Monday, October 22, 2012

RI Starraker SSTO concept

Star-Raker: An Airbreather/Rocket-Powered, Horizontal Takeoff Tridelta Flying Wing, Single-Stage-to-Orbit Transportation System – 1979 (7.12 MB PDF) Earth-to-LEO Transportation System for SPS – IRD Data Sheet (14.3 MB PDF) NASA CR 3321: Satellite Power Systems (SPS) Concept Definition Study – Volume IV: Transportation Analysis Excerpt (1~ MB PDF) NASA TM 58238: Satellite Power System: Concept Development and Evaluation Program – Volume VII: Space Transportation Excerpt (610 KB PDF) Photographs/Illustrations NOTE: The photographs along with two of the above references came packed in a 18 MB PDF (link here) that I received which used JPG compression. I extracted the images and saved them as PNG files to avoid any further generational artifacts from being introduced. Star-Raker Re-Entry Trajectory (2.04 MB PNG) Star-Raker in Orbit with a SPS (1.58 MB PNG) Star-Raker Comparison with a 747 (2.06 MB PNG) Star-Raker on Landing Approach (1.97 MB PNG) Star-Raker On the Ground Being Maintained (355.40 KB JPG) Star-Raker Launch Trajectory (2.23 MB PNG) Star-Raker cargo loading operations (2.07 MB PNG) Star-Raker in Orbit 1 (1.79 MB PNG) Star-Raker in Orbit 2 (221.87 KB JPG) Star-Raker Engine Cutaway Diagram (369.49 KB PNG) Basic Dimensions Length: 310 feet Reference Wing Area: 40,900 ft2 Handling Could land/take-off using runways 8,000 to 14,000 ft long (2,440 to 4,270 m). Takeoff velocity 225 knots or greater, landing velocity about 115 knots. Cargo Capabilities 200,000 lb maximum payload capacity in a 20 x 20 x 141.5 ft cargo bay (56,600 ft3) accessed via hinged nose. Could deliver 196,600 lbs to a 300 nautical mile @ 28.5 deg inclination orbit flying directly from Kennedy Space Center for a cost of $10 to $15 per pound ($30 to $45 per pound in 2010 dollars). Propulsion Ten hydrogen fueled high bypass supersonic turbofan/air-turbo-exchanger/ramjet engines, each with 140,000 lbf of thrust. Engine design to be based off the GE CJ805 axial flow turbojet, P&W SWAT 201 turbofanramjet, Aerojet Air Turborocket, Marquardt Variable Plug Nozzles, ramjet engines, and Rocketdyne tubular cooled rocket engines. Subsonic ISP of 9,700 seconds that linearly reduces to 4,000 seconds at 366 m/sec. Supersonic ISP that reduces from 4,000 seconds at 366 m/sec to 3,500 seconds at 1,700 m/sec. Three hydrogen fuelled rocket engines, each with 1.06 million lbf of thrust and an ISP of 455 seconds. Flight Profile A typical profile flown from Kennedy Space Center to a 300 n.mi orbit at 28.5 deg inclination was to be: Runway takeoff under high-pass turbofan/airturbo exchanger (ATE)/ramjet power, with the ramjets acting as supercharged afterburners. Jettison and parachute recovery of landing gear used only for launch. Climb to optimum cruise altitude with turbofan power. Cruise at optimum altitude, Mach number, and direction vector to earth's equatorial plane, using turbofan power. Execute a large-radius turn into the equatorial plane with turbofan power. Climb subsonically at optimum climb angle and velocity to an optimum altitude, using high bypass turbofan/ATE/ramjet (supercharged afterburner) power. Perform an optimum pitch-over into a nearly constant-energy (shallow Y_angle) dive if necessary, and accelerate through the transonic region to approximately Mach 1.2, using turbofan/ATE/ramjet (supercharged afterburner) power. Execute a long-radius optimum pitch-up to an optimum supersonic climb flight path, using turbofan/ATE/ramjet power. Climb to approximately 29 km (95 kft) altitude, and 1900 m/s (6200 fps) velocity, at optimum flight path angle and velocity, using proportional fuel-flow throttling from turbofan/ATE/ramjet, or full ramjet, as required to maximize total energy acquired per unit mass of fuel consumed as function of velocity and altitude. Ignite rocket engines to full required thrust level at 6200 fps and parallel burn with airbreathing engines to 7200 fps. Shut down airbreather engines while closing airbreather inlet ramps. Continue rocket power at full thrust. Insert into an equatorial elliptical orbit 91 x 556 km (50 x 300 nmi) along an optimum lift/drag/thrust flight profile. Shut down rocket engines and execute a Hohmann transfer to 556 km (300 nmi). Circularize Hohmann transfer. Release Payload or dock with Space Station at that orbit. Perform delta-v maneuver and insert into an equatorial elliptical orbit 91 x 556 km (50 x 300 nmi) in preparation for re-entry. Perform a low-gamma (flight path angle), high-alpha (angle of attack) re-entry deceleration profile very similar to Space Shuttle to approximately Mach 6. Reduce alpha (angle of attack) to appropriate angle for maximum lift/drag ratio for high speed glide and cross range maneuvers to subsonic velocity (Mach 0.85). Open inlets and start some airbreather engines. Perform powered flight to landing field, land on runway, and taxi to jetway. Flyback fuel requirements include approximately 300 nmi subsonic cruise and two landing approach maneuvers (first approach waveoff with flyaround for second approach). Mass Properties ITEM DESCRIPTION ROCKWELL/MSFC JOINT ESTIMATE (Masses are in pounds) Airframe, Aerosurfaces, Tanks and TPS 370,000 Landing Gear 27,700 Rocket Propulsion 71,700 Airbreather Propulsion 140,000 RCS Propulsion 10,000 OMS Propulsion 5,000 Other Systems 37,800 Subtotal 662,200 10% Growth Margin 66,220 Total Inert Weight (Dry Weight) 728,420 Useful Load (Fluids, Reserves. Etc.) 47,400 Inert Weight & Useful Load 775,820 Payload Weight 196,580 Orbital Insertion Weight 972,400 Propellant Ascent 4,027,600 GLOW (Post Jettison Launch Gear) 5,000,000 NOTES: Mission is to a 300 nautical mile, 28.5 degree orbit.

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