Shuttle lifted off under the power of its
*** Two SRB (Solid propellant motor) had APCP (Ammonium Per chlorate Composite Propellant) & Three Main Engines, which were fueled by liquid Hydrogen and liquid Oxygen from ET (External Tank).
…… SRB gave the 83% of lift of thrust & 28, 00,000 pound force at sea level and 31, 00,000 pound force after liftoff.
…… At liftoff two SRB were used to take the vehicle to an altitude of roughly 1, 40,000 feet.
…… About two minutes after liftoff, explosive bolts were fired, releasing the SRBs, which then parachuted into ocean for reuse.
*** Orbiter and ET continued to ascent on an increasingly horizontal flight path under power from its main engines.
*** Upon reaching 17,500m.p.h, necessary for low earth orbit, the main engines were shut down then ET was jettisoned to burn up in the atmosphere.
*** After jettisoned ET, the OMS (Orbiter Maneuvering System) engines were used to adjust the orbit
…… OMS used the fuel MMH (Mono Methyl Hydrazine) & N2O4 (Nitrogen Tetra oxide), and it gave the 6,000lbf of thrust with specific impulse of 313seconds for about 1000 feet per seconds (300m/s).
…… OMS provided significant thrust for coarse orbital maneuvers including orbital injection, circulation, transfer, and rendezvous, de-orbit, abort to orbit and to abort once around.
…… Orbiter carried people & payload into Low Earth Orbit into earth’s upper atmosphere or thermosphere.
…… Typical payload Capacity was about 22,700kg (50,000lb), it could be increased depending on the choice of launch configuration.
…… Orbiter carried its payload in a large cargo bay with doors that opened along the length of its top.
*** After completed the space mission, it fired its OMS thrusters to drop out and while re-enter to the atmosphere, during descent, the orbiter passed through different layers of the atmosphere and decelerates from Hypersonic speed primarily by “Aero braking”.
…… Aero braking is a space flight maneuver resulting drag slows the spacecraft and it is used when a craft requires a low orbit after arriving at a body with an atmosphere, it requires less fuel than does the direct use of rocket engines.
…… While prepared to the re-entry they operated the orbiter nose-first and up-side-down, so only could fire the RCS thrusters to turn the orbiter tail-first and reduce speed to 200m.p.h (retro fire).
…… Now tail-first, fired the OMS engine to slow and fall down to earth and it done before 25minutes to reach earth’s upper atmosphere.
…… Up-side-down for the easy to turn the orbiter at 40 degree angle with bottom of orbiter face the atmosphere while enter the atmosphere at re-entry, now nose-first again and before reentry just fired left over fuel by RCS thruster to avoid explode of high heat re-entry.
…… At the re-entry altitude 129k.m (80 mile or 400,000 feet) from the earth surface and range from the landing site was 8047k.m (5000miles) and the speed while re-entry 17,000m.p.h (28,000k.m/h).
*** Landing Phase – In lower atmosphere, it was more like a glider with parachute & Fly-by-wire controlled hydraulic actuated flight surfaces controlling its descent.
…… Now no fuel was needed to slow down the orbiter after re-entered to atmosphere.
…… @ lower atmosphere, flight control surfaces were used to slow down the craft by S-shaped banging turns with horizontal landing.
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