Tag Archives: Sikorsky a Lockheed Martin Company

13 March 1977

March 13, 2025Aviation76002, Allison 250-C30, First Flight, John Dixson, N762SA, Nicholas D. Lappos, Prototype, Sikorsky a Lockheed Martin Company, Sikorsky Aircraft Corporation, Sikorsky S-76ABryan Swopes

13 March 1977: The protoype Sikorsky S-76A Spirit made its first flight at the company’s Development Flight Center, West Palm Beach, Florida (06FA). This was the number two aircraft, serial number 76002, registered N762SA. Sikorky’s chief pilot, John Dixson, and S-76 program test pilot Nicholas D. Lappos were in the cockpit.

Test pilot Nick Lappos is congratulated following teh first flight of the Sikorsky S-76, 13 March 1977. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers) — Test pilot Nick Lappos is congratulated by His Majesty King Hussein bin Talal of Jordan following the first flight of the Sikorsky S-76, 13 March 1977. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)

The prototype was rolled out 11 January 1977.

The Sikorsky S-76 is a twin-engine medium helicopter designed to carry up to 12 passengers 400 nautical miles (460.3 statute miles, 740.8 kilometers) for the offshore oil industry. It is flown by two pilots and is certified for instrument flight. The helicopter can be configured to carry up to thirteen passengers.

The S-76 is used as a passenger transport, executive or VIP aircraft, and in law enforcement, search and rescue, or military service. It is also widely used as a medical transport helicopter.

Prototype Sikorsky S-76A rollout, 11 January 1977. (Sikorsky Historical Archives)

In 1979, Sikorsky proposed the new helicopter for consideration as the U.S. Coast Guard Short Range Recovery Helicopter, along with competitors Aérospatiale and Bell Helicopter. The S-76 was considered to be the most suitable of the three but the company made a business decision to withdraw before any contract was awarded. The Aérospatiale SA-365 Dauphin variant was finally selected and became the MH-65 Dolphin.

Air Logistics accepted the first Sikorsky S-76A production helicopter 27 February 1979. (Sikorsky, a Lockheed Martin Company) — Air Logistics accepted the first Sikorsky S-76A production helicopter, 27 February 1979. (Sikorsky, a Lockheed Martin Company)

The S-76A has an overall length of 52 feet, 6 inches (16.002 meters) with rotors turning, and overall height of 14 feet, 6 inches (4.420 meters). It had an empty weight of 7,132 pounds (3,235 kilograms) and a maximum gross weight of 10,500 pounds (4,763 kilograms).

The four-bladed, fully-articulated main rotor has a diameter of 44 feet, 0 inches (13.411 meters). The main rotor hub is constructed of forged aluminum and uses elastomeric bearings to allow for blade flapping and lead-lag. The blades are made of composite materials formed around a hollow titanium spar. The blade tips are swept to reduce the formation of blade tip vortices. Each blade is 19 feet, 11¾ inches long (6.090 meters). The main rotor turns counter-clockwise, as seen from above. (The advancing blade is on the right.) At 107% NR, the maximum speed with power on, the rotor turns 313 r.p.m.

A four-bladed tail rotor with a diameter of 8 feet, 0 inches (2.438 meters) is mounted on the left side of a pylon in a pusher configuration. The tail rotor turns clockwise as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.)

A Turboméca-powered Sikorsky S-76C in flight over the City of New York. (Sikorsky, a Lockheed Martin Company)

The S-76A was originally powered by two Allison 250-C30 turboshaft engines mounted side-by-side, behind the main transmission. The engines were rated at 557 shaft horsepower (maximum continuous power). 100% torque is 564 foot-pounds. Later production models have used Turboméca and Pratt & Whitney Canada engines.

The S-76A has a cruise speed and maximum speed (V_NE) of 155 knots (178 miles per hour/287 kilometers per hour). (The helicopter’s cruise speed is the same as its maximum.) The service ceiling is 15,000 feet (4,572 meters). The maximum altitude for takeoff and landing is 6,900 feet (2,103 meters).

Over a five-day period, 4–9 February 1982, Sikorsky test pilots Nicholas D. Lappos, William Frederick Kramer, Byron Graham, Jr., David R. Wright, and Thomas F. Doyle, Jr., set a series of twelve Fédération Aéronautique Internationale (FAI) speed, time-to-climb and sustained altitude world records while flying a Sikorsky S-76A helicopter, N5445J, at Palm Beach, Florida. These included an absolute world speed record for helicopters (186.69 knots/214.83 miles per hour/345,74 kilometers per hour). Nine of these records remain current.¹

In April 2020, new FAA regulations requiring crash-resistant fuel tanks for new-production aircraft took effect. Lockheed Martin decided not to invest in the engineering required to update the S-76. As such, the helicopter was no longer allowed to be sold in the United States. New Sikorsky S-76Ds continued to be sold to overseas customers. Later in the year, though, production came to an end.

876 Sikorsky S-76 were built. There were 307 S-76A and S-76A+ variants produced, followed by the S-76B, S-76C, -C+ and -C++. The final production model was the S-76D.

