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Sikorsky UH-60 Black HawkFrom Wikipedia, the free encyclopediaThis article is about the US Army military versions and operators of the S-70 family. For USAF variants, seeSikorsky HH-60 Pave Hawk. For an overview of the S-70 family and for its civilian models and operators, seeSikorsky S-70.UH-60 Black Hawk

A UH-60L Black Hawk flies a low-level mission over Iraq in January 2004.

RoleUtility helicopter

ManufacturerSikorsky Aircraft Corporation

First flight17 October 1974

Introduction1979

StatusIn service

PrimaryusersUnited States ArmyRepublic of Korea ArmyColombian Armed ForcesTurkish Armed Forces

Produced1974present

Number builtabout 4,000[1]

Unit costUH-60: US$21.3million (avg. U.S. procurement, 2012)[2]

Developed fromSikorsky S-70

VariantsSikorsky SH-60 SeahawkSikorsky HH-60 Pave HawkSikorsky HH-60 Jayhawk

TheSikorsky UH-60 Black Hawkis a four-bladed, twin-engine, medium-liftutility helicoptermanufactured bySikorsky Aircraft. Sikorsky submitted the S-70 design for theUnited States Army's Utility Tactical Transport Aircraft System (UTTAS) competition in 1972. The Army designated the prototype as theYUH-60Aand selected the Black Hawk as the winner of the program in 1976, after a fly-off competition with theBoeing Vertol YUH-61.The UH-60A entered service with the U.S. Army in 1979, to replace theBell UH-1 Iroquoisas the Army's tactical transport helicopter. This was followed by the fielding of electronic warfare and special operations variants of the Black Hawk. Improved UH-60L and UH-60M utility variants have also been developed. Modified versions have also been developed for theU.S. Navy,Air Force, andCoast Guard. In addition to U.S. Army use, the UH-60 family has been exported to several nations. Black Hawks have served in combat during conflicts inGrenada,Panama,Iraq,Somalia, theBalkans,Afghanistan, and other areas in theMiddle East.Contents[hide] 1Development 1.1Initial requirement 1.2Upgrades and variations 2Design 3Operational history 3.1United States 3.2Colombia 3.3Israel 3.4Mexico 3.5People's Republic of China 3.6Taiwan (Republic of China) 3.7Sweden 3.8Turkey 3.9Other and potential users 4Variants 4.1Utility variants 4.2Special purpose 4.3Export versions 4.4S-70A 5Military operators 6Specifications (UH-60L) 7See also 8References 8.1Notes 8.2Citations 8.3Bibliography 9External linksDevelopment[edit]Initial requirement[edit]In the late 1960s, the United States Army began forming requirements for a helicopter to replace theUH-1 Iroquois, and designated the program as the Utility Tactical Transport Aircraft System (UTTAS). The Army also initiated the development of a new, common turbine engine for its helicopters that would become theGeneral Electric T700. Based on experience in Vietnam, the Army required significant performance, survivability and reliability improvements from both UTTAS and the new powerplant.[3]The Army released its UTTAS request for proposals (RFP) in January 1972.[4]The RFP also included air transport requirements. Transport aboard theC-130limited the UTTAS cabin height and length.[5]The UTTAS requirements for improvedreliability,survivabilityand lowerlife-cycle costsresulted in features such as dual-engines with improvedhot and highaltitude performance, and amodular design(reduced maintenance footprint); run-drygearboxes;ballistically tolerant, redundant subsystems (hydraulic, electrical andflight controls);crashworthycrew (armored) and troop seats;dual-stage oleomainlanding gear; ballistically tolerant, crashworthy main structure; quieter, more robustmainandtailrotor systems; and aballistically tolerant, crashworthyfuel system.[6]Four prototypes were constructed, with the first YUH-60A flying on 17 October 1974. Prior to delivery of the prototypes to the US Army, a preliminary evaluation was conducted in November 1975 to ensure the aircraft could be operated safely during all testing.[7]Three of the prototypes were delivered to the Army in March 1976, for evaluation against the rivalBoeing-Vertoldesign, theYUH-61A, and one was kept by Sikorsky for internal research. The Army selected the UH-60 for production in December 1976. Deliveries of the UH-60A to the Army began in October 1978 and the helicopter entered service in June 1979.[8]

