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| X-47B UCAS-D | |
|---|---|
 |
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| The X-47B's first takeoff at Edwards AFB, California, in February 2011 | |
| Role | Unmanned combat air vehicle |
| Manufacturer | Northrop Grumman |
| First flight | 4 February 2011 |
| Primary user | United States Navy |
| Number built | 2 |
| Program cost | US$813 million[1] |
| Developed from | X-47A Pegasus |
| Developed into | X-47C UCLASS |
Contents
Design and development
Origins
The US Navy did not commit to practical UCAS efforts until 2000, when the service awarded contracts of US$2 million each to Boeing and Northrop Grumman for a 15-month concept-exploration program.[6] 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.[7]The J-UCAS program was terminated in February 2006 following the US military's Quadrennial Defense Review. The US Air Force and 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.[citation needed] A new weapon system will not be developed for the X-47B, but it will be able to carry existing weapons,[8] and has a full-sized weapons bay. To provide realistic testing, the demonstration vehicle is the same size and weight as the projected operational craft.[9][10][11]
The X-47B prototype rolled out from Air Force Plant 42 in Palmdale, California, on 16 December 2008. Its first flight was planned for November 2009, but the flight was delayed as the project fell behind schedule. On 29 December 2009, Northrop Grumman oversaw towed taxi tests of the aircraft at the Palmdale facility,[12] with the aircraft taxiing under its own power for the first time in January 2010.
Flight testing
The two X-47B demonstrators were planned to have a three-year test program with 50 tests at Edwards AFB and NAS Patuxent River, Maryland, culminating in sea trials in 2013.[16][17] However, the aircraft performed so consistently that the preliminary tests stopped after 16 flights.[18] 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 2,100 nautical miles (3,900 km), and an endurance of more than six hours.[19] In November 2011, the Navy announced that aerial refuelling equipment and software would be added to one of the prototype aircraft in 2014 for testing.[20] The demonstrator aircraft will never be armed.[18]
In 2012, Northrop Grumman tested a wearable remote control system, designed to allow ground crews to steer the X-47B while on the carrier deck.[21] In May 2012, AV-1 began high-intensity electromagnetic interference testing at Patuxent River, to test its compatibility with planned electronic warfare systems.[22] In June 2012, AV-2 arrived at Patuxent River to begin a series of tests, including arrested landings and catapult launches, to validate the ability of the aircraft to conduct precision approaches to an aircraft carrier.[23] The drone's first land-based catapult launch was conducted successfully on 29 November 2012.[24][25]
On 26 November 2012, the X-47B began its carrier-based evaluation aboard the USS Harry S. Truman (CVN-75) at Naval Station Norfolk, Virginia.[26] On 18 December 2012, the X-47B completed its first at-sea test phase. The system was remarked to have performed "outstandingly", having proved that it was compatible with the flight deck, hangar bays, and communication systems of an aircraft carrier. With deck testing completed, the X-47B demonstrator returned to NAS Patuxent River for further tests.[27] On 4 May 2013, the demonstrator successfully performed an arrested landing on a simulated carrier deck at Patuxent River.[28] The Navy launched the X-47B from the USS George H.W. Bush (CVN-77) on the morning of 14 May 2013 in the Atlantic Ocean, marking the first time that an unmanned drone was catapulted off an aircraft carrier.[29][30] On 17 May 2013, another first was achieved when the X-47B performed touch-and-go landings and take-offs on the flight deck of the USS George H.W. Bush while underway in the Atlantic Ocean.[31]
On 10 July 2013, the X-47B launched from Patuxent River and landed on the deck of the George H.W. Bush, conducting the first ever arrested landing of a UAV on an aircraft carrier at sea.[4] The drone subsequently completed a second successful arrested landing on the Bush, but a third attempt was diverted to the Wallops Flight Facility in Virginia after a technical problem was detected, aborting the planned carrier landing.[32] One of the drone's three navigational sub-systems failed, which was identified by the other two sub-systems. The anomaly was indicated to the mission operator, who followed test plan procedures to abort the landing. The Navy stated that the aircraft's detection of a problem demonstrated its reliability and ability to operate autonomously.[33] On 15 July 2013, with a different X-47B demonstrator, designated 501, another planned landing on the Bush was aborted due to technical issues.[34][35] Officials asserted that only one successful at-sea landing was required for the program, though testers were aiming for three, and only two out of four were achieved.[35] The Navy will continue flying the two X-47B demonstrators through 2014 due to criticism saying the service prematurely retired the testbeds.[36] They plan to deploy the aircraft to carriers three more times over two years. The first deployment is to occur in late 2013, and the second in 2014. The last is to be from late 2014 to early 2015 and demonstrate that unmanned aircraft can seamlessly work with the 70-plane carrier air wing.[37]
