Press Releases

April 01, 2004

Modern digital control of the S-92 rotor ice
protection system provides improved aircraft
performance and greater safety.

The aircraft has completed over 80 percent of the test requirements for icing certification, and has begun natural icing trials with several successful natural icing events flown to date. The S-92 will seek out a wide range of natural icing conditions in the months ahead.

The Sikorsky team in Marquette, Michigan, used specialized equipment from the U.S. Army's Aviation Technical Test Center. A CH-47D Chinook icing tanker and a C-12G King Air-instrumented icing scout traveled from Fort Rucker, Ala., to Marquette to assist in the testing.

"The tanker tests validate the design capabilities of the main rotor and tail rotor ice protection system. The system behaved flawlessly in both continuous and intermittent maximum icing conditions," said Robert Flemming, Chief of Icing Technology for Sikorsky."

The tanker provides simulated test conditions throughout the test envelope required for icing certification, while the C-12G samples the cloud prior to the immersion of the helicopter confirming that the cloud satisfied certification conditions. Use of the icing tanker means that less time is required to collect validation data than if the aircraft were forced to seek natural icing conditions.

The C-12G also served as a photography platform for the test. Because the HISS cloud covers only the test helicopter, the test director can constantly monitor the operation and record a continuous video record of any ice accretion.

Modern digital control of the rotor ice protection system provides improved aircraft performance and greater safety. The S-92 is equipped with a full set of instrumentation for in-flight monitoring, and the recorded data can be processed further during post-test analysis. The digital control system is fully integrated into the S-92's glass cockpit and includes system monitoring and diagnostic capabilities.

Based on the thousands of deiced helicopters that Sikorsky has delivered in the past 30 years, the S-92 rotor deice system has heating elements in the rotor blades that are controlled by redundant computer systems and powered by redundant electrical generators. The system precisely times the power to the blades to automatically shed ice away from the main and tail rotor.

The S-92 deice system has already completed tests in West Palm Beach, Fla.; Stratford, Conn., and artificial icing tests while tied down with the rotor turning in the enormous environmental hangar facility at Elgin Air Force Base in Fort Walton Beach, Fla.

The S-92 previously completed cold weather, engine inlet and snow tests and is already certified for operation in these conditions.

Sikorsky Aircraft Corporation, based in Stratford, Conn., is a world leader in the design, manufacture and service of advanced helicopters for commercial, industrial and military uses. Sikorsky helicopters occupy a prominent position in

The icing tanker provides simulated test
conditions throughout the test envelope
required for icing certification.

Sikorsky is a subsidiary of United Technologies Corporation (NYSE:UTX), of Hartford, Conn., which provides a broad range of high-technology products and support services to the aerospace and building systems industries.