Sikorsky’s S-92 has successfully completed the artificial icing requirement of the FAA’s icing-certification program, thus preparing the aircraft for its final all-weather-operations certification phase. It has already completed more than 80 percent of the requirements for icing certification and begun natural icing trials, with several successful natural icing events flown to date.
A Sikorsky team in Marquette, Mich., 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 icing scout traveled from Fort Rucker, Ala., to Marquette to assist in the testing.
“The tests validated the design capabilities of the main rotor and tail-rotor ice-protection system,” said Robert Flemming, Sikorsky chief of icing technology. “The system behaved flawlessly in both continuous and intermittent maximum icing conditions.”
The tanker provides simulated conditions throughout the test envelope required for icing certification, while the C-12G samples the cloud before immersion of the helicopter, confirming that it satisfies certification conditions. Using a tanker means that validation data can be collected faster than if the aircraft were forced to seek natural icing conditions.
The C-12G also served as an aerial video/photography platform for the test. Because the artificially generated ice covers only the test aircraft, the test director can constantly monitor the operation and make 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.
The S-92 rotor de-ice system has computer-controlled heating elements in the rotor blades that are powered by redundant electrical generators. The system precisely delivers power to the blades to automatically shed ice away from the main and tail rotor.
The S-92 de-icing system has already completed tests in West Palm Beach, Fla., and Stratford, Conn., as well as rotors-turning artificial icing tests while tied down in an environmental hangar at Elgin Air Force Base in Fort Walton Beach, Fla.
The S-92 has also passed cold-weather engine-inlet icing and snow tests.