The Navy is using software from the X-47B to demonstrate unmanned refueling capabilities. On 28 August 2013, a contractor-flown Learjet 25 refueled from a Boeing 707 tanker. A pilot was on board the Learjet, but it flew autonomously as a surrogate aircraft uploaded with the X-47B's technology. Surrogates are often used as stand-ins for unmanned aircraft. The test was to demonstrate that unmanned and optionally-manned aircraft can have an automated aerial refueling capability, significantly increasing their range, persistence, and flexibility.[38] However, previously on 15 April 2013, it was announced by Capt. Jaime Engdahl, Navy UCAS program manager, that plans to demonstrate autonomous aerial refueling were cuts in the U.S. Navy’s fiscal 2014 budget.[39]
On 18 September 2013, the X-47B flew the 100th flight for the UCAS-D program. Objectives of the program were completed in July, which included a total of 16 precision approaches to the carrier flight deck, including five planned tests of X-47B wave-off functions, nine touch-and-go landings, two arrested landings, and three catapult launches.[40]
On 10 November 2013, flight testing for the X-47B continued on board the USS Theodore Roosevelt (CVN-71). During this phase, the X-47B's digitized carrier-controlled environment was tested which involved the interface between the unmanned aircraft and carrier personnel during launching, recovering, and flight operations. Such a digital environment offered increased flexibility and enhanced safety for carrier operations.[41]
Sea trials in summer 2014 are to make the X-47B able to clear the deck within 90 seconds or less, ideally 60 seconds, like a manned aircraft. The purpose is to allow its takeoff, landing, and ability to hold in a pattern able to be sandwiched between traditional, manned platforms without disruption to operations. Testing will be conducted on the USS Theodore Roosevelt with equipment to make it clear the deck quickly like an automated wing-folding capability instead manually commanded wing folding and an automatic tailhook retractor. The X-47B will also operate with a jet-blast deflector on deck for the first time, needed to conduct takeoffs without disrupting operating taking place behind it.[42]
On 10 April 2014, the X-47B performed its first night flight. Night flights are part developing operations for routine UAV activity, and the Navy will continue to develop procedures for it to act co-operatively with manned aircraft.[43]
Costs
The project was initially funded under a US$635.8-million contract awarded by the Navy in 2007. However, by January 2012, the X-47B's total program cost had grown to an estimated $813 million.[1] Government funding for the X-47B UCAS-D program was to run out at the end of September 2013, with the close of the fiscal year.[35]Awards
In March 2014, the X-47B won a 57th Annual Laureate Award for “extraordinary achievements” in aeronautics and propulsion hosted by Aviation Week. [44]On April 9, 2014, the National Aeronautic Association selected Northrop Grumman, the United States Navy, and the X-47B Team as the recipient of the 2013 Robert J. Collier Trophy.
Variants
Original proof-of-concept prototype with a 27.8-foot (8.5 m) wingspan, first flown in 2003.- X-47B
Proposed larger version with a payload of 10,000 lb (4,500 kg) and a wingspan of 172 ft (52.4 m).[45]
Specifications (X-47B)
- Crew: None aboard (semi-autonomous operation)
- Length: 38.2 ft (11.63 m)
- Wingspan: 62.1 ft extended/30.9 ft folded[46] (18.92 m/9.41 m)
- Height: 10.4 ft (3.10 m)
- Empty weight: 14,000 lb (6,350 kg)
- Max. takeoff weight: 44,567 lb (20,215 kg)
- Powerplant: 1 × Pratt & Whitney F100-220U turbofan
- Maximum speed: Subsonic
- Cruise speed: Mach 0.9+ (high subsonic)[47][48]
- Range: 2,100+ NM (3,889+ km)
- Service ceiling: 40,000 ft (12,190 m)
- 2 weapon bays, providing for up to 4,500 lb (2,000 kg) of ordnance[19]
- Provisions for EO/IR/SAR/ISAR/GMTI/MMTI/ESM[19]
See also
- Aircraft of comparable role, configuration and era
- AVIC Sharp Sword
- BAE Taranis
- Boeing Bird of Prey
- Boeing Phantom Ray
- Boeing X-45
- Dassault nEUROn
- EADS Barracuda
- General Atomics Avenger
- Lockheed Martin Polecat
- McDonnell Douglas X-36
- MiG Skat
- Northrop Grumman RQ-180
- Related lists
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