The Space Shuttle the Space Processing the Shuttle and Shuttle for Flight
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The Space Shuttle The Space Processing the Shuttle and Shuttle for Flight Its Operations Flight Operations Extravehicular Activity Operations and Advancements Shuttle Builds the International Space Station The Space Shuttle and Its Operations 53 The Space The Space Shuttle design was remarkable. The idea of “wings in orbit” took concrete shape in the brilliant minds of NASA engineers, and Shuttle the result was the most innovative, elegant, versatile, and highly functional vehicle of its time. The shuttle was indeed an engineering Roberto Galvez marvel on many counts. Accomplishing these feats required the design Stephen Gaylor of a very complex system. Charles Young Nancy Patrick In several ways, the shuttle combined unique attributes not witnessed Dexer Johnson in spacecraft of an earlier era. The shuttle was capable of launching Jose Ruiz like a rocket, reentering Eart h’s atmosphere like a capsule, and flying like a glider for a runway landing. It could rendezvous and dock precisely, and serve as a platform for scientific research within a range of disciplines that included biotechnology and radar mapping. The shuttle also performed satellite launches and repairs, bestowing an almost “perpetual yout h” upon the Hubble Space Telescope through refurbishments. The most impressive product that resulted from the shuttl e’s capabilities and contributions is the International Space Station—a massive engineering assembly and construction undertaking in space. No other crewed spacecraft to date has replicated these capabilities. The shuttle has left an indelible mark on our society and culture, and will remain an icon of space exploration for decades to come. 54 The Space Shuttle and Its Operations What Was the winged vehicle for cross-range platforms, interplanetary probes, capability for re-entry into Earth’s Department of Defense payloads, and Space Shuttle? atmosphere and the ability to land a components/modules for the assembly heavyweight payload. of the International Space Station (ISS). Physical Characteristics These four components provided the The shuttle lift capability or payload The Space Shuttle was the most shuttle with the ability to accomplish decreased with increased operational complex space vehicle design of its a diverse set of missions over its altitude or orbit inclination because time. It was comprised of four main flight history. The Orbiter’s heavy more fuel was required to reach the components: the External Tank (ET); cargo/payload carrying capability, along higher altitude or inclination. with the crew habitability and three Space Shuttle Main Engines; Shuttle lift capability was also limited flexibility to operate in space, made two Solid Rocket Boosters (SRBs); by total vehicle landing weight— this vehicle unique. Because of its lift and the Orbiter vehicle. It was the different limits for different cases capability and due-East inclination, the first side-mounted space system (nominal or abort landing). An abort shuttle was able to launch a multitude dictated by the need to have a large landing was required if a system failure of satellites, Spacelab modules, science Space Shuttle Launch Configuration Orbiter ExternalExternal TankTank Space Shuttle Main Engine SoSolid Rocket Boosterer The Space Shuttle and Its Operations 55 during ascent caused the shuttle not to a landing speed of about 346 km/hr liquid hydrogen and the other for the have enough energy to reach orbit or (21 5 mph) was 1 hour and 5 minutes. storage of liquid oxygen. The hydrogen was a hazard to crew or mission. Abort tank, which was the bigger of the two During re-entry, the Orbiter was landing sites were located around the internal tanks, held 102,737 kg essentially a glider. It did not have world, with the prime abort landing sites (226,497 pounds) of hydrogen. The any propulsion capability, except for being Kennedy Space Center (KSC) in oxygen tank, located at the top of the the Reaction Control System thrusters Florida, Dryden Flight Research Center ET, held 61 9,1 60 kg (1 ,365, 01 0 pounds) required for roll control to adjust its on the Edwards Air Force Base in of oxygen. Both tanks provided the fuel trajectory early during re-entry. California, and Europe. to the main engines required to provide Management of the Orbiter energy the thrust for the vehicle to achieve a The entire shuttle vehicle, fully from its orbital speed was critical safe orbit. During powered flight and loaded, weighed about 2 million kg to allow the Orbiter to reach its ascent to orbit, the ET provided about (4.4 million pounds) and required a desired runway target. The Orbiter’s 180,000 L/min (47,000 gal/min) of combined thrust of about 35 million limited cross-range capability of about hydrogen