"6_2_9_2.TXT" (11989 bytes) was created on 02-21-89 SPACE SHUTTLE STATISTICS N A S A EDUCATIONAL BRIEFS For The Classroom The Space Shuttle is NASA's first true aerospace vehicle. It takes off like a rocket, operate in orbit as a spacecraft, and land on the Earth as an airplane. The Shuttle is a four part vehicle consisting of the Orbiter, an expendable External Tank (ET), and two Solid Rocket Boosters (SRB's). Launched in a conventional manner, the Space Shuttle's Main Engines (SSME's) and the SRB's produce approximately 30,800,000 newtons of thrust. At 45 kilometers above the Earth the boosters separate and return to the Earth by parachute for sea recovery. Eight minutes into the flight, at an approximate altitude of 110 kilometers, the ET propellants are exhausted. The tank will separate from the Orbiter and disintegrate upon reentry into the Earth's atmosphere. Any surviving pieces fall into remote ocean areas. To complete orbital insertion to altitudes between 160 and 1110 kilometers, and later to make orbital adjustments, two Orbiter Manuvering System (OMS) engines fire. Once in space, the Space Shuttle Orbiter serves as a base to deploy payloads such as satellites or space probes. Satellites needing repair or servicing can be brought on board and later released or returned to Earth. The Orbiter can also be used as a platform for scientific research. At the completion of the orbital phase of the mission, the Orbiter is rotated in space by firing combinations of small rockets called the Reaction Control System (RCS). When the OMS engines are aimed in the direction of motion, they fire and the resulting thrust slows the Orbiter, initiating reentry. Before making atmospheric contact, the Orbiter is again rotated so that the underside will experience the major share of atmospheric friction. To protect the Orbiter, three types of reusable surface insulation are used. In areas of greatest heating, the nose area, and leading edges of the wings, reinforced carbon is used (carbon cloth impregnated with additional carbon, heat treated, and then coated with silicon carbide). Other areas are covered with thermal tiles made of silica fibers or a Nomex felt blanket material (nylon felt coated with silicon). To aid in heat rejection, the tiles are given a glassy ceramic coating. As the altitude and speed of the orbiter decreases, the Orbiter begins to function as a glider. The glide angle to the runway is about six times steeper than a commercial jet liner on landing approach. Landing speeds are approximately 340 kilometers per hour. Following landing, the Orbiter undergoes refurbishment, new payloads are inserted, a new External Tank installed, the booster refueled and the entire vehicle assembly is made ready for a new launch a few months later. To reduce costs, the Orbiter is designed to be used again for up to 80 missions and the SRB's are designed for about 6 flights each. S O L I D R O C K E T B O O S T E R S The SRB's provide the major portion of the thrust at the time of liftoff. They are the largest solid rocket boosters ever built, the first to be used to launch humans into space, and the first designed for reuse. The SRB's are assembled out of four tubular segments of 1.25 centimeter steel. The fore end is capped with a nose cone containing a parachute assembly. The aft end has a steerable nozzle. Eight small rocket motors, four in the nose and four in the aft, are used, at burn out, to separate the SRB's from the external tank. Each booster contains a solid propellant that looks and feels like the hard rubber of a typewriter eraser. A hollow core runs the entire length of the propellant load. To ignite the propellants, a small rocket motor, fixed at the fore end of the core, is fired first. Flames from the small rocket spread across the entire face of the core and the SRB's come to full thrust in less than one-half second. S T A T I S T I C S Length .................................... 45.46 meters Diameter ................................... 3.70 meters Mass empty ................................. 82,879 kilograms each Propellant Mass ............................ 503,627 kilograms each Thrust.................................... 12,899,200 newtons each at sea level Nozzles...................................Covergent-divergent. All- axis gimbaling of 8 degrees. Propellant Composition....................Aluminum perchlorate powder (oxidizer) ....................Aluminum powder (fuel) ....................Iron oxide (catalyst) ....................Polymer (binder and fuel) ....................Epoxy curing agent SRB Surface Insulation....................Ablative E X T E R N A L T A N K The external tank contains the propellants used for liftoff and ascent by the Shuttle Orbiter's three main engines. The ET has an external shell which encloses three inner tanks. The forward inner tank contains liquid oxygen under pressure. An unpressurized intertank holds most of the electrical components. The aft inner tank contains liquid hydrogen under pressure. Tank walls are manufactured of aluminum alloys and are up to 5.23 centimeters thick. Antivortex and antislosh baffles are built inside the fore and aft tank walls to dampen any motions of the liquid propellants that might throw the Shuttle off course. Propellants are fed to the Orbiters SSME's by gas pressure derived from the controlled boiling of the propellants. Following the depletion of the liquid propellants. Following the depletion of liquid propellants, the ET is destroyed on atmospheric reentry. S T A T I S T I C S Length ..................................... 