USAF F-16A UCAV: In 1998 Lockheed Martin proposed the F-16A UCAV (Unmanned Combat Air Vehicle) Long Endurance Defender as a low-cost augmentation to the USAF F-16C fleet. Designed for extended endurance/loiter time, the F-16A UCAV would be armed with ground attack munitions and defensive air-to-air missiles. A major structural modification for the UCAV variant would replace the standard F-16 low aspect ratio wing with a 60 ft. high aspect ratio wing. Improved aerodynamics and approximately 22,000 lb. of fuel would potentially increase combat endurance up to eight hours or, at least three times the standard F-16. Other modifications include the removal of the canopy, seat, and cockpit displays and adding an additional 2,300 lb. fuel tank. In addition, the 20mm canon and ammunition drum would be removed to provide capacity for additional data link and communications equipment. To complete the conversion to a UCAV, off-the-shelf automatic landing flight controls and throttle systems would be added to the basic F-16A avionics. Lockheed Martin FY95 R&D cost estimated for the F-16A UCAV program were from $60-$90 million, and conversion estimates for 26 stored F-16 A-model aircraft from $3-$5 million per airframe. Extensive examination of the data concluded that although the unmanned variant was feasible however, other factors were considered. At the time, there were 20-years of technological improvements in the F-16 C-model over the F-16A slated for conversion. Additional F-16A airframe limitations included, incorporating advanced ordnance, avionics, and maintenance. The USAF F-16A UCAV program did not move forward. - Erik Simonsen