Tag Archives: Sikorsky S-76A

13 March 1977

The number 2 Sikorsky S-76 makes teh type's first flight, 13 March 1977. (Sikorsky Historical Archives)
The number 2 Sikorsky S-76 prototype, s/n 76002, makes the type’s first flight, 13 March 1977. (Sikorsky Historical Archives)

13 March 1977: The Sikorsky S-76A Spirit prototype 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 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 Sikorsky S-76A 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.

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 withdrew 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). The S-76A 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. 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 Sikorsky S-76A in flight over the City of new York. (Sikorsky, a Lockheed Martin Company)
A Sikorsky S-76A 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 Turbomeca and Pratt & Whitney Canada engines.

The S-76A has a cruise speed and maximum speed (VNE) 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).

The Sikorsky S-76 remains in production, with more than 1,100 helicopters built. There were 307 S-76A and S-76A+ variants produced, followed by the S-76B, S-76C, -C+ and -C++. The current production model is the S-76D.

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

© 2017, Bryan R. Swopes

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4–9 February 1982

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

4–9 February 1982: Sikorsky test pilots Nicholas D. Lappos,  Byron Graham, Jr., David R. Wright, and Thomas F. Doyle, Jr., set a series of Fédération Aéronautique Internationale (FAI) speed, time-to-climb and sustained altitude world records while flying a Sikorsky S-76A helicopter, serial number 760178, FAA registration N5445J, at Palm Beach, Florida.

On 4 February, Nick Lappos, who had made the first flight with the prototype S-76, set a record of 208.470 miles per hour (335.50 kilometers per hour) over a 3-kilometer course, and 212.888 miles per hour (342.61 kilometers per hour) over a straight 15/25 kilometer course.

On 5 February, Byron Graham, Jr., flew the S-76A to 3,000 meters (9,842.52 feet) in 3 minutes, 11 seconds; to 6,000 meters (19,685.04 feet) in 8 minutes, 37.3 seconds; and a sustained altitude of 7,940 meters (26,049.87 feet) in level flight.

On 6 February David R. Wright averaged 205.881 miles per hour (331.22 kilometers per hour) over a 100 kilometer closed circuit without payload (Class E1d), and 207.967 miles per hour (334.69 kilometers per hour) over a closed circuit of 100 kilometers without payload (Class E1e).

After taking a day off, the Sikorsky S-76A was back in the air on 8 February, this time with Thomas F. Doyle, Jr., flying the helicopter over the 500 kilometer closed circuit without payload. The Sikorsky averaged 214.833 miles per hour (345.74 kilometers per hour).

On the last day of the series, 9 February 1982, David R. Wright was back in the cockpit of N5445J. Flying the 1,000 kilometer closed circuit without payload, the S-76A averaged 189.580 miles per hour (305.10 kilometers per hour).

After 34 years, these six Fédération Aéronautique Internationale world records still stand.

N5445J was owned by Rodgers Helicopter Service, Kearney, Nebraska, until its U.S. registration was cancelled, 10 July 2006.

Fire-damaged Sikorsky S-76A serial number 760178, registration PR-IME, at Macae Airport, Rio de Janeiro, Brasil, 29 December 2008.
Fire-damaged Sikorsky S-76A, serial number 760178, registration PR-IME, at Macaé Airport, Rio de Janeiro, Brasil, 29 December 2008.

The record-setting helicopter eventually found its way to Rio de Janeiro, Brazil. Owned and operated by Atlas Taxi Aereo, 760178 had been re-registered as PR-IME and was transporting Petrobras employees to offshore oil production platforms. At approximately 8:30 a.m., 29 December 2008, PR-IME had departed Macaé Airport enroute Platform P-12 in the Campos Basin with 7 persons on board. Shortly after takeoff, the flight crew observed an AC generator caution light and returned to the airport. Before landing, a fire warning light also illuminated. Upon landing on Runway 24, all seven escaped from the burning helicopter without injury. The fire was quickly extinguished, but the Sikorsky S-76A was substantially damaged.

