Sikorsky H-60/S-70 Black Hawk
9th June 2021Sikorsky H-60/S-70 Black Hawk user+1@localho Wed, 06/09/2021 - 21:17
The Sikorsky H-60 Black Hawk is a medium weight military transport helicopter in service with the U.S. Air Force, Army, Marine Corps, Navy and Coast Guard, and with dozens of military operators in Europe, Asia, Latin America, the Middle East and Africa. More than 4,000 Black Hawks have been built since 1974. U.S. and Foreign Military Sales (FMS) Black Hawks are designated as H-60s with subvariants, such as the UH-60, MH-60, HH-60, etc., reflecting the primary mission the Black Hawk variant. Generally, Black Hawks sold via Direct Commercial Sale (DCS) are referred to as S-70s though Sikorsky does have internal designations for FMS Black Hawks as well.
During the Vietnam War, the Huey fleet proved the feasibility and utility of air mobile operations but suffered from a lack of survivability and insufficient cabin volume. The U.S. Army launched the Utility Tactical Transport Aircraft System (UTTAS) to replace the Huey in January 1972. The service planned to procure 1,107 helicopters which would be powered by two General Electric T700 engines. Early requirements for UTTAS included stowage within the C-130 and the ability to meet the following performance metrics on a 95 F day at 4,000 ft:
- accommodate a fully equipped rifle squad of 11 soldiers plus a crew of three
- cruise at a speed of at least 145 kts. (167 mph)
- endurance of 2.3 hrs.
- demonstrate greater crash resistance for crew compartments
- provide greater survivability against ground fire
Bell, Sikorsky, and Boeing- Vertol responded to the Army s UTTAS request for proposals (RFP). In August 1972, Boeing-Vertol and Sikorsky were selected to build prototypes for a competitive fly off with the YUH-60A and YUH-61A respectively. Each contract was to build three prototypes with $61.9 million for Boeing-Vertol and $91 million awarded to Boeing ($390 and $574 million in 2021 dollars respectively). Sikorsky was particularly deliberate in its bidding strategy. The company had begun work on its UTTAS concept in 1971 following the loss of both the Army's Advanced Aerial Fire Support System (AAFSS) and Heavy Lift Helicopter (HLH) competitions to Lockheed and Boeing-Vertol respectively.
Sikorsky s YUH-60A first took flight on Oct. 17, 1974 and was followed by Boeing-Vertol s design that November. The Army took delivery of contractor prototypes through March 1976 and subsequently began an eight-month evaluation encompassing more than 1400 flight hours. Sikorsky won source selection on December 23, 1976 owing to the type s use of mature technologies and to it meeting or exceeding all UTTAS program requirements. Following Army tradition, the UTTAS program was renamed as the Black Hawk program in honor of the eponymous Sauk war chief. See production & delivery section for more details.
Features & Variants
There are three generations of Black Hawks with successive improvements being made to each: H-60A, H-60L and H-60M. The Seahawk group is inter-related with each generation but is more often considered its own distinct group given its maritime focus.
The UH-60A was the first production configuration variant in the H-60 family with an initial empty weight of 10,387 lb. and a maximum take-off weight (MTOW) of 16,450 lb. The A model could accommodate external sling loads of up to 8,000 lb. As the A-model s mission equipment was expanded, its empty weight gradually increased to 11,284 lb. by the end of production. The UH-60A was initially powered by a pair of 1,600-shaft horsepower (SHP) T700-GE-700 turboshafts.
The UH-60A incorporated a host of new technologies and design features in its rotor arrangement to improve survivability and performance. The four-bladed main rotor uses titanium spars that are swept 20-deg. aft, while the tail rotor is canted 20-deg. upwards generating 400 lb. of supplemental lift. The UH-60A features armored, crash resistant crew seats and its airframe is designed to withstand small arms fire and to provide limited protection against 23 mm cannon fire.
