The Boeing B47 Stratojet first flown in 1947 was the first jet powered bomber, using air to air refueling, with the resulting intercontinental capability. Equipped with six General Electric J47-GE-11 jet engines that produced a total of 32,700 Ibs. static thrust not installed on the aircraft or 27,600 Ib. installed as well as the J47-GE-25 jet engine which produced 36,360 Ibs. static thrust not installed. The B47 fell short of being able to take off fully loaded (fuel and "the bomb") from most of the conventional runways in use at the time. Although this paper will concentrate primarily on the liquid rocket YLR45-AJ-1 installation, the solid rocket installations will be of interest for the purpose of comparison of performance. One configuration employed for the solid rocket installation was comprised of eighteen solid rockets mounted internally in the fuselage just above the aft tandem landing gear. These solid propellant rockets provided a total assist thrust of 18000 Ibs. A second solid rocket configuration consisted of thirty three units mounted on a jettisonable horsecollar yoke just aft of the rear tandem landing gear. This installation produced 33,000 Ibs. thrust. A third installation was comprised of thirty solid rockets mounted on a modified frame which when jettisoned would be more positively guided away from the aft fuselage. The solid rockets provided thrust for only 15 seconds and had a very smoky exhaust hi that they utilized potassium perchlorate and asphalt based propellants. As a result, on a still day the smoke would obscure the vision of the following airplanes during take-off. Additionally the solid rockets did not permit the execution of an aborted take-off as they would continue to produce full thrust until the propellants were expended. These three major shortcomings, the very short duration of the assist thrust and the generation of a large smoke cloud and failure to accommodate an aborted take-off made the relatively smokeless and longer duration (60 sec. duration) liquid rocket installation look more attractive as a long term solution. Contracts were awarded to Aerojet Engineering Corporation and the W. M. Kellogg Co. hi 1948 to develop a liquid rocket ATO utilizing white fuming nitric acid (WFNA) and JP-3 as propellants. The Kellogg effort was terminated hi 1951. The Aerojet program continued to the completion of development of a prototype unit that was qualified for flight and ultimately flight tested. The program was terminated at the completion of the flight test program on the B-47 airplane at Edwards AhForce Base in August 1954.