project project code given heavily classified manned reconnaissance aircraft studied cia potential replacements lockheed mid 1960s proposal high altitude plane fly considered insufficient advancement existing aircraft second advanced design referred air launched rocket powered boost aircraft use high altitude trajectory avoid defenses aircraft considered costly development project abandoned origins project developed result vulnerability existing manned reconnaissance aircraft lockheed lockheed soviet air defenses early 1960s shooting continuing plans soviet_union referred cia failed come pass cia began plans aircraft superior performance replace proposal initial aircraft proposed developed division developed work fish programs work tactical bomber design utilised systems developed use intended capable cruising speeds altitude feasibility study conducted completed fall aircraft determined costly considered potentially vulnerable projected soviet air defense capabilities project halted proposal design development alternative design completed usually considered documents refer aircraft having proposed boost aircraft submitted cia independently proposals featured small manned rocket powered craft high lift drag ratio air launched bomber flying atlantic_ocean aircraft rocket engine adopt trajectory soviet_union speeds altitude feet descending pacific_ocean landing groom lake nevada landing lake bed landing gear concept considered superior spy satellites number ways including rapid turnaround time quick response capability little funding cia budget developed aircraft funds technical support supplied cia proposal shape remains classified described similar space shuttle albeit reduced size cross model aircraft constructed illustrate principles construction showed aircraft essentially existing projected air defenses surface air missiles armed nuclear better force aircraft change course avoid fringe effects explosions cancellation following fourteen months work developed aircraft point proposals construction cia official requirement aircraft addition projected cost aircraft astronomical cost aircraft projected billion usd dollars inflation adjusted billion sum considered far high available budget addition concerns aircraft trajectory mistaken incoming missile cia failed receive approval funding approached project air_force proved adopting cia project despite support general chief late project terminated brief effort revive project proving unsuccessful engine development development aircraft conducted funding united_states_air_force fund development aircraft intended engine intended rocket engine powered liquid hydrogen liquid oxygen producing lbf thrust throttle development continued cancellation considered use space shuttle cancelled early 1970s
Project Isinglass