"The Sikorsky S-76, a medium-class hauler, has proven a relative commercial success for Sikorsky Aircraft with over 1,000 units produced for various markets."
The Model S-76 was developed by Sikorsky Aircraft for the ultra-competitive medium-lift commercial helicopter market. Its design was influenced by the company's work to bring the S-70 about (this becoming the famous UH-60 'Black Hawk' in military service). The product began as the "S-74" during the middle part of the 1970s and intended for the oil industry and VIP / corporate transport sectors. In line with the American celebrations of 1976 ( the country's bicentennial), the model was redesignated to "S-76". The end-product became a popular entry into the medium-lift category with nearly 1,100 examples produced.
The S-76 was given a twin-turboshaft engine arrangement and these systems were fitted over the passenger cabin in the usual way. The cockpit seated its crew of two side-by-side aft of a short nose assembly with generally good vision out-of-the-cockpit. Access was by way of hinged, Automobile-style doors while the passenger section carried rectangular sliding doors to either side of the fuselage. The tail stem was well-contoured with the existing lines of the fuselage and housed a drive shaft powering a four-bladed tail rotor offset to portside. This was used to balanced the torque effect caused by the four-bladed main rotor system mounted atop the passenger cabin. A wheeled tricycle undercarriage was installed to allow for ground running and made wholly retractable to maintain aerodynamic efficiency during flight.
The original production became the S-76A and this model was given 2 x Rolls-Royce (Allison) 250-C30 turboshaft engines of 650 horsepower each. Some 284 units followed in production. The utility-minded form became the S-76A "Utility" and this mark featured a reinforced cabin floor.
The S-76A+ was the S-76 outfitted with French Turbomeca Arriel 1S turboshaft engines and seventeen were modified in this fashion. Similarly, the S-76A++ carried 2 x Turbomeca Arriel 1S1 turboshaft engines. The S-76A Mk II was an improved all-weather hauler with refinements as well as uprated turboshaft engines.
The S-76B was produced with 2 x Pratt & Whitney Canada PT6B-36A or PT6B-36B engines and 101 were made to this standard. The S-76C was given 2 x Turbomeca Arriel 1S1 engines and 43 were followed in production. The S-76C+ was similar but carried 2 x Turbomeca Arriel 2S1 engines (with complete digital FADEC support) and 35 followed. The S-76C++ was next and this product sported Turbomeca Arriel 2S2 engines instead. The S-76D was completed with 2 x Pratt & Whitney Canada PW210S engines and a Thales "Topdeck" avionics fit.
The S-76C++ variant was crewed by two with seating for thirteen. It was given an overall length of 52.5 feet with a height of 14.5 feet. Empty weight was listed at 7,000lb with a gross weight of 11,700lb. Power from the 2 x Turbomeca Arriel units became 922 horsepower each allowing for a maximum speed of 180 miles-per-hour with a range out to 475 miles and a service ceiling of about 13,800 feet.
Military variants of the S-76 model were the "AUH-76" (based on the aforementioned S-76 Mk II model) and the H-76 "Eagle" which was proposed for maritime use - though not adopted by any one party. The S-76 "Shadow" was used in the development of the (ultimately abandoned) U.S. Army's RAH-66 "Comanche" light attack stealth helicopter program (detailed elsewhere on this site). A single S-76B was also modified with a fantail (shrouded) rotor unit for the same program and showcased at the 1991 Paris Air Show.
Operators of the S-76 ultimately ranged from Argentina and China to Turkmenistan and the United Kingdom in both military and civilian roles (as well as some Coast Guard services). Many of these original operators continue to operate the Sikorsky helicopter. CHC Helicopter Corporation of Canada services the offshore oil and gas industries with a fleet numbering nearly 80 S-76 platforms. Bristow Helicopters of Scotland is another well-known operator of the type.
November 2018 - United States Army aviation personnel have test-flown an autonomous development of the S-76B helicopter family (known specifically as the Sikorsky Autonomy Research Aircraft - or "SARA"). The model in question has been modified by Sikorsky (Lockheed) in conjunction with DARPA.
Power & Performance Those special qualities that separate one aircraft design from another. Performance specifications presented assume optimal operating conditions for the Sikorsky S-76 Medium-Lift Multirole Helicopter.
2 x Turbomeca Arriel 2S2 turboshaft engines developing 922 horsepower each and driving a four-bladed main rotor and four-bladed tail rotor. Propulsion
180 mph 290 kph | 157 kts Max Speed
13,780 ft 4,200 m | 3 miles Service Ceiling
472 miles 760 km | 410 nm Operational Range
City-to-City Ranges Operational range when compared to distances between major cities (in KM).
NYC
LON
LON
PAR
PAR
BER
BER
MOS
MOS
TOK
TOK
SYD
SYD
LAX
LAX
NYC
Structure The nose-to-tail, wingtip-to-wingtip physical qualities of the Sikorsky S-76 Medium-Lift Multirole Helicopter.
2 (MANNED) Crew
52.5 ft 16.00 m O/A Length
14.5 ft (4.42 m) O/A Height
7,011 lb (3,180 kg) Empty Weight
11,707 lb (5,310 kg) MTOW
Design Balance The three qualities reflected below are altitude, speed, and range. The more full the box, the more balanced the design.
RANGE
ALT
SPEED
Armament Available supported armament and special-mission equipment featured in the design of the Sikorsky S-76 Medium-Lift Multirole Helicopter .
Typically none though militarized "gunship" types fit light-class armament as necessary.
Variants Notable series variants as part of the Sikorsky S-76 family line.
S-76 - Base Model Designation
S-76A - Initial production model; fitted with Rolls-Royce 250-C30 turboshaft engines.
S-76A "Utility" - Base transport model; reinforced cabin floor; side sliding door panels.
S-76A+ - S-76 models re-engined with Turbomeca Arriel 1S engines.
S-76A++ - S-76 models re-engined with Turbomeca Arriel 1S1 engines.
S-76A Mk II - All-weather transport model; uprated engines.
S-76B - Fitted with Pratt & Whitney Canada PT6B-36A or PWC PT6B-36B engines; 101 examples.
S-76C - Fitted with Turbomeca Arriel 1S1 engines; 43 examples.
S-76C+ - Fitted with Turbomeca Arriel 2S1 FADEC engines; 35 examples.
S-76C++ - Fitted with Turbomeca Arriel 2S2 engines
S-76D - Fitted with PWC PW210S engines and Thales avionics suite; reduced noise.
AUH-76 - Armed utility transport based on S-76 Mk II model.
H-76 "Eagle" - Proposed militarized maritime patrol variant based on the S-76B; not produced.
S-75 - Advanced composite airframe experimental platform.
S-76 "SHADOW" - Single-seat experimental platform.
Operators Global customers who have evaluated and/or operated the Sikorsky S-76. Nations are displayed by flag, each linked to their respective national aircraft listing.
Total Production: 1,090 Units Contractor(s): Sikorsky Aircraft (Lockheed) - USA
[ Argentina; China; Honduras; Hong Kong; Japan; Jordan; Philippines; Saudi Arabia; Serbia; Spain; Taiwan; Thailand; Trinidad and Tobago; Turkmenistan; United Kingdom; United States ]
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Image from Sikorsky marketing material.
Going Further... The Sikorsky S-76 Medium-Lift Multirole Helicopter appears in the following collections:
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