Sikorsky has its own designation system independent of the U.S. tri-service system. For decades, each country had its own specific designation within the S-70A series. For example, Australia s aircraft, equivalent to the UH-60A, were designated as the S-70A-9. In contrast, Austrian aircraft were designated as the S-70A-42 but were equivalent to the UH-60L configuration. This system fell out of favor with the advent of the UH-60M-equivalent S-70i which does not receive a country specific identifier.
The MH-60A was the first UH-60 variant developed for U.S. Army Special Operations Command (USASOC) featuring SOF related mission systems such as night vision systems, improved countermeasures, and enhanced communications equipment. The aircraft was quickly replaced by the more capable MH-60K.
In the early 1980s, the Army briefly sought a helicopter to provide long-range, ground moving target indication (GMTI) capability. To this end, it experimented with a single YEH-60B demonstrator fitted with the Stand Off Target Acquisition System (SOTAS) radar starting in 1981. The system was fitted conformally to the bottom of the airframe and was deployed outwards, enabling the antenna to rotate. The Black Hawks inherent limitations in power, weight, and cooling capacity as well as in altitude (for signal propagation/horizon) made the helicopter ill-suited for long-range GMTI. Ultimately, the Army discontinued the program as the Northrop Grumman E-8 J-STARs became available.
The EH-60C is an electronic warfare variant of the Black Hawk fitted with the ALQ-151(V)2 Special Purpose Electronic Countermeasure System. The suite is also known as the Quick Fix mission system. The ALQ-151(V)2 consists of four dipole antennas mounted on the tailcone as well as a deployable whip antenna. EH-60Cs were used to support armored cavalry regiments and light divisions by locating and jamming enemy communications. These specialized aircraft were eventually replaced by EH-60Ls fitted with the ALQ-151(V)3.
The S-70C is a commercial version of the UH-60A. C-1 and C-1A models were sold the Republic of China (Taiwan) and C-2 to the People s Republic of China. See production & delivery history section for country specific modifications.
The VH-60N is a VIP transport variant operated by the Marine Corps HMX-1 the squadron responsible for the transport of the President and other key government officials. The N features a blend of Seahawk and A-model features. Aside from VIP furnishings, the N-model also features measures to protect the helicopter against electro-magnetic pulses.
UH-60A+ & UH-60FFF
The UH-60A+ features improved T700-GE-701D turboshafts capable of producing 2,000 SHP however, the A-model s gearbox remains unchanged. Surplus U.S. Army A-models were converted for Afghanistan. A portion of these are fitted with an armament package, becoming UH-60 Fixed Forward Firing (UH-60FFF) variants. See Afghanistan under production & delivery history section for additional details.
The second generation UH-60L was conceived to restore performance lost by increases to the A-model s empty weight. New mission equipment such as the Hover IR Suppression System (HIRSS) and provisions for the enhanced stores support system (ESSS) added approximately 900 lb. to the airframe. The L-model restored 1,000 lbs. of performance with the addition of a new 3,400 SHP gearbox derived from the SH-60B, T700-GE-701C engines which each provided 1,800 SHP and a new flight control system. The UH-60L can carry sling loads of 9,000 lb., enabling the helicopter to carry the High Mobility Multipurpose Wheeled Vehicle (HMMWV).
The CH-60E was a proposed UH-60L derivative for the USMC to replace the Boeing-Vertol CH-46 Sea Knight. While it was not pursued, the concept eventually evolved into the MH-60S.
HH-60G/MH-60G Pave Hawk
The Pave Hawk was developed for U.S. Air Force Special Operations Command (AFSOC). The MH-60G was used for special operations forces (SOF) infiltration and exfiltration while the HH-60G was developed for combat search and rescue (CSAR). To meet SOCOM s requirements, the aircraft recieved a series of modifications including an inflight refueling probe, a nose mounted weather radar, an automatic flight control system and measures to assist in all-weather operations.
