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57-596: The Sikorsky S-76 is a medium-size commercial utility helicopter designed and produced by the American helicopter manufacturer Sikorsky Aircraft . It is the company's first helicopter specifically developed for the civilian market. The S-76 was developed during the mid-1970s, originally being designated S-74 but renamed in honor of the U.S. Bicentennial . Drawing upon its recently-developed S-70 helicopter, it features twin turboshaft engines, four-bladed main and tail rotors, and retractable landing gear . On 13 March 1977,

114-436: A general aviation aircraft and hundreds of millions of dollars for a commercial aircraft ; certification delays can cost millions of dollars and can decide a program's profitability. A type certificate (TC) is issued to signify the airworthiness of the approved design or "type" of an aircraft to be manufactured. The TC is issued by a regulatory authority, and once issued, the design cannot be changed unless at least part of

171-540: A tablet computer , the take off and landing phases were also performed autonomously. During the 2010s, many S-76 operators elected to replace the type with newer medium-lift rotorcraft, such as the AgustaWestland AW139 . In early 2020, it was observed that, while the S-76D was no longer compliant with FAA regulations to permit its sale to US-based customers, sales were still possible to several other countries. The S-76

228-455: A crucial role in military operations by providing defensive capabilities in scenarios of evacuation and cargo transportation, as well as offensive roles in fire support and surveillance. Their ability to adapt to different mission requirements contribute significantly to the success of military objectives . Type certificate For up to three seats, primary category aircraft certification costs around US$ 1 million, US$ 25 million for

285-563: A drooped leading edge . The rotor tips are tapered and swept back. The rotor blades on later-build S-76s feature ice protection measures. The flight controls are servo -assisted and have a Stability Augmentation System fitted. A retractable nosewheel undercarriage is fitted, the reduced drag from this arrangement is credited with increasing the S-76A's cruising speed by 6 knots (6.9 mph; 11 km/h). Emergency flotation gear can be fitted, which uses helium -filled bags to increase buoyancy in

342-451: A given TC, each one need not be tested as rigorously but the confidence demonstrated by the TC is conferred, when the aircraft has been assigned a certificate of airworthiness (CoA). A CoA is issued for each aircraft that is properly registered if it conforms to its type design and ready for safe operation. The CoA is valid and the aircraft may be operated as long as it is maintained in accordance with

399-410: A more conventional design. The main rotor is furnished with a single piece aluminum hub fitted with elastomeric bearings, which are designed not to require lubrication or any other kind of maintenance throughout its design life. The main rotor blades have titanium spars and incorporate a ten degree twist to provide an even loading when hovering, while they use a non-symmetrical airfoil section with

456-516: A new variant may require re-certification. Again the basic process of type certifications is repeated (including maintenance programs). However, unaltered items from the basic design need not be retested. Normally, one or two of the original prototype fleet are remanufactured to the new proposed design. As long as the new design does not deviate too much from the original, static airframes do not need to be built. The resultant new prototypes are again subjected to flight tests. Upon successful completion of

513-401: A proposed timetable of actions required for certification tests. With the application, the regulations to be applied will usually be frozen for this application for a given amount of time in order to avoid a situation where the applicant would have to change the design as a result of changed regulation. An initial design sample known as a prototype is built. This refers to either the aircraft,

570-799: Is a multi-purpose helicopter capable of pursuing a wide array of tasks. They have proven useful in both civilian and military operations, with versatility being their defining trait. Helicopters play a crucial role in various aspects of civilian safety. Police and fire rescue aircraft demonstrate exceptional versatility across a broad spectrum of task. Common applications for civilian utility include traffic surveillance, medical evacuations , news coverage, and search and rescue missions. Recently, usage has been extended to air evacuations , air and water pollution control, emergency cargo transportation (including blood, organs, and special equipment), and as helitankers in aerial firefighting . Traditionally, helicopters with three placed reciprocating engines , such as

627-470: Is drawn with inputs from tests results and also from initial customers' engineering departments. The proposed maintenance program is submitted to the regulators for comment and approval. After successful completion of ground and flight tests, along with an approved maintenance program, the prototype is approved, and the firm is granted the TC for the prototype (as understood that it should include all furnished equipment for its intended role). The legal term for

