The Sikorsky S-92 is an American twin-engine medium-lift helicopter built by Sikorsky Aircraft for the civil and military helicopter markets. 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 developed for the Royal Canadian Air Force to support naval operations of the Royal Canadian Navy. The Sikorsky VH-92 is a variant under development to replace the United States Marine Corps' Marine One U.S. Presidential transport fleet.
Development
After the 1973 oil crisis, major oil and gas companies began exploration further offshore, thus creating a need for aircraft such as the S-92 with sufficient capability.
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 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.
The S-92 features an active vibration control system, using vibration sensors and structurally mounted force generators to increase flight comfort and lower acoustic levels to below certification requirements. A 2008 study by Norway's Flymedisinsk Institute found that the S-92's vibration levels were 42 percent above that of the Eurocopter EC225 Super Puma; Sikorsky disputed this finding, saying that the study hadn't used their latest anti-vibration technology. In February 2011, as published on a Norwegian newspaper's website, the noise and vibration levels were reportedly subject to health concerns, allegedly causing tinnitus and heart problems.