Sikorsky CH-53E Super Stallion
The Sikorsky CH-53E Super Stallion is a heavy lift helicopter operated by the United States military. As the Sikorsky S-80, it was developed from the CH-53 Sea Stallion, mainly by adding a third engine, adding a seventh blade to the main rotor, and canting the tail rotor 20°. It was built by Sikorsky Aircraft for the United States Marine Corps. Developed in the 1970s, it entered service in 1981, and is planned to be in service into the 2030s. It is one of the largest military helicopters in service, and is operated from U.S. Navy ships or from land.
The Navy also operates the MH-53E Sea Dragon which fills the United States Navy's need for long-range minesweeping or airborne mine countermeasures missions, and performs heavy-lift duties for the Navy. The Sikorsky CH-53K King Stallion, which has new engines, new composite rotor blades, and a wider aircraft cabin, is set to replace the CH-53E and enter service in the 2020s. Most of the Super Stallions in service are configured as MH-53E Sea Dragons.
Development
Background
The CH-53 was the product of the U.S. Marines' "Heavy Helicopter Experimental" competition begun in 1962. Sikorsky's S-65 was selected over Boeing Vertol's modified CH-47 Chinook version. The prototype YCH-53A first flew on 14 October 1964. The helicopter was designated "CH-53A Sea Stallion" and delivery of production helicopters began in 1966. The first CH-53As were powered by two General Electric T64-GE-6 turboshaft engines with 2,850 shp and had a maximum gross weight of 46,000 lb, including 20,000 lb in the payload.Variants of the original CH-53A Sea Stallion include the RH-53A/D, HH-53B/C, CH-53D, CH-53G, and MH-53H/J/M. The RH-53A and RH-53D were used by the US Navy for minesweeping. The CH-53D included a more powerful version of the General Electric T64 engine, used in all H-53 variants, and external fuel tanks. The CH-53G was a version of the CH-53D produced in West Germany for the German Army.
The U.S. Air Force's HH-53B/C "Super Jolly Green Giant" was for special operations and combat rescue, and was first deployed during the Vietnam War. The Air Force's MH-53H/J/M Pave Low helicopters were the last of the twin-engined H-53s and were equipped with extensive avionics upgrades for all-weather operation.
H-53E
In October 1967, the US Marine Corps issued a requirement for a helicopter with a lifting capacity 1.8 times that of the CH-53D that would fit on amphibious warfare ships. The US Navy and US Army were also seeking similar helicopters at the time. Before the issue of the requirement, Sikorsky had been working on an enhancement to the CH-53D, under the company designation "S-80", featuring a third turboshaft engine and a more powerful rotor system. Sikorsky proposed the S-80 design to the Marines in 1968. The Marines liked the idea, since it promised to deliver a good solution quickly, and funded the development of a testbed helicopter for evaluation.In 1970, against pressure by the US Defense Secretary to take the Boeing Vertol XCH-62 being developed for the Army, the Navy and Marines were able to show the Army's helicopter was too large to operate on landing ships and were allowed to pursue their helicopter. Prototype testing investigated the addition of a third engine and a larger rotor system with a seventh blade in the early 1970s. In 1974, the initial YCH-53E first flew.
Changes on the CH-53E also include a stronger transmission and a fuselage stretched. The main rotor blades were changed to a titanium-fiberglass composite. The tail configuration was also changed. The low-mounted, symmetrical, horizontal tail was replaced by a larger, vertical tail, and the tail rotor tilted from the vertical to provide some lift in hover while counteracting the main rotor torque. Also added was a new automatic flight control system. The digital flight control system prevented the pilot from overstressing the aircraft.
YCH-53E testing showed that it could lift , and without an external load, could reach at a gross weight. This led to two preproduction aircraft and a static test article being ordered. At this time, the tail was redesigned to include a high-mounted, horizontal surface opposite the rotor with an inboard section perpendicular to the tail rotor then at the strut connection cants 20° to horizontal. This helps with a tilt at high speed.
The initial production contract was awarded in 1978, and service introduction followed in February 1981. The first production CH-53E flew in December 1980. The US Navy acquired the CH-53E in small numbers for shipboard resupply. The Marines and Navy acquired a total of 177.
The base-model CH-53E serves both the US Navy and Marines in the heavy-lift transport role. It is capable of lifting heavy equipment, including the eight-wheeled LAV-25 light armored vehicle and the M198 155 mm Howitzer with ammunition and crew. The Super Stallion can recover aircraft up to its size, which includes all Marine Corps aircraft except for the KC-130.
By 2017, the CH-53E reportedly required 40 maintenance hours per flight hour due to aging parts, lack of available new replacement parts, and the extension of the overall airframe lifetime.