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684-498: Is in civil service around the world with airlines, corporations, hospitals, and government operators. The world's largest civilian fleet is the 79 Sikorsky S-76 helicopters operated by CHC Helicopter Corporation . [REDACTED]   Canada Data from Sikorsky General characteristics Performance Avionics Related development Aircraft of comparable role, configuration, and era Related lists Utility helicopter A utility helicopter

741-405: Is tested, the flight tests may cover the whole world. Tests may also cover different environments - high and low altitude, freezing and hot climates, and so on, to confirm correct performance throughout the aircraft's design envelope . In parallel with aircraft testing, the applicant firm also draws up maintenance program to support continuous airworthiness after approval of the design. The program

798-422: Is thus compromised. The regulators will now issue an airworthiness directive to the type certificate holder and to all owners globally. The directives normally consists of additional maintenance or design actions that are necessary to restore the type's airworthiness. Compliance is mandatory and thus if an operator does not comply with an AD, then the datum aircraft is not considered airworthy and further operation of

855-580: The 47G Series and the Hughes 300C were the primary choices for civilian use. However, the preference has been shifted towards turbine engines . The FH-100 and the Bell 206A JetRanger are examples of turbine engine helicopters which have proven to be more effective in operational scenarios. The arising issue with civilian use helicopters is the price tag of the turbine engine helicopters. With initial cost being around $ 100,000, difficulties are posed when budgeting for

912-561: The British Isles . According to Jason Lambert, Sikorsky's vice president of commercial and military systems, the S-76 had proven itself to be particularly popular amongst VIP customers. By 2020, according to Sikorsky, ten countries operated S-76s to carry their heads of state . S-76s have been periodically used to test new technologies and capabilities. The highly-modified S-76 SHADOW (Sikorsky Helicopter Advance Demonstrator of Operators Workload)

969-498: The Civil Aviation Administration of China (CAAC). When changes are needed to an airframe or on-board equipment, there are two options. One is to initiate a modification by the type design holder (manufacturer), and the other is to request a third party Supplemental type certificate (STC). The choice is determined by considering whether or not the change constitutes a new design (i.e. introduces risk not considered in

1026-493: The September 11 attacks . The certifying authority issues an AD when an unsafe condition is found to exist in a product (aircraft, aircraft engine, propeller, or appliance) of a particular type design. ADs are used by the certifying authority to notify aircraft owners and operators of unsafe conditions and to require their correction. ADs prescribe the conditions and limitations, including inspection, repair, or alteration under which

1083-580: The U.S. Bicentennial . The company had set the design goal of producing a medium helicopter suitable for corporate transportation and the oil drilling industry. Sikorsky's design work on the S-70 helicopter (which was selected for use by the United States Army as the UH-60 Black Hawk ) was utilized in the development of the S-76, incorporating S-70 design technology in its rotor blades and rotor heads. It

1140-540: The 2010s; only a dozen S-76s were delivered between 2016 and 2020. During September 2013, it was announced that the Chinese manufacturer Changhe Aircraft Industries Corporation had been contracted to produce the S-76D airframe. By 2022 April, in excess of 875 S-76s had reportedly been built. During March 2022, Sikorsky announced that it had halted new orders for the S-76 while potential overseas manufacturing partners and licensing opportunities were being evaluated. Reasons for

1197-761: The A340-600 which is based on the Airbus A340-200 and the A340-300. Any additions, omissions or alterations to the aircraft's certified layout, built-in equipment, airframe and engines, initiated by any party other than the type certificate holder, need an approved supplementary ("supplemental" in FAA terminology) type certificate, or STC. The scope of an STC can be extremely narrow or broad. It could include minor modifications to passenger cabin items or installed instruments. More substantial modifications may involve engine replacement, as in

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1254-659: The Blackhawk modifications to Cessna Conquest and Beechcraft King Air turboprops , or a complete role change for the aircraft, such as converting a B-17 or Stearman into an agricultural aircraft. STCs are applied due to either the type certificate holder's refusal (frequently due to economics) or its inability to meet some owners' requirements. STCs are frequently raised for out-of-production aircraft types conversions to fit new roles. Before STCs are issued, procedures similar to type certificate changes for new variants are followed, likely including thorough flight tests. STCs belong to

1311-403: The S-76 at its Connecticut facility. The S-76 is of a conventional configuration, with a four-bladed fully articulated main rotor and a four-bladed anti-torque rotor on the port side of the tailboom. It is powered by a pair of turboshaft engines, which are located above the passenger cabin. On the prototypes and initial production aircraft, these engines were Allison 250-C30s , a variant of

