An NTSB preliminary report posted yesterday provides details on a May 4 incident involving a Hawker 800A that went of control and lost more than 10,000 feet before recovering. N71MT, owned and operated by Raytheon Aircraft, was on a maintenance test flight and the crew was setting up for a stall series at 17,000 feet near Lincoln, Neb. The pilots calculated that the stick shaker would activate at 115 knots, the stick pusher at 107.5 knots and the stall at 105.5 knots. But as the airplane slowed through about 126 knots, “it abruptly rolled off, dropp[ing] the right wing, and the nose fell rapidly,” the pilot told the NTSB, adding that he felt “no vibration or abnormal indication.” The airplane rolled five to seven times to the right and the left. According to the pilot, the aircraft was “descending vertically” after breaking out of a shallow cloud layer at about 10,000 feet. “I neutralized the ailerons with the yoke and began a higher-than-normal back-pressure pull-out, experiencing [approximately] 4 to 5 gs. We stopped the descent somewhere below 7,000 feet.” The twinjet returned to Lincoln and made an uneventful no-flap landing. The two pilots and four passengers sustained minor injuries.