Sikorsky S-92

The Sikorsky S-92 is a four-bladed twin-engine medium-lift helicopter built by Sikorsky Aircraft for the civil and military helicopter market. The S-92 was developed from the Sikorsky S-70 helicopter and has similar parts such as flight control and rotor systems.

The H-92 Superhawk is a military version of the S-92 in the utility transport role, capable of carrying 22 troops. The H-92 can also be configured for specific missions, including Search and Rescue and executive transportation. The CH-148 Cyclone is a shipboard maritime helicopter variant currently under development for the Canadian Forces. From February 2009, the S-92 program was placed under Sikorsky Global Helicopters, Sikorsky's new civil helicopter business unit.

Development
Sikorsky Aircraft first displayed a S-92 mockup of the planned helicopter in 1992. The S-92 was to be offered for sale beginning in 1993, but due to a decline in the international market for helicopters, this was delayed. In 1995 Sikorsky formed Team S-92 with international partners and launched the helicopter program at the Paris Airshow that year. Sikorsky developed the S-92 to compete with civil aircraft such as the Aerospatiale/Eurocopter Super Puma. The helicopter uses a new airframe with dynamic components based on the S-70/H-60 components. The S-92 took its maiden flight on December 23, 1998 at the Sikorsky Development Flight Center, West Palm Beach, Florida.

In July 2000, Sikorsky announced design changes to the S-92. The fuselage of prototype #3 was lengthened by 16 in (40 cm) aft of the cockpit, the tail pylon was shortened by 41 in (1.04 m), and the horizontal stabilizer was repositioned from the left side opposite the tail rotor to the right side at the base of the tail pylon. The modifications to the tail solved a pitch stability issue discovered during flight testing, and were reported to allow the aircraft to meet a key requirement of the Nordic Standard Helicopter Program (NSHP) for shipboard stowage. The lengthening of the fuselage and shortening of the tail pylon shifted the aircraft center of gravity (CG) forward, permitting a more level attitude in flight. The longer fuselage allowed for an additional row of three seats, as well as a larger passenger door option for Search and Rescue (SAR) customers. Sikorsky incorporated the changes into the following two prototypes as the production standard configuration. Some reports suggested that the modifications were actually to resolve damage from structural design flaws.

The S-92 is built and customized in Sikorsky's Coatesville, Pennsylvania facility. The S-92 received Federal Aviation Administration (FAA) part 29 type certification on December 19, 2002, and received International European Aviation Safety Agency/Joint Aviation Authorities (EASA/JAA) certification on June 8, 2004. In June 2009, Sikorsky Aircraft entered into a joint-venture with Tata Advanced Systems Limited (TASL) for S-92 manufacturing in India for export and domestic markets. A US$ 200 million manufacturing plant will be operational in Hyderabad by 2010. Initially, TASL will supply the complete cabins for the S-92 to Sikorsky. The first cabin was delivered in November 2010.

Design


The S-92 is multi-purpose helicopter powered by twin GE CT7-8A turboshaft engines and has an aluminum airframe and some composite components. The four-bladed fully articulated composite main rotor blade is wider and has a longer radius than the Sikorsky S-70. The tapered blade tip sweeps back and angles downward to reduce noise and increase lift. Most of the rotor system components aside from the blades are titanium. Tethered hover flight has recorded 31,000 lb of lift generated, both in and out of ground effect.

The S-92 also features an active vibration control system with vibration sensors and structurally mounted force generators. The system provides for comfortable flight and acoustic levels below certification requirements. This system also prolongs airframe life by reducing fatigue loads on the aircraft.

A number of safety features such as flaw tolerance, bird strike capability, and engine burst containment have been incorporated into the design. Adherence to FAA FAR part 29 has led the FAA certification board to call the S-92 the "safest helicopter in the world". The S-92 reportedly met the FAR part 29 "run dry" requirement by asserting the loss of oil pressure in the main gear box is "extremely remote".

In February 2011, Norwegian newspaper Dagbladet reported health concerns from the noise and vibrations in the aircraft. Pilots are alleged to get tinnitus, heart problems and other.

Operational history
The S-92 received FAA certification in 2002, and International certification in June 2004. The first S-92 was delivered to launch customer PHI Inc in September 2004.

Competitions
Sikorsky entered the VH-92 variant of the S-92 into the VXX competition for U.S. Presidential helicopter Marine One, but lost to the VH-71 Kestrel. However, the competition was restarted in 2010 due to ballooning VH-71 development costs, allowing Sikorsky to return to the melee with the VH-92 in April 2010. By mid-2013, all other aircraft makers are understood to have dropped out of the contest, leaving only Sikorsky.

