The H-53 Pave Low, still widely known by its Vietnam-era nickname 'Super Jolly' is the USAF's largest and most powerful helicopter. The USAF operates the TH-53A for type training and the MH-53J Enhanced Pave Low III version for special operations and combat rescue.

The H-53 is a conventional, long-range helicopter with twin turboshaft engines and self-lubricating, all-metal main and tail rotors. A large horizontal stabilizer is on the starboard side of the rotor pylon. The tricycle landing gear has twin wheels on each unit, with the main units retracting into the rear of the sponsons on each side of the fuselage. The helicopter is equipped with inflight-refueling probe, two 315-US gal (1,192-liter) self-sealing bladder-type fuel tanks, and two 450-US gal (1,703-liter) external auxiliary fuel tanks. The helicopter ordinarily has a flight crew of two pilots and navigator, plus two pararescue technicians (PJs) for rescue and special operations work.

For conventional operations, itr can transport 38 combat-equipped troops on side-facing seats or 22 litter patients and four medical attendants, or 18,500 lb (8,391 kg) of freight.

Current missions assigned to the MH-53J reflect the increased emphasis on special operations in the USAF Special Operations Command. Formed in March 1990, AFSOC employs the aircraft to penetrate enemy territory in support of Special Forces, Delta Force and SEAL teams operating in denied areas, or for combat rescue of friendly personnel. For these missions, the MH-53J is armed with 7.62-mm (0.3-in) Miniguns operated by the PJ, whose duties have been expanded to include behind-the-lines work. MH-53Js are routinely made available for peacetime SAR (search and rescue) emergencies in both the military and civilian worlds.

The MH-53J has multi-mode radar for terrain following and terrain avoidance, FLIR, additional titanium armor plating, and increased fuel capacity. It is powered by two 4,380-shp General Electric T64-GE-415 turboshaft engines driving a five-bladed, 72-ft 3-in (22.02-m) main rotor.

The H-53 series began with the first flight of a US Marine Corps YCH-53A prototype on 14 October 1964, and with May 1966 deliveries of the CH-53A to the Marines. Six ex-Marine A models were transferred as TH-53A basic qualification trainers to the USAF's 542nd Crew Training Wing, Kirtland AFB, New Mexico, the RTU (replacement training unit) for the type (since redesignated 58th SOW. Versions of the helicopter are used by the US Marine Corps (CH-53A, CH-53D, VH-53D, CH-53E), US Navy (RH-53A, MH-53A, RH-53D, MH-53D, YCH-53E, MH-53E), Israel (CH-53D), and Germany (CH-53G). Other foreign variants include the S-65C-2 (Austria) and S-80M-1 (Japan).

Development of a USAF combat rescue model of the helicopter began on 28 November 1966 when the first of two Marine CH-53As was loaned to the Air Force. Eight USAF combat-rescue HH-53Bs (66-14428/14435) followed, first flying on 15 March 1967 and becoming operational by June 1967. The HH-53B replaced the HH-3E in Vietnam, acquiring its adaptation of the latter's nickname, 'Jolly Green Giant'. One HH-53B was tested in 1969 with a night/all-weather rescue system known as Pave Low I, which did not prove successful.

Twenty CH-53Cs were delivered, these being transport versions lacking the air-refueling probe found on rescue helicopters. The CH-53C was initially employed for covert operations; later, eight CH-53Cs were used to provide battlefield mobility for the USAF Mobile Tactical Air Control System.

The 44 upgraded HH-53C combat-rescue helicopters also served in Vietnam, from 1969 on. These aircraft participated in the attempt to rescue American prisoners of war in the celebrated Son Tay raid of November 1970. The HH-53C remained in service into the late 1980s. HH-53Cs supported Apollo space missions because their external cargo hook of 20,000-lb (9,072-kg) capacity would have enabled them to retrieve the manned lunar capsule in the event of an abort just after launch.

The designation VH-53F was assigned to six aircraft ordered for the Air Force but with US Navy bureau numbers (159123/159128) for VIP transport by the 89th Military Airlift Wing. These were cancelled before deliveries could take place. The sole YHH-53H, a former HH-53B (66-14433), tested a night/all-weather system dubbed Pave Low II, which served as a proof-of-concept vehicle for HH-53H and MH-53J Pave Low III variants to follow.

The HH-53H Pave Low III was a USAF rebuild of two CH-53Cs and eight HH-53B/Cs with night/all-weather search and rescue equipment including inertial navigation system, Doppler, projected map display, AN/AAQ-10 infra-red and AN/APQ-158 terrain-following radar in a thimble fairing offset to port on the nose. The HH-53H modification was found to increase the maintenance demands of the type, a problem rectified in the subsequent J model. HH-53H aircraft were redesignated MH-53H in 1986 when upgraded for the special operations mission under the Constant Green program. The MH-53H was the first version to be fully cleared for nocturnal operations with the crew employing NVG (night vision goggles).

The decision to upgrade the USAF's H-53 fleet (including seven CH-53Cs) to MH-53J Enhanced Pave Low III standard was partly the result of poor performance by Navy RH-53D helicopters during the attempted rescue of American hostages in Iran in April 1980 and by less than full satisfaction with the HH-53H version. The MH-53J is intended to launch from a variety of environments, including ship decks, and includes folding rotors for storage aboard aircraft carriers and assault ships. The MH-53J introduces the -415 version of the T64 turboshaft engine, some 1,000 lb (454 kg) of additional titanium armor, and gross weight increased from 42,000 lb (19,050 kg) to 50,000 lb (22,680 kg). The first MH-53J was delivered on 17 July 1987. The J model entered service at Hurlburt Field, Florida, in 1988.

During Operation Just Cause in Panama, the MH-53J Pave Low III dropped US Navy SEAL commandos who assaulted Panama City's Patilla Airport to destroy a Lear Jet which might otherwise have been used to assist the escape of Panamanian leader Manuel Noriega. In March 1990, MH-53Js were transferred to USAF Special Operations Command. During Operation Desert Storm, MH-53Js provided navigation and support for the US Army AH-64 Apaches which attacked Iraqi radar defense sites during the first attack of the war. During the war with Iraq, special operations MH-53Js inserted American and British commandos behind the lines including some who scouted Iraqi 'Scud' missile sites. They also rescued a down US Navy F-14 Tomcat pilot.

In the future, the USAF hopes to replace its MH-53J fleet and several other types with some 55 Bell/Boeing V-22 Osprey tilt-rotor special operations aircraft. However, the MH-53J fleet, which has no structural fatigue problems, is likely to remain in service through the end of the century.