Accession Number : ADA426594


Title :   Performance Study of Two-Stage-To-Orbit Reusable Launch Vehicle Propulsion Alternatives


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS


Personal Author(s) : Brock, Marc A.


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA426594


Report Date : MAR 2004


Pagination or Media Count : 110


Abstract : This study investigated the performance of five Two-Stage-To-Orbit reusable launch vehicles (RLV), with stages propelled by rocket engines, turbojet engines and Rocket Based Combined Cycle (RBCC) engines. Horizontal versus vertical takeoff launch and direct versus lifting ascent trajectories were also studied. A method was conceived using a 3 degree of freedom optimization program, stage inert mass fractions, and a fixed gross takeoff weight (GTOW) of 1,000,000 lbf to determine each RLVs performance based on payload weight delivered to orbit and total vehicle inert weight. RLV trajectory constraints, mass fractions, engine performance, and aerodynamics were assumed from literature of similar RLVs or data provided by the Air Force Research Laboratory (AFRL). The method devised accurately predicted performance for all RLVs studied, but was time intensive and intolerant of small trajectory modifications. A horizontal takeoff RLV with the 1st stage powered by turbojet engines and the 2nd stage propelled by a rocket engine, in a lifting ascent trajectory, provided 3 times the payload weight to orbit when compared to the same vehicle in a vertical takeoff mode. The RLV with both stages propelled by rocket engines lifted more payload weight into orbit with a lower inert weight than all other RLVs studied. RLVs propelled by RBCC engines, on a direct ascent trajectory, had insufficient fuel to reach orbit because of the high inert weight of the RBCC engines.


Descriptors :   *PROPULSION SYSTEMS , *LAUNCH VEHICLES , ORBITS , PAYLOAD , AIR FORCE RESEARCH , PERFORMANCE(ENGINEERING) , THESES , FUELS , VERTICAL ORIENTATION , WEIGHT , TAKEOFF , LAUNCHING , ENGINES , AIR FORCE FACILITIES , HORIZONTAL ORIENTATION , LIFT , TRAJECTORIES , ROCKET ENGINES , AERODYNAMICS , TURBOJET ENGINES , ASCENT TRAJECTORIES.


Subject Categories : JET AND GAS TURBINE ENGINES
      ROCKET ENGINES
      UNMANNED SPACECRAFT


Distribution Statement : APPROVED FOR PUBLIC RELEASE