The weeklong initial operational assessment of the Sikorsky CH-53K King Stallion has been ruled a success by the U.S. Marine Corps, parent company Lockheed Martin said. Assessed by Marine pilots, aircrew and maintainers, the tests verified the helicopter’s key capabilities.

Tests included external-lift scenarios of 27,000 pounds in hover, a 12,000-pound nautical mile radius mission, embarkation and debarkation of combat-equipped troops, internal and external cargo rigging, tactical bulk fuel delivery system operation and medevac litter configuration. These tests were intended to minimize risk to successfully pass the Marine operational evaluation phase.

This operational assessment took place in West Palm Beach, Florida, at Lockheed’s Sikorsky Development Flight Center. This is wher all CH-53K flight tests have taken place, havin progressed with all four engineering development model aircraft in flight status. Customer assessment is a prerequisite to a low rate initial production Milestone C decision, which will take place early next year.

The first four of the contracted 200 heavy-lift aircraft are scheduled for delivery to the Marines next year. They will be produced in Sikorsky’s Stratford, Connecticut, facility.