Sikorsky is currently engaged in full system testing of the U.S. Marine Corps’ CH-53K heavy lift helicopter with all seven main rotor blades and four tail rotor blades attached for the first time to a non-flying prototype called the Ground Test Vehicle (GTV). Powered “Light-Off” with rotor blades spinning follows a “Bare Head” (without blades) test phase of the GTV aircraft’s systems powered by its three GE 7,500 horsepower class engines, and begins a rigorous two-year test program of the rotor blades, transmission, engines, and all subsystems while the GTV is anchored to the ground.
The GTV will play a key role for Sikorsky and the U.S. Marine Corps during hundreds of hours of powered ground tests as the CH-53K team prepares for first flight and the subsequent three-year flight test program. By accumulating operational experience ahead of the four flight test aircraft — currently in final assembly — the GTV can measure and verify the ability of the drive system, transmissions and engines to fly the CH-53K helicopter safely and efficiently across multiple flight scenarios up to its 88,000-pound (39,916 kg) maximum gross weight with an external load.
Sikorsky CH-53K GTV. Photo courtesy of Sikorsky
During the next 250 hours of operation, the GTV will continue to assess the helicopter’s subsystems and the structural integrity and whirl characteristics of the rotors, blades and drive train.
The first of the four flight test helicopters — known as Engineering Development Models — is scheduled to take to the skies in late 2014. During the three-year flight test program, each flight test aircraft is expected to accumulate approximately 500 flight test hours. To ensure safety of flight, the GTV will continue to accumulate hundreds of operational endurance hours ahead of the flight aircraft.
The Naval Air Systems Command gave the go-ahead for the powered tests in December following closure of actions from an October Test Readiness Review and the completion of sub-system qualification testing.
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