47 meters Diameter.................................... 8.38 meters Mass empty.................................. 37,452 kilograms Propellants................................. Liquid oxygen (LO2) ................................. Liquid hydrogen (LH2) Propellant mass ............................. LO2--609,195 kilograms ............................. LH2--101,606 kilograms Propellant feed lines ...................... (2) 43 centimeters in diameter Propellant feed rate.................LO2--242,000 liters per minute .................LH2--184,420 liters per minute Surface insulation ................ 1.27 centimeters thick core/epoxy layer covered with a 2.54 centi- meter thick Spray-on foam. O R B I T E R The Space Shuttle Orbiter is a wide-body, delta-winged airplane and space vehicle. It is constructed primarily out of aluminum and covered with reusable surface insulation. The Orbiter is propelled by 49 rocket engines employed in various combinations for liftoff, attitude control in space, and in initiating reentry. Electrical power for Orbiter systems is provided by fuel cells which produce, as a byproduct, water for drinking. The heart of the Orbiter is the cargo bay which can carry up to four satellites for launching at one time. The cargo bay permits the science laboratory Spacelab, to be carried into space and returned to the Earth at the completion of a mission. A highly articulated mechanical arm called the Remote Manipulator System (RMS), can be operated by Shuttle astronauts while inside the Orbiter cabin. The arm will be used to extract payloads from the cargo bay and deploy them outside of the Orbiter. The forward section of the Orbiter contains the flight deck and crew quarters for the astronauts. During launch up to four astronauts may sit on the flight deck and up to three more may sit on the crew quarters deck. The forward portion of the flight deck resembles the cockpit of a jet liner but features separate controls for flying in space and flying in the atmosphere. The aft portion of the flight deck contains four stand-up duty stations including the controls for the RMS. The crew quarters deck is entered through an open hatch through the flight deck floor. The crew quarters contain eating, sleeping, and sanitary facilities. When extravehicular activities are necessary, an airlock is installed in the orbiter cargo bay and entry is gained through a hatch in the crew quarters. S T A T I S T I C S EXTERIOR DIMENSIONS Length.................................... 37.24 meters Body width................................ 6.9 meters Wingspan.................................. 23.79 meters Height with gear extended................. 17.27 meters Mass empty................................ 68,040 (Orbiter 102. Other orbiters have lower masses.) Cargo Bay length.......................... 18.28 meters Cargo Bay diameter........................ 4.57 meters Payload mass for launch................... 29,484 kilograms to low Earth orbit. Payload mass on return.................... 14,515 kilograms ENGINES SSME: 3 (Total) Liquid hydrogen and liquid oxygen propellants. Gambaling +/- 10.5 degrees on pitch axis and +/- 8.5 degrees on yaw axis. Thrust................................... 1,668,000 newtons each at sea level OMS 2 (Total) Nitrogen tetroxide (N2 O4) and monomethyl hydrazine (MMH) propellants Thrust.................................... 26,688 newtons in a vacuum RCS Primary Thrusters..........................38 (14 fore and 24 aft) N2 04 and MMH propellants Thrust.................................... 3,870 newtons each in a vacuum Vernier Thrusters..........................6 (2 fore and 4 aft) N2 04 and MMH propellants Thrust.....................................106 newtons each in a vacuum CREW QUARTERS..............................2 decks Cabin volume...............................71.5 meters (cubed) Atmosphere.................................normal Pressure...................................normal THERMAL PROTECTION SYSTEM..................Reusable RCC, coated silica tiles, and coated Nomex felt ---------------------------------------------------------------------- ACTIVITIES AND QUESTIONS FOR THE CLASSROOM 1. What are the four main parts of the Space Shuttle? 2. What is the major cost saving feature of the Space Shuttle over previous launch vehicles? 3. Describe the sequence of events for the Space Shuttle from launch to landing. 4. Compare the mass of the Space Shuttle empty to the mass of all propellants used to thrust it into space. Why is there such a difference between the two masses? 