The J model is a maritime SAR variant developed for the Japan Air Self Defense Force (JASDF) from the UH-60L. JASDF specific modifications include upswept ESSS mounts, a weather radar, a nose mounted FLIR, a rescue hoist and bubble windows for greater visual awareness during SAR. The J-model uses GE 401C engines which are adapted for maritime conditions. MSDF Black Hawks sport either a yellow-white or distinctive two-tone blue camouflage pattern.
The UH-60J or UH-60 J (modernized) (often referred to as or kai for modified when abbreviated or as UH-60J+ in English language sources) is a SAR variant fielded by the JASDF as a replacement for the J-model. The UH-60J+ configuration includes J-model features as well as a removable inflight refueling (IFR) probe, SATCOM and a collision avoidance system.
The UH-60JA is a general transport derivative based upon the UH-60L for the Japan Ground Self Defense Force (JGSDF). It features ESSS mounts, a nose mounted weather radar, a forward-looking infrared (FLIR) turret, IR suppressors and license built IHI 401C engines.
The K-model was developed for U.S. Army Special Operations Command (USASOC). The UH-60K features uprated T701D engines as well as additional longerons and strengthened structural components to raise the helicopter s MTOW to 24,500 lb. Mission equipment consisted of the Texas Instruments APG-174 terrain following radar (TFLR), the Raytheon AAQ-16 FLIR turret, and a digital map system. As with the Pave Hawk, the MH-60K featured an in-flight refueling probe and rescue hoist.
The Harpia is a gunship derivative of the Black Hawk developed by Colombia. Each successive generation of the Harpia added weapons and improved avionics. Early Harpia I models were limited to gun pods with 250 rounds of ammunition. Harpia II introduced stub pylon mounted hardpoints for machine guns and 2.75 in. rockets as well as a weather radar and night vision capability. Colombia partnered with Elbit and Sikorsky in 2002 to develop the Harpia III configuration which features a Toplite II FLIR and targeting system, the Modular Integrated Display and Sight Helmet (MiDASH), an integrated stores management system and an improved armaments package. Harpia IV features the ANVIS/HUD-24, Toplite III EO/IR system and an improved countermeasures suite.
The HH-60L is a medevac UH-60L derivative incorporating many of the preceding HH-60Q features including a glass cockpit, additional electrical power, an oxygen generating system and capacity for six patients.
The MH-60L Defensive Action Penetrator (DAP) which was originally named the Direct Action Penetrator shares the K-model s features but also is fitted with a weapons kit typically consisting of AGM-114 Hellfire missiles, M134 7.62 mm miniguns, 2.75-inch rocket pods or M230 30 mm cannons mounted on removable pylons. Despite carrying offensive weaponry comparable to that of an attack helicopter, the DAP lacks the armor protection of dedicated gunships.
The UH-60P is a UH-60L derivative for Korea with a rotor brake, ESSS mounts and T701C turboshaft engines.
The HH-60P is a Korean derivative of the UH-60P designed for CSAR missions. Unlike its USAF equivalent, the HH-60P does not have an IFR probe .
The VH-60P is a South Korean VIP variant derived from the UH-60P.
The HH-60Q Dustoff was a Medevac demonstrator featuring additional electrical power, an oxygen generating system and capacity for six patients. The Q-model also featured a nose mounted weather radar and FLIR system. Work on the Q-model informed the subsequent HH-60L.
The UH-60V is the latest derivative of the L model and features a digital cockpit similar to that of the UH-60M. The V-model features 2,000 SHP T701D turboshafts but lacks the new rotors and other performance enhancements developed for the M-model. See the production & delivery history section for additional details regarding the program.
As the load of equipment supplied to U.S. Army soldiers increased from 240 lb. to 290 lb., another revitalization of the Black Hawk was necessary to restore performance margins lost in the 1990s to early 2000s. The UH-60M s principal design changes include T701D turboshafts, new wide-chord composite rotor blades (which provide 470 lb. of additional lift), digital avionics, multi-function displays and a machined airframe to reduce vibration and weight. The M model has an empty weight of 12,511 lb. and MTOW of 22,000 lb.