The tests, required by the U.S. Naval Air Systems, were conducted using a full-size, non-flying airframe called the Static Test Article.
"The Static Test Article will enable Sikorsky to replicate the many stresses, strains and aerodynamic forces the CH-53K helicopter will experience during all aspects of flight, whether the aircraft is empty, filled with cargo, or carrying up to 36,000 pounds of gear suspended beneath the aircraft by an external sling," said Mike Torok, Sikorsky's CH-53K program vice president.
"By placing incrementally heavier static loads on various parts of the airframe assembly -- including those well beyond the airframe's analytical design strength -- we can measure structural integrity, airworthiness and crash worthiness, and verify safety margins for all expected operational conditions," Torok said.
"The Static Test Article is composed of the cockpit, cabin, fuel sponsons, a transition section and the tail rotor pylon -- all suspended off the ground by the shaft of the aircraft’s main rotor gearbox. Surrounding support beams hold the numerous hydraulic cylinders that apply the flight and inertial loads to parts of the airframe assembly,” Sikorsky said.
Component-representative weights that simulate the presence of the engines and landing gear are also part of the configuration.
Six tests have been performed to date and testing will continue for another two years, the company said.
The CH-53K is a heavy-lift aircraft with a cruise speed of 196 miles per hour and a combat radius of 110 miles. The U.S. Marine Corps plans to procure some 200 CH-53Ks, which are expected to become operational in 2018.