UH-60A Black Hawks overPort Salinasduring theinvasion of Grenada, 1983. The conflict saw the first use of the UH-60.Upgrades and variations[edit]After entering service, the helicopter was modified for new missions and roles, including mine laying and medical evacuation. An EH-60 variant was developed to conduct electronic warfare and special operations aviation developed the MH-60 variant to support its missions.[9]Due to weight increases from the addition of mission equipment and other changes, the Army ordered the improved UH-60L in 1987. The new model incorporated all of the modifications made to the UH-60A fleet as standard design features. The UH-60L also featured more power and lifting capability with upgraded T700-GE-701C engines and a stronger gearbox, both developed for theSH-60B Seahawk.[10]Its external lift capacity increased by 1,000lb (450kg) to 9,000lb (4,100kg). The UH-60L also incorporated the automatic flight control system (AFCS) from the SH-60 for better flight control due to handling issues with the more powerful engines.[11]Production of the L-model began in 1989.[10]

UH-60s equipped with machine guns nearAn Najaf, Iraq in May 2005.Development of the next improved variant, the UH-60M, was approved in 2001, to extend the service life of the UH-60 design into the 2020s. The UH-60M incorporates upgraded T700-GE-701D engines and improved rotor blades. It also features state of the art electronic instrumentation, flight controls and aircraft navigation control. After the U.S. DoD approved low-rate initial production of the new variant,[12]manufacturing began in 2006,[13]with the first of 22 new UH-60Ms delivered in July 2006.[14]After an initial operational evaluation, the Army approved full-rate production and a five-year contract for 1,227 helicopters in December 2007.[15]By March 2009, 100 UH-60M helicopters had been delivered to the Army.[16]In the 1 May 2011 operation that killedOsama bin Laden, it emerged that the160th Special Operations Aviation Regiment, which operated the helicopters during the raid, used a highly modified version of the UH-60. Features apparently include a modified tail section with extra blades on the tail rotor and other additions which significantly lowered noise levels from that of conventional UH-60s. It also had low-observable technology similar to that ofF-117that enabled it to evadePakistan Air Forceradars. The aircraft seemed to include features like special high-tech materials, harsh angles, and flat surfaces, found only on sophisticated stealth jets. This came to light only when one of the helicopters used in the operation crashed and was subsequently destroyed except for its tail section.[17][18][Nb 1][19]Low observable versions of the Black Hawk have been studied as far back as the mid-1970s.[20]In September 2012, Sikorsky was awarded a Combat Tempered Platform Demonstration (CTPD) contract to further improve the Black Hawk's durability and survivability. Sikorsky is to develop new technologies such as a zero-vibration system, adaptive flight control laws, advanced fire management, a more durable main rotor, full-spectrum crashworthiness, and damage tolerant airframe, then transition them to the helicopter. Improvements to the Black Hawk are to continue in preparation for theFuture Vertical Liftprogram that is to replace it.[21][22]Design[edit]

UH-60A Black Hawk parked on flight lineThe UH-60 features four-blade main and tail rotors, and is powered by twoGeneral Electric T700turboshaftengines.[23]The main rotor is fully articulated and haselastomericbearings in the rotor head. The tail rotor is canted and features a rigid crossbeam.[24]The helicopter has a long, low profile shape to meet the Army's requirement for transporting aboard aC-130 Hercules, with some disassembly.[23]It can carry 11 troops with equipment, lift 2,600lb (1,170kg) of cargo internally or 9,000lb (4,050kg) of cargo (for UH-60L/M) externally by sling.[15]The Black Hawk helicopter series can perform a wide array of missions, including the tactical transport of troops, electronic warfare, and aeromedical evacuation. AVIPversion known as the VH-60N is used to transport important government officials (e.g., Congress, Executive departments) with the helicopter's call sign of "Marine One" when transporting thePresident of the United States.[25]Inair assaultoperations it can move a squad of 11 combat troops or reposition a 105mmM119 howitzerwith 30 rounds ammunition, and a four-man crew in a single lift.[15]The Black Hawk is equipped with advanced avionics and electronics for increased survivability and capability, such as theGlobal Positioning System.

A view of a UH-60 cockpitThe UH-60 can be equipped with stub wings at top of fuselage to carryfuel tanksor various armaments. The initial stub wing system is calledExternal Stores Support System(ESSS).[26]It has two pylons on each wing to carry two 230USgal (870L) and two 450USgal (1,700L) tanks in total.[11]The four fuel tanks and associated lines and valves form the external extended range fuel system (ERFS).[27]U.S. Army UH-60s have had their ESSS modified into the crashworthy external fuel system (CEFS) configuration, replacing the older tanks with up to four total 200USgal (760L) crashworthy tanks along with self-sealing fuel lines.[28]The ESSS can also carry 10,000lb (4,500kg) of armament such as rockets, missiles and gun pods.[11][29]The ESSS entered service in 1986. However it was found that with four fuel tanks it would obstruct the firing field of the door guns. To alleviate the issue, the external tank system (ETS) with unswept stub wings t