JT15D-5C turbofan; X-47B: 1x Pratt & Whitney F100-220U turbofan
Thrust: X-47A: 3,190 lbf (14.2 kN); X-47B: Unknown

Performance


Maximum Speed: X-47A: Not Available; X-47B: Not Available
Range: X-47A: 1,726 mi (2,778+ km); X-47B: 2,417+ mi (3,889+ km)
Rate of Climb: X47A: Not Available; X47B: Not Available
Service Ceiling: X-47A: 40,000+ ft (12,192+ m); X-47B: 40,000 ft (12,192 m)
Thrust to Weight Ratio: X47A: Not Available; X47B: Not Available
Wing Loading: X47A: Not Available; X47B: Not Available


X-47A: Information{1}


The Northrop Grumman X-47 is a demonstration Unmanned Combat Aerial Vehicle. The X-47 began as part of DARPA's J-UCAS program, and is now part of the United States Navy's UCAS-D program to create a carrier-based unmanned aircraft. Unlike the Boeing X-45, 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.


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 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 proof-of-concept X-47A vehicle was built under contract by Burt Rutan's Scaled Composites at the Mojave Spaceport. 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 (14.2 kN) thrust. This engine is currently in use with operational aircraft such as the Aermacchi S-211 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 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 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 an arrestor hook. 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 US Air Force 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: Original proof-of-concept prototype with a 19-foot (5.9-m) wingspan, first flown in 2003.

X-47B: Demonstrator aircraft, first flown in 2011.

X-47C: Proposed larger version with a payload of 10,000 lb (4,500 kg) and a wingspan of 172 ft (52.4 m).


X-47B: Information{2}


The Northrop Grumman X-47B is an American demonstration Unmanned Combat Aerial Vehicle (UCAV) which first flew in 2011. The X-47 project began as part of DARPA's J-UCAS program, and is now part of the United States Navy's UCAS-D (Unmanned Combat Air System Demonstration) program, which aims to create a carrier-based unmanned aircraft. Unlike the similar Boeing X-45, the development of the aircraft's predecessor, the X-47A Pegasus, was company-funded.


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 and Northrop Grumman for a 15-month concept-exploration program. Design considerations for a naval UCAV included dealing with the corrosive saltwater environment, deck handling for launch and recovery, integration with command and control systems, and operation in an aircraft carrier's high-electromagnetic-interference environment. The Navy was also interested in procuring UCAVs for reconnaissance missions, penetrating protected airspace to identify targets for following attack waves.

The J-UCAS program was terminated in February 2006 following the US military's Quadrennial Defense Review. The US Air Force 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. The X-47B carries no weapons, but has a full-sized weapons bay. In order to provide realistic testing, the demonstration vehicle is the same size and weight as the projected operational craft.

The X-47B prototype rolled out from Air Force Plant 42 in Palmdale, California, on December 16, 2008. Its first flight was planned for November 2009, but the flight was delayed as the project fell behind schedule. On December 29, 2009, Northrop Grumman oversaw towed taxi tests of the aircraft at the Palmdale facility, with the aircraft taxiing under its own power for the first time in January 2010.

The first flight of the X-47B demonstrator, designated Air Vehicle 1 (AV-1), took place at Edwards Air Force Base, California, on February 4, 2011. The aircraft first flew in cruise configuration with its landing gear retracted on September 30, 2011. A second X-47B demonstrator, designated AV-2, conducted its maiden flight at Edwards Air Force Base on November 22, 2011.

The two X-47B demonstrators are planned to have a three-year test program at Edwards AFB and NAS Patuxent River, Maryland, culminating in sea trials in 2013. The aircraft will be used to demonstrate carrier launches and recoveries, as well as autonomous inflight refueling with a probe and drogue. The X-47B has a maximum unrefueled range of over 2,000 miles (3,200 km), and an endurance of more than six hours. In November 2011, the Navy announced that aerial refuelling equipment and software would be added to one of the prototype aircraft in 2014.

The project was initially funded under a $635.8-million contract awarded by the Navy in 2007. However, by January 2012, the X-47B's program cost had grown to an estimated $813 million.


Variants


X-47A: Original proof-of-concept prototype with a 19-foot (5.9-m) wingspan, first flown in 2003.

X-47B: Demonstrator aircraft, first flown in 2011.

X-47C: Proposed larger version with a payload of 10,000 lbs (4,500 kg) and a wingspan of 172 ft (52.4 m).




References/Sources
  1. "Northrop Grumman X-47A Pegasus".Wikipedia. Accessed February 24, 2012.
  2. "Northrop Grumman X-47B".Wikipedia. Accessed February 24, 2012.
  3. "List of X-Planes".Wikipedia. Accessed February 24, 2012.
  4. Jenkins, Dennis, Tony Landis, and Jay Miller. American X-Vehicles: An Inventory -- X-1 to X-50 Centennial of Flight Edition. Monographs in Aerospace History. No. 31. June 2003.