Sikorsky Redesigns, Delays S-92

Sikorsky has redesigned key elements of its new S-92 utility helicopter, changes that are likely to delay FAA certification of the 19-seat aircraft by several months.
The aircraft's fuselage will be stretched 16 inches to accommodate a larger door, the horizontal stabilizer will be relocated to improve stability, and the tail pylon will be shortened by 40 inches to offset additional weight.

Tommy Thomason, Sikorsky's civil programs chief, said the combination of changes will allow the S-92 to maintain its "current" payload and range, will not have any impact on price, and will be incorporated on all production aircraft.

"The redesign began with a request from search and rescue operators, who felt a larger, 50-inch wide door was needed to improve hoisting capabilities and provide adequate room for a Stokes litter," Thomason said.

The changes move the aircraft's center of gravity forward, allowing a flatter hover attitude that improves visibility for confined and shipboard landings, while increasing aft fuselage ground clearance on landing.

The changes also improve the aircraft's shipboard "fold configuration," Sikorsky says, while relocating its tail rotor driveshaft and controls aft of the tail spar as part of the tail modification serves to improve bird-strike protection.

The prototype S-92 first flew in December 1998, and three aircraft including a ground test article are now involved in the test program. Aircraft 4 will be built this year, incorporating Rockwell Collins avionics, and Aircraft 5-formerly used on static displays-is slated to join the test series.

The S-92 is a contender for in the Nordic Standard Helicopter Program a multi-nation (Sweden, Finland, Norway, Denmark) bid for around 20 aircraft. Competitors to the S-92 include the EH101, NH90, Super Puma and Mi-17.

At Farnborough 2000, Sikorsky will feature utility-configured S-92 in the static display, as well as an S-92 civil cabin mockup at the United Technologies display.

By Paul Richfield