Lockheed JF-104A (AF56-745A Tail No. 60745) Starfighter airplane piloted by Fred Drinkwater  conducted flight testing that demonstrated steep approaches that were ultimately used by the space shuttle.  Steep descent testing, including power-off landing approaches and demonstration of minimum lift-to-drag ratio (L/D) landings came out of the interest in the use of low L/D lifting bodies for recovery to landing from space. Note:  Used in publication in Flight Research at Ames;  57 Years of Development and Validation of Aeronautical Technology NASA SP-1998-3300 fig 93 ARC-1959-A-24953
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