Sikorsky

Sikorsky VS-300

Being technical director of the Vought-Sikorsky Aircraft Corporation, Igor Sikorsky started in spring 1939 to design a helicopter with a three-bladed main rotor and 3 anti-torque propellers mounted on a tail boom. The aircraft made its first flight on 14 September, 1939, however, it only rose a short distance from the ground. In November 1939, the duration of the flights was extended to 2 minutes. Several men tethered the helicopter on the ground so that it could not accidentally escape. The first free flight was on 13 May, 1940. In summer of the same year, flights with a duration of 15 minutes were accomplished. On 6 May, 1941, Sikorsky flew for 1h 32min 26s, a new endurance record. Thanks to further modifications, the flight and control characteristics of the VS-300 had been so much improved that in June 1941, Sikorsky could present the machine to the public. During his presentations he liked to entertain the crowds: On all his flights he wore a fedora that was to become his trademark. Hovering just above the ground, he asked his assistant to deposit a parcel in a basket or to change a wheel. The significant technical achievement was the single-rotor design with an anti-torque rotor mounted at the tail, which has become the typical feature of every Sikorsky helicopter. In its second version the helicopter had a triangular open-grid tail boom. It also incorporated a more powerful engine (with 110 instead of 95 kW). With a flight time of 1h 32min the helicopter bet the record of 1h 20 min held by the FW-61.

VS-300 Version 1

The main-rotor mast with main-rotor head of the VS-300

The VS-300 Version 2 with three tail rotors

VS-300 Version 2

VS-300 Version 2

Final form, the VS-300 Version 4

Sikorsky R-4

Owing to Sikorsky’s success with the VS-300, the US Air Force initiated the further development of a helicopter twice as large and with twice as much engine power. A prototype was ordered with the designation XR-4. It also had a single-engine design, but with a covered fuselage and a fully-enclosed cabin, side-by-side seating and dual controls. The flying control set standards for all subsequent helicopters until today. The first flight was made on 14 January, 1942. In 1943, the prototype XR-4C was equipped with a more powerful engine and rotor blades extended by 60 cm. The R-4 was in service in the US Navy, the US Air Force (also called VS-316 or HNS-1 "Hoverfly I") and the Coast Guard (23), as well as in the British Royal Air Force (52) and the Royal New Zealand Air Force. This helicopter was the first serial-production helicopter in the United States. The XR-4 was followed by 3 YR-4A, 27 YR-4B and 100 R-4B.

Sikorsky S-70 A (UH-60A Black Hawk)

Designed for the Utility Tactical Transport Aircraft System (UTTAS), the Sikorsky S-70 was intended as a replacement for the Bell UH-1. It had to capable of carrying 11-man infantry troops and its equipment. The first machine had its first flight on 17 October, 1974, as a prototype and was selected as the winner of the design competition. The first serial contract covered 15 UH-60A Black Hawk helicopters, a further 368 were the subject of a fixed-price option. In April 1982, another contract covered 294 machines more for delivery up to 1985. Powered by two 1,560 shp (1,163 kW) General Electric T700-GE-700 shaft turbines, the UH-60A can carry external loads such as Hellfire missiles and long-range fuel tanks as well as M60 machine guns in the forward area of the cabin firing from beside the helicopter. The United States Air Force ordered nine UH-60A to serve as rescue helicopters with the 55th ARRS at Eglin AFB, and on 24 September, 1981, the YEH-60A, a version equipped for electronic countermeasures, had its first flight.

The USAF also ordered two UH-60A to be converted within the framework of the HH-60D Night Hawk programme. This was an all-weather helicopter with a rescue winch, auxiliary tanks, an air-to-air refuelling probe, improved avionics and with enhanced 1,690-shp (1,261-kW) 7700-GE-401 engines. The HH-60A is a Night Hawk with limited potential, without Forward-Looking Infrared Radar (FLIR) and even without Terrain-Following Radar (TFR). When the LAMPS (Light Airborne Multi-Purpose System) programme required a helicopter with a larger capacity than that of the Kaman Seasprite that won the LAMPS Mk 1 order, significant economies could be achieved from selecting the marine version S-70L, the SH-60B Seahawk, due to substantial commonality with the UH-60A. This version has a surveillance radar mounted under the nose, ESM (electronic support measures) equipment, a pylon for carrying MAD (magnetic anomaly detection) equipment on the starboard side, a sonobuoy launcher, an automatic rotor-folding system, a foldable tail pylon and a modified landing gear. Mk 46 torpedos are part of this armament for anti-submarine and anti-vessel operation with observation and target-acquisition function. The first of five prototypes flew on 12 December, 1979, followed by the first serial aircraft on 11 February, 1983. Initial deliveries were made on 24 March, 1983. The first US Navy unit to use the helicopter was HSL-41 at North Island, San Diego, California. The SH-60B operates from frigates and destroyers, while the SH-60F version derived from the SH-60B has replaced the SH-3H Sea King. The Sikorsky S-70C is the civil version of the Black Hawk derived from the H-60 series and equipped with two General Electric CT7-2C shaft turbines. The People’s Republic of China ordered 24 aircraft, the first nine of which were delivered in 1985.

Type designation:	S-70A (UH-60A Black Hawk)
Usage:	Medium-sized transport helicopter
Year of construction:	Serial production since 1977
Manufacturer:	Sikorsky
Country:	USA
First flight:	17.10.1974
Length:	15,26 m
Width:
Height:	5,13 m
Rotor diameter:	16,36 m
Number of rotor blades:	4
Powerplant:	2x General Electric T700-GE-700
Power:	1560 hp
Max. speed:	296 km/h
Service ceiling:	5840 m
Empty weight:	5118 kg
Max. take-off weight:	9979 kg
Range:	600 km
Crew:	3
Passengers:	14 or 6 stretchers and 3 persons
Armament:	n/a
Manufactured:	4 prototypes / 1650 being built

Sikorsky S-80 / CH-53E / MH-53E / YCH-53E

Specifications

Version		CH-53E S-80E	MH-53E S-80M
Dimensions
Overall length	m	30,20	30,20
Overall height	m	8,60	8,60
Fuselage length	m	18,40	18,40
Main rotor diameter	m	24,10	24,10
Tail rotor diameter	m	6,10	6,10
Masses
Max. take-off mass	kg	33339	33339
Empty mass	kg	15073	16611
Powerplant
Turbines		General Electric T64-GE-416A	General Electric T64-GE-419
Turbine power	shp	3702 each	4230 each
Flight performance and limits
Max. speed	km/h	315	315
Max. cruise speed	km/h	278	278
Max. climb rate	m/s	12,7	12,7
Max. range	km
Max. endurance	h
Hover ceiling (IGE)	m
Max. hover ceiling (OGE)	m