TYPE: High technology testbed (HTTB) conversion of L-100-20.

PROGRAMME: First flight of prototype N130X 19 June 1984; early trials described in 1989-90 and earlier Jane's; 3,915 kW (5,250 shp) Allison T56 Series IV engines with 4.19 m (13 ft 9 in) Hamilton Standard propellers installed by LASC first quarter of 1989 to improve field performance and terrain following; trials demonstrating 460 m (1,509 ft) take-off and 365 m (1,198 ft) landing at 59,000 kg (130,073 lb) weight began November 1989.

DESIGN FEATURES: HTTB intended for STOL flight research in avionic systems, advanced flight controls, flight deck displays, navigation, guidance and en route survivability systems for future tactical transports; external features include long dorsal fin, 'horsals' (horizontal dorsals) ahead of tailplanes, composite material sensor booms at wingtips and greatly enlarged flaps; undercarriage reinforced for high-sink landings; non-Lockheed pilots and flight engineers have flown aircraft at each modification stage to accumulate opinions and assessments.

FLYING CONTROLS: Control system extensively adapted to simplify achievement of autonomous short field operation in all visibility conditions.

STRUCTURE: As C-130H, but extensively reinforced.