FAI Record File Num #1261 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a straight 15/25 km course
Performance: 342.61 km/h
Date: 1982-02-04
Course/Location: Palm Beach, FL (USA)
Claimant Nicholas D. Lappos (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1262 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a 3 km course
Performance: 335.50 km/h
Date: 1982-02-04
Course/Location: Palm Beach, FL (USA)
Claimant Nicholas D. Lappos (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1819 [Direct Link]
Status: ratified – superseded since approved
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Time to climb to a height of 3 000 m
Performance: 3 min 11 sec
Date: 1982-02-05
Course/Location: Palm Beach, FL (USA)
Claimant Byron Graham Jr. (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1821 [Direct Link]
Status: ratified – superseded since approved
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Time to climb to a height of 6 000 m
Performance: 8 min 37.3 sec
Date: 1982-02-05
Course/Location: Palm Beach, FL (USA)
Claimant Byron Graham Jr. (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #9947 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Altitude in horizontal flight
Performance: 7 940 m
Date: 1982-02-05
Course/Location: Palm Beach, FL (USA)
Claimant Byron Graham Jr. (USA)
Rotorcraft: Sikorsky S-76
Engines: 2 Allison 250-C30

FAI Record File Num #1264 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1d (Helicopters: take off weight 1750 to 3000 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a closed circuit of 100 km without payload
Performance: 331.22 km/h
Date: 1982-02-06
Course/Location: Palm Beach, FL (USA)
Claimant David R. Wright (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1265 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1e (Helicopters: take off weight 3000 to 4500 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a closed circuit of 100 km without payload
Performance: 334.69 km/h
Date: 1982-02-06
Course/Location: Palm Beach, FL (USA)
Claimant David R. Wright (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1845 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1e (Helicopters: take off weight 3000 to 4500 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a closed circuit of 500 km without payload
Performance: 345.74 km/h
Date: 1982-02-08
Course/Location: Palm Beach, FL (USA)
Claimant Thomas F. Doyle Jr. (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

FAI Record File Num #1827 [Direct Link]
Status: ratified – current record
Region: World
Class: E (Rotorcraft)
Sub-Class: E-1e (Helicopters: take off weight 3000 to 4500 kg)
Category: General
Group: 2 : turbine
Type of record: Speed over a closed circuit of 1 000 km without payload
Performance: 305.10 km/h
Date: 1982-02-09
Course/Location: Palm Beach, FL (USA)
Claimant David R. Wright (USA)
Rotorcraft: Sikorsky S-76 A (N5445J)
Engines: 2 Allison 250-C30

Cutaway illustration of a Sikorsky S-76A. (Sikorsky Archives)
Cutaway illustration of a Sikorsky S-76A. (Sikorsky Archives)

The Sikorsky S-76A is a twin-engine intermediate class helicopter that can be configured to carry 6 to 12 passengers. It is used as an executive transport, a scheduled passenger airliner, utility transport, and search and rescue aircraft. The helicopter is certified for instrument flight and has retractable tricycle landing gear.

The prototype was rolled out at Stratford, Connecticut on 11 January 1977 and the first flight took place on 13 March. It was certified in 1978 and the first production aircraft was delivered to Air Logistics, 27 February 1979.

The number 2 Sikorsky S-76 makes the type’s first flight, 13 March 1977. (Sikorsky Historical Archives)

The S-76A is 52 feet, 6 inches (16.00 meters) long with rotors turning. The fuselage has a length of 43 feet, 4.43 inches (13.219 meters) and a width of 8 feet (2.44 meters).  The helicopter’s overall height is 14 feet, 5.8 inches (4.414 meters). The four bladed composite main rotor is 44 feet (13.41 meters) in diameter. The blades are attached to a one-piece forged aluminum hub and use elastomeric bearings. As is customary with American helicopters, the main rotor turns counter-clockwise as seen from above. (The advancing blade is on the right.) The four-bladed tail rotor has a diameter of 8 feet (2.438 meters) and turns clockwise as seen from the helicopter’s left. It is mounted in a pusher configuration on the left side of the tailboom. The tail rotor is constructed of composite airfoils mounted to graphite spars.

The S-76A was equipped with two Allison 250-C30 turboshaft engines rated at 557 shaft horsepower, each. Subsequent variants have been built with Turbomeca Arriel 1S and 2S engines, as well as Pratt and Whitney PT6B-3A and PW210S engines with up to 1,077 shaft horsepower, each.

The S-76 has an empty weight of 7,007 pounds (3,178 kilograms). The S-76A maximum gross weight was 10,500 pounds (4,763 kilograms). Beginning with the S-67B, this was increased to 11,700 pounds (5,307 kilograms).

The Sikorsky S-76 has a maximum cruise speed of 155 knots (287 kilometers per hour). It can hover in ground effect (HIGE) at 7,050 feet (2,149 meters) or out of ground effect (HOGE) at 3,300 feet (1,006 meters). The service ceiling is 13,800 feet (4,206 meters).

The helicopter was designed with offshore oil support as a major consideration. It was intended to carry 2 pilots and 12 passengers 400 nautical miles. Maximum range with no reserve is 411 nautical miles (762 kilometers).

Sikorsky built 307 S-76As. More than 1,000 of all variants have been built. The current production model is the S-76D.

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

© 2018, Bryan R. Swopes

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