training to reduce loss-of-control, involving full stalls, fully inverted flight, and 20-40° descents in a 2.8g envelope, within its 3g rating. Al-Qaeda use Between 1993 and 1994, Osama bin Laden reportedly owned and used a former USAF T-39A, which had been converted to civilian use and refurbished at Van Nuys Airport. An Egyptian pilot and bin Laden proxy, Essam al-Ridi, lawfully purchased the aircraft from a U.S. broker in California in 1992, claiming to represent wealthy Egyptians. Al Ridi reported to have personally delivered the plane to bin Laden—who was then exiled in Khartoum, Sudan—in January 1993. There, the jet was reportedly used to ferry five Al-Qaeda operatives to Kenya to agitate tribal insurgency against US peacekeeping troops in nearby Somalia; one of the passengers was allegedly senior bin Laden deputy Mohammed Atef. More than a year later, around October 1994, the jet overran the runway in Khartoum Airport and crashed into a sand dune. The aircraft was badly damaged and subsequently abandoned due to high anticipated repair costs; both al Ridi and Al-Qaeda-trained pilot Ihab Mohammad Ali separately claimed to have been at the controls (the aircraft is fitted with dual controls). In later years, Ali testified that, in 1995, bin Laden asked him to ram the plane against that of Egyptian president Hosni Mubarak, despite the aircraft having never been repaired after the Khartoum accident. Variants Civilian Sabreliner (NA-265 or NA-246) Prototype powered by two General Electric J85-GE-X turbojet engines, one built sometimes unofficially called XT-39. Sabreliner 40 (NA-265-40 or NA-282) Civil production variant for 11 passengers powered by two Pratt & Whitney JT12A-6A or -8 engines, two cabin windows each side; 65 built. Sabreliner 40A A Sabreliner marketing version of the Sabre 40 with lighter avionics similar to the Aero Commander, also produced by Rockwell International at the time. In addition to the lighter avionics package, the interior was redesigned for lighter construction. Sabreliner 50 (NA-265-50 or NA-287) One built in 1964 as a Model 60 with Pratt & Whitney JT12A engines, experimental platform for radome nose cowling. Sabreliner 60 (NA-265-60 or NA-306) Stretched Model 40 for 12 passengers with two Pratt & Whitney JT12A-8 engines, five cabin windows each side, 130 built. Sabreliner 60A Series 60 with Mark V super-critical wing. Sabreliner 65 (NA-265-65 or NA-465) Based on the Series 60 with Garrett AiResearch TFE731-3R-1D engines and new Mark V super-critical wing, 76 built. Sabreliner 75