and about 67,000 L/min newtons (7.8 million pounds-force) 1,480 km (800 nautical miles) made (1 8,000 gal/min) of oxygen to all three to reach orbital altitude. Thrust was management of the energy during Space Shuttle Main Engines with a provided by the boosters for the first final phases of re-entry close to the 6-to -1 mixture ratio of liquid hydrogen 2 minutes and the main engines for ground—otherwise called terminal to liquid oxygen. the approximately 8 minutes and area energy management—critical 30 seconds ascent required for the for a safe landing. vehicle to reach orbital speed at the Solid Rocket Boosters requisite altitude range of 185 to about The Orbiter performed as a glider 590 km (1 00 to 320 nautical miles). during re-entry, thus its mass properties The two SRBs provided the main had to be well understood to ensure that thrust to lift the shuttle off the launch Once in orbit, the Orbital Maneuvering the Flight Control System could control pad. Each booster provided about System engines and Reaction Control the vehicle and reach the required 14.7 meganewtons (3,300,000 System thrusters were used to perform landing site with the right amount of pounds-force) of thrust at launch, and all orbital operations, Orbiter energy for landing. One of the critical they were only ignited once the three maneuvers, and deorbit. Re-entry components of its aerodynamic flight main engines reached the required required orbital velocity decelerations was to ensure that the Orbiter center of 104.5% thrust level for launch. of about 330 km/hr (204 mph) gravity was correctly calculated and Once the SRBs were ignited, they depending on orbital altitude, which entered into the Orbiter flight design provided about 72% of the thrust caused the Orbiter to slow and fall process. Because of the tight center of required of the entire shuttle at liftoff back to Earth. gravity constraints, the cargo bay and through the first stage, which The Orbiter Thermal Protection System, payloads were placed in the necessary ended at SRB separation. which covered the entire vehicle, cargo bay location to protect the down The SRB thrust vector control system provided the protection needed to weight and center of gravity of the enabled the nozzles to rotate, allowing survive the extreme high temperatures Orbiter for landing. Considering the the entire shuttle to maneuver to the experienced during re-entry. Primarily Orbiter’s size, the center of gravity box required ascent trajectory during friction between the Orbiter and the was only 91 cm (36 in.) long, 5 cm first stage. Two minutes after launch, Earth’s atmosphere generated (2 in.) wide, and 5 cm (2 in.) high. the spent SRBs were jettisoned, temperatures ranging from 927°C having taken the vehicle to an altitude (1 ,700°F) to 1,600°C (3,000°F). The External Tank of about 45 km (28 miles). Not only highest temperatures experienced were were the boosters reusable, they were on the wing leading edge and nose cone. The ET was 46.8 m (1 53.6 ft) in length also the largest solid propellant motors The time it took the Orbiter to start with a diameter of 8.4 m (27.6 ft), in use then. Each measured about its descent from orbital velocity of which made it the largest component 45.4 m (1 49 ft) long and about 3.6 m about 28 ,1 60 km/hr (1 7,500 mph) to of the shuttle. The ET contained two (1 2 ft) in diameter. internal tanks—one for the storage of 56 The Space Shuttle and Its Operations External Tank Liquid Oxygen Feedline Liquid Hydrogen Tank Anti-vortex Repressurization Line Bafes Liquid Oxygen Tank Repressurization Line Liquid Hydrogen Tank Internal Stringers Solid Rocket Booster Forward Attachment Inter Tank Anti-slosh Bafes Gaseous Oxygen Vent Valve and Liquid Oxygen Tank Fairing Solid Rocket Boosters Forward Booster Separation Motors Frustum Nose Cap Forward Skirt (pilot and drogue parachutes) Igniter/Safe and Arm Three Main Parachutes Forward Segment With Igniter Avionics Forward-Center Segment Aft-Center Segment Avionics Three Aft Attach Struts Systems Tunnel (External Tank attach ring) Aft Segment With Nozzle Aft Booster Case Stiffener Rings Separation Motor Thrust Vector Actuators Aft Exit Cone Aft Skirt The Space Shuttle and Its Operations 57 Space Shuttle Main Engines (492,000 pounds-force) at vacuum machinery comprised of high- and throughout the entire 8 minutes and low-pressure fuel and oxidizer pumps, After SRB separation, the main engines 30 seconds of powered flight. The engine controllers, valves, etc. The provided the majority of thrust required engine nozzle by itself was 2.9 m engines were under constant control for the shuttle to reach orbital velocity. (9.4 ft) long with a nozzle exit diameter by the main engine controllers. These Each main engine weighed about of 2.4 m (7.8 ft). Due to the high heat consisted of an electronics package 3,200 kg (7,000 pounds).