General Electric has launched tests on the first 7,500shp (5,590kW)-class GE38-1B engine, even as Sikorsky and the US Marine Corps begin to struggle with keeping the CH-53K airframe on schedule.

The USMC awarded a contract to Sikorsky in 2005 to build 205 CH-53Ks. The helicopter is designed to carry 12,200kg (27,000lb) for at least 200km (110nm) on a hot day, at least doubling the maximum payload of its CH-53D/Es. GE will supply 25 GE38-1B engines from 2011 to support the flight-test programme.

But Sikorsky has acknowledged that the deployment date for the first CH-53K operational unit has slipped to "early 2016". The initial operational capability (IOC) date was previously scheduled during fiscal year 2015.

"The CH-53K helicopter team has successfully conducted several risk reduction initiatives on two critical technologies: split torque main gear box and main rotor blade," Sikorsky says. The programme has also launched "many process and product improvement measures as a result", it adds.

USMC budget documents released in May also acknowledge a programme delay, but note that the problems fall short of exceeding "baseline parameters".

The next major development milestone for the CH-53K is the critical design review scheduled in the second quarter of FY2010.

Testing for the GE38-1B began on 24 June, meeting GE's plan to initiate tests during the first half of 2009. The design is expected to be the first of a family of new powerplants for helicopters and turboprops filling a projected demand for propulsion options in the 6,000-10,000shp range.

The company calls the GE38-1 "the cornerstone for a new engine family, with a revenue potential of more than $4 billion, including heavylift applications".

The CH-53K was among several USMC programmes unscathed in the recent Department of Defense budget cutting proposals. However, Secretary of Defense Robert Gates has said that the service's acquisition portfolio will be looked at as part of the Quadrennial Defense Review.

Source: Flight International