1368-464: The S-76 waned during the 2010s, newer helicopters such as the AgustaWestland AW139 proved to be stiff competition. During March 2022, Sikorsky halted new orders for the S-76, but stated that it was looking at opportunities for future overseas manufacturing with foreign partners. The development of the S-76 commenced during the mid-1970s as the S-74 . The S-74 was subsequently redesignated the S-76 in honor of

1425-496: The STC holder and are generally more restrictive than type certificate changes. The TC holder remains responsible for the continued integrity of the approved aircraft type design and must continue to be the focal point for resolving issues that may require corrective action. This requires the continued capability, or access to a capability, of providing appropriate technical solutions for service difficulties or mandatory corrective action. If

1482-399: The U.S. these sub-assemblies must meet requirements in the applicable Technical Standards Order (TSO). To meet those requirements the design documents are examined for compliance with the applicable Minimum Operating Performance Standards (MOPS) applicable to that sub-assembly. MOPS are published by expert industry groups such as: RTCA Inc., EUROCAE, and SAE. When aircraft are produced to meet

1539-464: The affected aircraft type would be unlawful , making the operator liable to legal action by the relevant national aviation authority, and rendering null-and-void any of the operator's insurance policies relating to the type, such as hull loss and accident third party coverage. ADs may also be raised with changes of the local or global aviation rules and requirements, e.g., the requirement to fit armored cockpit doors for all passenger airliners after

1596-411: The airworthiness certificate of their aircraft to remain valid. Other continuing airworthiness activities include additional tasks associated with the maintenance program and design changes to be accomplished via: Sometimes during service, the aircraft may encounter problems that may compromise the aircraft's safety, which are not anticipated or detected in prototype testing stages. The aircraft design

1653-472: The applicable airworthiness requirements and remains in a condition for safe operation throughout its operating life called continuing airworthiness . A maintenance program is issued by the aircraft operator and approved by the regulatory authority of the state of registry to maintain the airworthiness of the aircraft of the type owned by the operator. Maintenance tasks outlined in the maintenance program have to be scheduled and timely accomplished in order for

1710-407: The applicant design organisation submits documents to their local aviation regulating body, detailing how the proposed aircraft type design would fulfill the airworthiness requirements. After investigations by the regulator, the final approval of such documents (after the required comments and amendments in order to fulfill the laws), becomes the basis of the certification. The firm follows it and draws

1767-509: The bulletins and report the decision to the regulatory authority of the state of the aircraft registry. Sometimes SBs can become mandated by relevant ADs. Often the basic design is enhanced further by the type certificate holder. Major changes beyond the authority of the service bulletins require amendments to the type certificate. For example, increasing (or decreasing) an aircraft's flight performance, range and load carrying capacity by altering its systems, fuselage, wings or engines resulting in

Sikorsky S-76 - Misplaced Pages Continue

1824-411: The cabin, which can accommodate a further 12 passengers in three rows of four, or between four and eight passengers in a more luxurious executive seating configuration. Later models can be flown by a single pilot when provisioned with an appropriately configured cockpit. The S-76 was not originally designed with crashworthy fuel systems, leading to difficulties continuing production after an FAA requirement

1881-515: The certification program, the original type certificate is amended to include the new variant (normally denoted by a new model number additional to the original type designation). Typical examples are; the Boeing 737NG (737-600, 737-700, 737-800 and 737-900) which replaced the 737 Original family (737-100 and 737-200) and the 737 Classic family (737-300, 737-400 and 737-500) and the Airbus A340-500 and

1938-553: The certification program, with one aircraft used to certify the optional rotor electric ice-protection system. The "D" model is powered by 1,050 hp (783 kW) Pratt & Whitney Canada PW210S engines driving composite rotors and incorporates active vibration control. Performance is substantially improved with the added power, but initial certification retains the same 11,700 lb (5,307 kg) gross weight and maximum 155 kn (287 km/h) cruise speed as earlier models. The rate of manufacturing noticeably declined during