5. What is a newton of thrust in English system measurement? 6 Illustrate the size of the Orbiter by measuring and marking its outline on a large open area such as an athletic field or play- ground. 7. Why is the thrust for some rocket engines listed as "sea level" and for others as "vacuum"? 8. What is the volume of the cargo bay of the Orbiter? 9. Research previous launch vehicles and compare their sizes and payload capacities to the Space Shuttle. 10. What is the orbiter altitude range of the Space Shuttle? ---------------------------------------------------------------------- NASA EDUCATIONAL BRIEFS For The Classroom, EB-81-1 "6_2_9_3.TXT" (9813 bytes) was created on 10-29-92 NASA'S ORBITER FLEET COLUMBIA Columbia (OV 102), the first of NASA's orbiter fleet, was elivered to Kennedy Space Center in March l979. Columbia initiated the Space Shuttle flight program when t lifted off from Launch Complex 39's Pad A on April 12, 981. It proved the operational concept of a winged, eusable spaceship by successfully completing the Orbital light Test Program -- missions STS-1 through 4. Other achievements for Columbia include the first launch of satellites from a Space Shuttle (STS-5) and the first flight of the European-built scientific workshop -- Spacelab -- on mission STS-9. Columbia is named after a small sailing vessel that operated out of Boston in l792 and explored the mouth of the Columbia River. One of the first U.S. Navy ships to circum- navigate the globe was named Columbia. The command module for the Apollo 11 lunar mission was also named Columbia. DISCOVERY Discovery (OV 103), the third of NASA's fleet of reusable, winged spaceships, arrived at Kennedy Space Center in November 1983. (Challenger was the second orbiter to ar- rive at KSC. See "Challenger" for its history.) It was launched on its first mission, flight 41-D, on August 30, 1984, from Pad A. It carried aloft three communications satellites for deployment by its astronaut crew. Other Dis- covery milestones include the first dedicated Department of Defense mission, the first flight to retrieve and return disabled satellites to Earth for repair and the first Space Shuttle mission of the post-Challenger era. Discovery is named for two famous sailing ships; one sailed by Henry Hudson in 1610-11 to search for a northwest passage between the Atlantic and Pacific Oceans, and the other by James Cook on a voyage during which he discovered the Hawaiian Islands. ATLANTIS Atlantis (OV 104) was delivered to Kennedy Space Center in April 1985, as the fourth spaceship of NASA's orbiter fleet. Atlantis lifted off from Pad A on its maiden voyage on Oct. 3, 1985, on mission 51-J, the second dedicated Depart- ment of Defense flight. On its second mission, 61-B, Nov. 26, 1985, its astronaut crew conducted the first experiments for assembling erectable structures in space. Atlantis is named after a two-masted sailing ship that was operated for the Woods Hole Oceanographic Institute from 1930 to 1966. ENDEAVOUR Endeavour was the first ship commanded by James Cook, the 18th century British explorer, navigator and astronomer. In August 1768, on Endeavour's maiden voyage, Cook sailed to the South Pacific, around Tahiti, on a mission to observe and record the important and seldom occurring event when the planet Venus passes between Earth and the sun. Determining the transit of Venus allowed early astronomers to determine the distance of the sun from Earth. This distance then could be used as a unit of measurement essential in calculating the parameters of the universe. On June 3, 1769, Cook completed this mission and continued his voyage to explore the southern hemisphere. He discovered and charted New Zealand and surveyed the eastern coast of Australia and navigated the Great Barrier Reef. In addition, Cook's voyage on the Endeavour set a precedent of establishing the usefulness of sending scientists on voyages of exploration. Joseph Banks and Carl Solander, who sailed with Cook, became the first naturalists to examine plants and animals in an organized manner. The wealth of scientifically collected material was unique. They collected specimens from more than 100 new plant families with 800 to 1,000 new species. They also encountered hundreds of new species of animals. Cook also had astronomers and artists onboard. Endeavour and her crew made the first long-distance voyage on which no crewmen died from scurvy, the dietary disease caused by the lack of ascorbic acids. Cook is credited with being the first to use diet as a cure for scurvy, making his crew follow a strict diet that included cress, sauerkraut and an orange extract. He also ensured cleanliness and ventilation in the crew's quarters. The Endeavour was small, 368 tons, about 100-feet long and 20-feet wide. She had a round bluff bow and a flat bottom that provided uncommon spaciousness and helped prevent her from being torn apart by coral. However, in 1795, Endeavour ended her career on a reef along Rhode Island. Atlantis (OV 105) was delivered to