The NTSB is investigating the May 4 upset of a Raytheon Aircraft-owned Hawker 800A near Lincoln, Neb., during a post-maintenance stall test. At 17,000 feet, the Hawker’s right wing dropped, then the jet rolled right and left and lost more than 10,000 feet before the pilot pulled (he said) four to five gs, recovering at about 7,000 feet. The stall test, required after leading-edge panel replacement, must be done at 10,000 feet above clouds and with the autopilot disengaged. The pilot told the NTSB that the Hawker proceeded down through clouds at 12,000 feet and exited at 10,000 feet “descending vertically.” The pilot also said that the auto-pilot was engaged during the test. Four passengers were on board. On Sept. 20. 2003, an instructor and two pilots on a training mission were killed when their Hawker crashed near Beaumont, Texas, after it was stalled from 5,000 feet.