1995-635: The early 2000s, the S-76C+ was the main version in production; it was equipped with twin Turbomeca Arriel 2S1 engines with FADEC and a Honeywell EFIS suite. This version also incorporated active noise suppression, vibration dampers and a composite main rotor. On 3 January 2006, the S-76 C++ replaced earlier versions in production; it is powered by twin Turbomeca Arriel 2S2 engines and incorporates an improved and quieter transmission as well as minor changes in

2052-553: The engines or the propeller, depending on the basis of the certification. For the purpose of illustration, the discussion shall be limited to the aircraft. Normally a few prototypes are built, each subject to different tests. The prototypes are first used for ground and system tests. One of the prototypes (known as the "static airframe") is subject to destructive testing, i.e., the prototype is subject to stress beyond normal and abnormal operations until destruction. The test-results are compared with initial submitted calculations to establish

2109-401: The event of a forced landing on water. The fuselage of the S-76 is made from both metal and composite materials ; while the nose is composed of fiberglass , the cabin area primarily employs a light alloy honeycomb structure , the semi- monocoque tailboom is also constructed of light alloy. A pair of pilots are typically seated in a side-by-side arrangement in the cockpit, situated ahead of

2166-519: The firm is now the "type certificate holder". Subsequently, the prototype now serves as a template for serial aircraft production and the aircraft rolling out of the factory should be identical to the prototype within the frames outlined in a TC data sheet, and each given a serial number (a "series aircraft"). As the aircraft enters into service, it is subject to operational wear and tear which may cause performance degradations. The set of processes by which an aircraft, engine, propeller or part complies with

2223-434: The first type design). If so, then type design holder must develop and approve a modification to the type design. If the regulatory authority agrees the change does not introduce new risk, the STC option is available. An STC is less expensive because the design change can be developed by a specialized design organization, a generally more flexible and efficient process than going through the original manufacturer. The STC defines

2280-469: The hold included decreasing sales volume, the high cost of supply and manufacturing, and the prohibitive costs associated with adapting the S-76 to meet increasing safety mandates. This move effectively ended production of the S-76 following the completion of the three orders that were outstanding, and represented a withdrawal by Sikorsky from the medium commercial helicopter market. Sikorsky has stated that it will continue to actively manufacture spare parts for

2337-452: The holder is no longer capable or if the TC is transferred to another holder a regulatory authority should take appropriate action in accordance with the national legislation. In the case of the TC being transferred to another holder the new holder shall be capable of fulfilling the TC holder responsibilities in following ADs and providing technical support to keep the type design current with the applicable airworthiness requirements, even after

Sikorsky S-76 - Misplaced Pages Continue

2394-499: The interior equipment and avionics. By January 2006, Sikorsky had secured 92 orders for this model. Development of the follow-on S-76D was subject to four years of delays due to technical problems in expanding the flight envelope. On 7 February 2009, the prototype conducted its first flight, and type certification was initially expected during 2011 while deliveries were forecast to start at the end of that year. The FAA issued certification on 12 October 2012. Three prototypes were used in

2451-576: The necessary modifications. Such modifications include night vision capabilities , infrared , and radar . In military terms, a utility helicopter is an aircraft designed to transport troops, but is versatile in performing various combat roles. These tasks include command and control , logistics, casualty evacuation, and fire support . The defining characteristics of these helicopters are lightweight frames capable of quick maneuvers , and space, for transporting troops and cargo. Common types of cargo include ammunition, weapons, and food. These aircraft play

2508-488: The off-shore oil drilling industry; later on, demand shifted towards the VIP sector of the market. It performed several noteworthy flights, such as the first circumnavigation of the world in an east-to-west direction by a helicopter, and an autonomous demonstration flight during 2016. Sikorsky also used individual helicopters, often heavily modified for the purpose, for experimental purposes and to support other programmes. Demand for

2565-592: The popular Allison 250 engine that was developed specially for the S-76l it had a single-stage centrifugal compressor instead of the multi-stage axial /centrifugal compressor of earlier models of the engine, rated at 650 shp (480 kW) for takeoff. These engines are connected to the main rotor by the main gearbox, a three-stage unit with a bull gear as its final stage, rather than the planetary gear that had been used by previous generations of Sikorsky helicopters. This arrangement has 30% fewer parts and lower costs than

2622-587: The process for certification is repeated to cover the changes. The TC reflects a determination made by a regulatory authority that the type design is in compliance with airworthiness requirements. Examples of regulatory authorities are the United Kingdom's Civil Aviation Authority (CAA), the U.S. Federal Aviation Administration (FAA), the European Aviation Safety Agency (EASA), Transport Canada , Brazil’s Agência Nacional de Aviação Civil and