Kennedy Space Center in May, 1991, as the fifth spaceship of NASA's orbiter fleet. Endeavour lifted off from Kennedy Space Center for the first time on May 7, 1992, on mission STS-49. MISSION The delta-winged orbiter resembles an airplane and is about the size of a DC-9 jetliner. It is launched into space like a conventional rocket while bolted to an external propellant tank and two solid rocket boosters. After liftoff, the boosters burn for a little over two minutes before being jettisoned and carried by parachutes to a watery landing. After splashdown, they are retrieved and returned to Kennedy Space Center for refurbishment. The orbiter's main engines continue to burn until about 8 1/2 minutes into the flight. After shutdown, the exter- nal tank is jettisoned, breaks up in the atmosphere, and falls into the Indian Ocean. It is the only piece of Shuttle flight hardware that is not reused. The orbiter then carries out its mission in space and returns to Earth like a glider. LAUNCH PROCESSING After completing a space mission, the orbiter is returned to Kennedy Space Center to undergo preparations for its next flight in a sophisticated aircraft-like hanger called the Orbiter Processing Facility (OPF). Here, the vehicle is safed, residual propellants are drained and any returning payloads are removed. Any problems that may have occurred with orbiter sys- tems and equipment on the previous mission are checked out and corrected. Equipment is repaired or replaced and extensively tested. Any modifications to the orbiter that are required for the next mission are also made in the OPF. Orbiter refurbishment operations and processing for the next mission also begin in the OPF. Large horizontal payloads, such as Spacelab, are installed in the orbiter cargo bay. Vertical payloads are installed at the launch pad. Following extensive testing and verification of all electrical and mechanical interfaces, the orbiter is trans- ferred to the nearby Vehicle Assembly Building where it is mated to the external tank and solid rocket boosters. Then, the assembled Space Shuttle vehicle is carried to the launch pad by a large tracked vehicle called the crawler- transporter. At the launch pad, final preflight and interface checks of the orbiter, its cargo and associated ground support equipment are conducted. After a positive Flight Readiness Review, the decision to launch is given and the final countdown begins. ORBITER MODIFICATIONS More than 200 significant modifications are being made to the orbiter fleet. These modifications involve orbiter main engines, brakes and landing gear, thermal protection system and propellant supply systems, as well as a new crew escape system. Main engine modifications include changes to the high- pressure turbomachinery, hydraulic actuators, and main combustion chamber. The orbiter braking system will be upgraded to increase braking capacity, improve steering, and reduce the effects of tire damage and failure. Additions to the system also in- clude tire pressure monitoring. Some of the tiles that make up the orbiter thermal protection system have been replaced with thermal blankets to make the system lighter, stronger and more durable. Also, a reinforced carbon-carbon panel will be added to the or- biter chin between the nose cap and the nose wheel door to provide improved insulation against the searing heat of reentry. Improvements to the orbiter propellant supply system in- clude a redesigned 17-inch quick disconnect valve between the orbiter and the external tank. Additional modifications will be made to the propellant systems of the orbiter reac- tion control system, orbital maneuvering system, and the auxiliary power units. A new crew escape system has been added that allows the Space Shuttle crew to bail out if the orbiter has to make an emergency return descent and a safe runway cannot be reached. This system consists of an escape pole that would be extended from the opened crew hatch. The crew would then fasten a lanyard hook assembly that is a part of the pole to their parachute harnesses. Once attached to this hook, the crew would slide down the deployed pole, away from the orbiter. Once free of the pole, they would parachute to safety. SPACE SHUTTLE Height: 184.2 feet Gross liftoff weight: 4,500,000 pounds Total liftoff thrust: 7,700,000 pounds ORBITER Length: 122.17 feet Wingspan: 78.06 feet Dry Weight: Columbia (OV 102) 178,000 pounds Discovery (OV-103) 171,000 pounds Atlantis (OV-104) 171,000 pounds Main Engines: (3) 375,000 pounds of thrust each (sea level) Cargo Bay: length - 60 feet diameter - 15 feet SOLID ROCKET BOOSTERS (2) Length: 149.16 feet Diameter: 12.17 feet Liftoff Weight: (each) 1,300,000 pounds Recovery weight: (each) 192,000 pounds Thrust: (each) 3,300,000 pounds (sea level) EXTERNAL TANK Length: 153.8 feet Diameter: 27.6 feet Weight: Liftoff: 1,655,600 pounds (535,000 gallons) Empty : 66,000 pounds Propellants Liquid Oxygen: Capacity: 143,351 gallons Volume: 19,600 cubic feet Liquid Hydrogen: Capacity: 385,265 gallons Volume: 53,500 cubic feet