Sikorsky S-76D N7621Y, c/n 761021. (Sikorsky, a Lockheed Martin Company)

¹ See “This Day in Aviation” https://www.thisdayinaviation.com/4-february-1982/

27 October 2015

October 27, 2024AviationBu. No. 169019, EDM-1, First Flight, General Electric GE38-1B, Prototype, Sikorsky a Lockheed Martin Company, Sikorsky Aircraft Corporation, Sikorsky CH-53K King Stallion, Sikorsky S-95, Stephen McCulley, T408-GE-400, Test PilotBryan Swopes

27 October 2015: The first flight of the Sikorsky CH-53K King Stallion Engineering Development Model–1, Bu. No. 169019, at West Palm Beach, Florida. In the cockpit was Stephen McCulley, Chief Experimental Test Pilot for Sikorsky. During the 30 minute flight, the new helicopter demonstrated sideward, rearward and forward flight while remaining in in-ground-effect hover.

Up to this point, the helicopter had completed about 200 hours of “turn-time,” or ground testing, with engines running..

Three more aircraft will join the test fleet for a planned 2,000 hour flight test program.

The CH-53K King Stallion test fleet. (Sikorsky, a Lockheed Martin Company)

The fuselage of the CH-53K King Stallion is 73 feet, 1.5 inches (22.289 meters) long and its width is 9 feet, 10 inches (2.997 meters). The maximum width, across the sponsons, is 17 feet, 6 inches (5.334 meters). The seven-bladed main rotor has a diameter of 79 feet (24.079 meters). The four-blade tail rotor is 20 feet (6.096 meters) in diameter. The tail rotor is tilted 20° to the left. With rotors turning, the helicopter has an overall length of 99 feet (30.175 meters), and height of 28 feet, 4.9 inches (8.659 meters). The helicopter’s maximum gross weight is 88,000 pounds (39,916 kilograms).

Power is supplied by three General Electric T408-GE-400 engines which produce 7,500 shaft horsepower, each. The engine has digital electronic controls. The T408 has a 6-stage compressor section (5 axial-flow stages, 1 centrifugal-flow stage) and 5 stage turbine section (2 high- and 3 low-pressure stages). The engine is 57.5 inches (1.461 meters) long and 27 inches (0.686 meters) in diameters.

At Sea Level with maximum continuous power, the CH-53K cruises at 158 knots (182 miles per hour/293 kilometers per hour). It can hover out of ground effect at Sea Level at its maximum gross weight. The helicopter’s service ceiling is 16,000 feet (4,877 meters).

The first production CH-53K was delivered to the U.S. Marine Corps on 16 May 2018, at West Palm Beach, Florida.

Sikorsky delivered the first of 200 CH-53K King Stallion Helicopters to the USMC from West Palm Beach, Florida, on May 16. Image courtesy of U.S. Marine Corps. (PRNewsfoto/Lockheed Martin)

14 September 1939

September 14, 2024AviationFirst Flight, Helicopter, Igor Ivanovich Sikorsky, Lycoming O-145-C3, Prototype, Sikorsky a Lockheed Martin Company, Vought-Sikorsky Aircraft Division, Vought-Sikorsky VS-300Bryan Swopes

14 September 1939: At Stratford, Connecticut, Igor Sikorsky made the first tethered flight of the Vought-Sikorsky VS-300 prototype helicopter. The duration of the flight was just 10 seconds but demonstrated that the helicopter could be controlled.

The Vought-Sikorsky VS-300 was the first successful single main rotor, single tail rotor helicopter.

The three-bladed main rotor had a diameter of 28 feet (8.534 meters) and turned approximately 255 r.p.m. The rotor turned clockwise as seen from above (the advancing blade is on the left). This would later be reversed. A counter-weighted single blade anti-torque rotor with a length of 3 feet, 4 inches (1.016 meters) is mounted on the left side of the monocoque beam tail boom in a pusher configuration and turns counter-clockwise as seen from the helicopter’s left (the advancing blade is above the axis of rotation).

Vought-Sikorsky VS-300 under construction, 8 September 1939. (Sikorsky Historical Archives)

In the initial configuration, the VS-300 was powered by an air-cooled, normally-aspirated, 144.489-cubic-inch-displacement (2.368 liter) Lycoming O-145-C3 horizontally-opposed, four-cylinder, direct-drive engine with a compression ratio of 6.5:1. It was rated at 75 horsepower at 3,100 r.p.m., using 73-octane gasoline. It was equipped with a single Stromberg carburetor and dual Scintilla magnetos. The dry weight of the O-145-C3 was 167 pounds (75.75 kilograms). Later in the VS-300’s development, the Lycoming was replaced by a 90-horsepower Franklin 4AC-199 engine.

On 19 December 1939, the VS-300 was rolled over by a gust of wind and damaged. It was rebuilt, however, and developed through a series of configurations. It made its first free (untethered) flight 13 May 1940.

Test flights continued for several years. After 102 hours, 32 minutes, 26 seconds of flight, the VS-300 was donated to the Henry Ford Museum, Dearborn, Michigan.

Igor Sikorsky adjusts is fedora while at teh controls of the VS-300. (Sikorsky Historical Archives) — Igor Sikorsky adjusts his fedora while at the controls of the VS-300. (Sikorsky Historical Archives)