MH-53E
The Navy requested a version of the CH-53E for the airborne mine countermeasures role, designated "MH-53E Sea Dragon". It has enlarged sponsons to provide substantially greater fuel storage and endurance. It also retained the in-flight refueling probe and could be fitted with up to seven 300-US-gallon ferry tanks internally. The MH-53E digital flight-control system includes features specifically designed to help tow minesweeping gear. The prototype MH-53E made its first flight on 23 December 1981. MH-53E was used by the Navy beginning in 1986. The MH-53E is capable of in-flight refueling and can be refueled at hover. The MH-53E Sea Dragon is also used for heavy vertical delivery. The Helicopters are still in service as of the 2020s.Additionally, 11 MH-53E helicopters were exported to Japan as the S-80-M-1 for the Japan Maritime Self-Defense Force, deliveries starting in 1989.
The MH-53E is tasked with mine hunting, sweeping, clearing, and can use specialized equipment such as towed rigs. With the helicopter's heavy lift abilities, it can also be used for ship-to-shore transport and vertical on-board delivery.
CH-53K
The US Marine Corps had been planning to upgrade most of their CH-53Es to keep them in service, but this plan stalled. Sikorsky then proposed a new version, originally the "CH-53X", and in April 2006, the USMC signed a contract for 156 aircraft as the "CH-53K". The Marines planned to start retiring CH-53Es in 2009 and needed new helicopters quickly. In August 2007, the USMC increased its CH-53K order to 227 helicopters. Their first flight was planned for November 2011. On 4 December 2012, Sikorsky delivered the first CH-53K, a Ground Test Vehicle airframe.The United States Marine Corps plans to receive 200 helicopters at a total cost of $25 billion. Ground Test Vehicle testing started in April 2014; flight testing began with the maiden flight on 27 October 2015. In May 2018, the first CH-53K was delivered to the Marine Corps.
The U.S. Marine Corps received its first CH-53K simulator at Marine Corps Air Station New River in Jacksonville, North Carolina, on 1 May 2020. It is a Containerized Flight Training Device built by Lockheed Martin, Sikorsky's parent company.
On 22 April 2022, Lt. General Mark R. Wise, Deputy Commandant for Aviation, declared initial operational capability for the CH-53K. By February 2023, nearly 20 CH-53K King Stallions have been produced.
Design
Although dimensionally similar, the three-engined CH-53E Super Stallion is a much more powerful aircraft than the original Sikorsky S-65 twin-engined CH-53A Sea Stallion. The CH-53E also added a larger main rotor system with a seventh blade.The CH-53E was designed for transporting up to 55 troops with the installation of seats along the cabin center line or of cargo, and can carry externally slung loads up to. The CH-53E has incorporated the same crash-attenuating seats as the MV-22B to increase the survivability of passengers, but reduced its troop transport capacity to 30. The Super Stallion has a cruise speed of 173 mph and a range of 621 miles. The helicopter is fitted with a forward-extendable in-flight refueling probe. It can carry three machine guns, one at the starboard side crew door; one at the port window, just behind the copilot; and a firing position on the tail ramp. The CH-53E also has chaff-flare dispensers.
The MH-53E features enlarged side-mounted fuel sponsons, and is rigged for towing various minesweeping and hunting gear from above the dangerous naval mines. The Sea Dragon can be equipped for minesweeping and cargo and passenger transportation. Its digital flight-control system includes features specifically designed to help towing minesweeping gear.
In addition, the CH-53E has been upgraded to include the helicopter night vision system, improved.50 BMG GAU-21/A and M3P machine guns, and AAQ-29A forward-looking infrared imager.
The CH-53E and the MH-53E were the largest helicopters in the Western world until the introduction of the CH-53K. They rank behind the Russian Mil Mi-26 Halo, which remains the world’s heaviest-lifting helicopter in production with a payload capacity of up to 20 tonnes, and the Mil V-12 Homer prototype, which achieved record lifts of more than 44 tonnes. They are also preceded by the earlier Mil Mi-6, which despite a smaller payload capacity of about 12 tonnes had a maximum takeoff weight of 42 tonnes. Another heavy-lift helicopter family is the CH-47 Chinook, which has a twin-tandem rotor configuration and two engines, but is smaller than the Ch-53E Super Stallion.
In comparison of the largest lifting helicopters include the Mil Mi-26 has a maximum takeoff weight of 56,000 kg and can lift up to 20,000 kg externally, the King Stallion which has a MTOW of 38,600 kg and can lift up to 16,329 kg externally, the Mil-10, with and MTOW of 28,200 kg and can lift up to 12,000 kg, the Chinook, at 22,680 kg and can lift up to 9,000 kg externally, and Mi-6, at 42,000 kg and can lift up to 12,000 kg, the Eurocopter AS332 Super Puma can lift 9,800 kg and can lift up to 4,800 kg externally.