2679-456: The product design change, states how the modification affects the existing type design, and lists serial numbers of the aircraft affected. It also identifies the certification basis for regulatory compliance for the design change. The TC implies that aircraft manufactured according to the approved design can be issued an airworthiness certificate . To meet those requirements the aircraft and each sub-assembly must also be approved. For example, in

2736-477: The product may continue to be operated. With increasing in-service experience, the type certificate holder may find ways to improve the original design resulting in either lower maintenance costs or increased performance. These improvements (normally involving some alterations) are suggested through service bulletins to an aircraft owners/operators as optional (and may be extra cost) items. The owner/operator shall exercise their discretion whether or not to incorporate

2793-423: The production of the aircraft type has stopped but many out-of-production aircraft continue useful lives. STCs are also bound by the same rules. When the holder decides to stop supporting the aircraft type without the transfer of TC holder responsibilities, the TC is returned to the issuing regulatory authority and the remaining aircraft fleet can be grounded by the current states of registry until further decisions on

2850-600: The prototype performed its maiden flight . The initial production variant was the S-76A, the first deliveries of which took place on 27 February 1979. Several improved models were produced over time, including the S-76 Mk II launched in 1982, and the S-76B in 1987. Development of the S-76D was particularly troubled, being delayed by four years of delays due to flight envelope issues; it was finally certified for operation on 12 October 2012. The S-76 initially encountered strong demand from

2907-689: The rules issued by the regulatory authority. The concept of a 'type certificate' was introduced by the "Air Navigation Regulations" published in May 1919 by the UK's Secretary of State for Air , Winston Churchill . The Buhl-Verville CA-3 Airster was the first aircraft to receive a type certificate in the US, (i.e. A.T.C. No. 1) issued by the Aeronautics Branch of the Department of Commerce on March 29, 1927. Initially,

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2964-416: The ultimate structural strength. Other prototypes will undergo other systems tests until the satisfaction of the regulators. With all ground tests completed, prototypes are made ready for flight tests. The flight tests are flown by specially approved flight test pilots who will fly the prototypes to establish the ultimate flight limits which should be within the airworthiness rules. If a long range airliner

3021-631: The world in an east-to-west direction, piloted by the Australian adventurer Dick Smith . Several airlines have operated the S-76A on scheduled services, including Helijet Airways of Vancouver, British Columbia , Canada. During the campaigning in the run up to the 2005 United Kingdom general election , both the Labour and the Conservative parties dispensed with conventional 'battle buses' in favour of S-76 helicopters to quickly transport their leaders around

3078-585: Was built to demonstrate its advanced cockpit for single-pilot operations and to study the human engineering interface between the pilot and the cockpit controls and displays; this was in aid of the RAH-66 Comanche armed reconnaissance helicopter programme. During the 2010s, an S-76 was configured for autonomous operation and demonstrated this ability in June 2016, flying for a distance of around 30 miles (48 km) with no human intervention beyond limited inputs made via

3135-446: Was implemented in April 2020. Early on in its commercial career, the S-76 became popular for offshore operations, such as to oil rigs . Numerous operators have either purchased or leased the type specifically to operate in this sector. During 1982, the S-76A set multiple class records for range, climb, speed and ceiling. In June 1995, the S-76 became the first helicopter to circumnavigate

3192-457: Was the S-76A. Several improved models were produced over time. During 1982, the S-76 Mk II, equipped with more powerful engines and other refinements, was introduced. In 1987, production of the S-76B, powered by Pratt & Whitney Canada PT6B-36A and Pratt & Whitney Canada PT6B-36B engines; it was capable to attaining a maximum speed of 155 kn (287 km/h) at sea level. By early 2001, in excess of 500 S-76s had been delivered. During

3249-549: Was the first Sikorsky helicopter designed purely for commercial rather than military use. On 13 March 1977, the prototype performed its maiden flight . On 21 November 1978, initial US Federal Aviation Administration type certification was granted, while the first customer delivery took place on 27 February 1979. During late 1978, the S-76 was officially named "Spirit", however, this name was officially dropped by Sikorsky on 9 October 1980, reportedly due to translation issues into some foreign languages. The first production variant

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