Artist's conception of two U.S. Marine Corps CH-53K helicopters, sling-loaded with two Humvees apiece, refueling from a KC-130 tanker / U.S. Navy image

By BRADLEY PENISTON • PARIS — The first ground-test model of the CH-53K heavy-lift helicopter is under construction, and the U.S. Navy effort is on track for first flight in 2014, a production decision in 2015, and initial operation in 2018, program officials said June 21.

Lead contractor Sikorsky, now under contract for the test vehicle and four aircraft, is currently negotiating the first low-rate initial production deal, said Sikorsky’s Dave Zack.

That schedule reflects last year’s decision to delay first flight by two years and IOC by three.

The centerpiece of the new variant is raw power: three GE38 turbine engines will develop 7,500 shaft horsepower, up from the 4,300 of the current CH-53E model. Test units had run for 444 hours through March, according to Navy briefing slides.

The new power plants will allow the K model to roughly double the payload of existing 53s, lofting 27,000 pounds 110 nautical miles.

The customer is the U.S. Marine Corps, which plans to buy 200 Ks to replace and then enlarge its heavy-lift fleet, said Marine Col. Robert Pridgen.

As for the U.S. Navy, which currently operates its own -53s for logistics work?

“The Navy has not decided on heavy lift,” Pridgen said.