Sikorsky entered a Search and rescue variant of the H-92 in US Air Force's CSAR-X combat search and rescue competition beginning in 2006. Its competitors were the AgustaWestland EH101 and HH-47, but by December 2012 all other manufacturers had withdrawn. Richard Aboulafia of the Teal Group expects the company to offer a S-92 version. Flight International magazine expects Sikorsky to bid a version of its MH-60 special operations helicopter.

The S-92 was a candidate for the Norwegian All Weather Search and Rescue Helicopter (NAWSARH) that is planned to replace the Royal Norwegian Air Force Westland Sea King Mk.43B in 2015. The other candidates for the NAWSARH contract of 10–12 helicopters were AgustaWestland AW101, Bell Boeing V-22 Osprey, Eurocopter EC225, and NHIndustries NH90. The V-22 was eliminated from the competition in 2012. The S-92 was removed from the competition in July 2013 with AgustaWestland and Eurocopter remaining.

The S-92 competed with the Eurocopter EC225 for the UK Search and Rescue - Helicopter (SAR-H) program. In February 2010, the S-92 was selected by the UK to replace 40 search and rescue helicopters with 25 to 30 S-92s, though it has subsequently been announced that Soteria, the preferred supplier, will not be used. The Irish Coast Guard is replacing its Sikorsky S-61 fleet with the S-92. First aircraft was delivered on 29 January 2012. The aircraft are operated by CHC Helicopter.

S-92A
The S-92A is the civilian variant and is available in a number of versions. The civil transport version has an airliner-type interior which seats 19 passengers. The utility transport version has 22 side-facing seats with a full cabin width rear ramp. The 733 ft³ interior cabin area can also be configured to accommodate up to three airline-style LD3 cargo containers. Additional stowage space is available in the 140 ft³ area located in the aft ramp compartment. During development it was referred to as the S-92C Helibus.

H-92 Superhawk
The H-92 Superhawk is the military variant of the S-92. It has been demonstrated to the U.S. Air Force, Marine Corps and Coast Guard. The H-92 has more powerful GE CT7-8C engines, rated at 3,070shp (2,300 kW) and, unlike the S-92, has fly-by-wire flight controls. The search and rescue variant provides space for seats, litters, auxiliary fuel and SAR emergency equipment.

In July 2004, the H-92 Superhawk was selected by Canada for its Maritime Helicopter Programme (MHP) as the CH-148 Cyclone. Canada ordered 28 helicopters in November 2004. The program has been delayed multiple times.

Government operators

 * 🇦🇿 Azerbaijan
 * Government of Azerbaijan
 * Royal Air Wing
 * See Sikorsky CH-148 Cyclone
 * Irish Coast Guard
 * Kuwait Air Force
 * Ministry of Interior
 * Government of South Korea
 * South Korea Coast Guard (on order)
 * Government of Thailand - 3
 * Government of Turkey
 * Government of Turkmenistan - 2
 * Her Majesty's Coastguard - 4
 * Government of South Korea
 * South Korea Coast Guard (on order)
 * Government of Thailand - 3
 * Government of Turkey
 * Government of Turkmenistan - 2
 * Her Majesty's Coastguard - 4
 * Government of Turkmenistan - 2
 * Her Majesty's Coastguard - 4
 * Her Majesty's Coastguard - 4
 * Her Majesty's Coastguard - 4

Civil operators

 * Brunei Shell Petroleum
 * Líder Aviação
 * CHC Helicopter
 * Cougar Helicopters
 * Eastern General Aviation
 * China Southern Airlines
 * Bristow Norway
 * Eastern General Aviation
 * China Southern Airlines
 * Bristow Norway
 * Bristow Norway
 * Bristow Norway

Accidents and notable incidents
On July 2, 2008, a S-92A (registration VH-LOH, serial number 920036) operated by Canadian Helicopters Corporation (CHC) Australia was returning from an offshore oil facility en route to Broome, Australia with 2 pilots and 14 passengers on board when it suffered a "massive loss of main gearbox oil". The crew made an emergency descent and landing following the activation of onboard warning systems.

On July 19, 2008, an S-92 carrying Rev. Sun Myung Moon crashed in South Korea. The helicopter was flying in inclement weather which forced it down on a hillside. The 16 people aboard were slightly injured in the crash.

On March 12, 2009, Cougar Helicopters Flight 91, an S-92A operated by Cougar Helicopters carrying 18 passengers and crew en route to oil platforms off the coast of Newfoundland, crashed and sank in 170 m of water during an attempted ditching. One person was rescued from the North Atlantic with serious injuries and the others did not survive. The crash was determined to be caused by total gearbox oil loss due to fracture of the main gearbox oil filter studs.