Sikorsky Aircraft Corp. announced at the 2000 Farnborough Air Show that it is increasing the S-92 helicopter's cabin length by 16 in, reducing the height of its tail pylon, and relocating its horizontal stabilizer. This is being done in response to customer requests for additional cabin space and a larger main door. The extension of the forward part of the cabin will permit the installation of a 50-in-wide door to improve hoisting capabilities and accommodate a Stokes litter during search and rescue operations. The tail pylon was reduced by approximately 40 in to offset the additional weight from the cabin extension. The third through fifth S-92 prototype aircraft and all production aircraft will feature these changes.
Other benefits were realized with these design changes. These include an improved fold configuration for shipboard use and increased birdstrike protection by relocating the tail rotor driveshaft and controls aft of the tail spar. According to Sikorsky, these changes will also move the aircraft's center of gravity forward, resulting in a flatter hover attitude. This could improve visibility for confined and shipboard landings and increase aft fuselage clearance on landing.
The S-92, which evolved from the S-70 Black Hawk and Seahawk aircraft designs, is available in 19-passenger commercial or 22-troop utility configurations. According to the company, the S-92 will be the first helicopter that will be fully certified to the harmonized FAA and JAA Part 29 requirements.
S-92 development is being carried out by an international team of companies led by Sikorsky including Embraer of Brazil, Gamesa of Spain, Mitsubishi Heavy Industries of Japan, Jingdezhen Helicopter Group/CATIC of the People's Republic of China, and Aerospace Industrial Development Corp. of Taiwan. Major subcontractors include General Electric, Rockwell Collins, and Hamilton Sundstrand.
Demonstration flights for the program have confirmed the aircraft's hover and forward flight capabilities. Sikorsky has also demonstrated tethered hover at the equivalent of 32,000 lb and very long-range missions with an overload takeoff weight of 30,000 lb. The company has also reported that payload/range performance continues to meet the requirement of 19 passengers for 400 nmi with a fuel reserve.
Frank Bokulich
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Aerospace Engineering September 2000
