Space Shuttle Orbiter

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The Space Shuttle Orbiter is the orbital vehicle of the Space Shuttle. It is a reusable winged "spaceplane", a mixture of rocket, spacecraft, and airplane. The orbiter launches crew and payload into Earth orbit, performing on-orbit operations, then re-enters the atmosphere and lands like a glider to return the crew and any payload on board.

The orbiter carries most of the main propulsion system for reusable purpose, but the propellant for the three main engines is fed by an External Tank, and two solid rocket boosters help to propel it during the first two minutes of ascent.

Contents 1 Description 2 Specifications 3 Fleet 4 Flight statistics 5 See also 6 References 7 External links

[edit] Description

The Orbiter resembles an aircraft with double-delta wings, swept 81° at the inner leading edge and 45° at the outer leading edge. Its vertical stabilizer's leading edge is swept back at a 45° angle. The four elevons, mounted at the trailing edge of the wings, and the rudder/speed brake, attached at the trailing edge of the stabilizer, with the body flap, control the Orbiter during descent and landing.

The Orbiter's crew cabin consists of three levels: the flight deck, the mid-deck, and the utility area. The upper-most is the flight deck which seats the commander and pilot, with two mission specialists behind them. The mid-deck, which is below the flight deck, has three more seats for the rest of the crew members. The galley, toilet, sleep locations, storage lockers, and the side hatch for entering/exiting the vehicle are also located on the mid-deck, as is the airlock hatch. The airlock has another hatch into the payload bay. It allows two astronauts, wearing their Extravehicular Mobility Unit (EMU) space suits, to depressurize before a space walk.

The Orbiter has a large 60 by 15 ft (18 m by 4.6 m) payload bay, filling most of the midfuselage. The payload bay doors have heat radiators mounted on their inner surfaces, and so are kept open for thermal control while the Shuttle is in orbit. Thermal control is also maintained by adjusting the orientation of the Shuttle relative to Earth and Sun. Inside the payload bay is the Remote Manipulator System, also known as the Canadarm, a robot arm used to retrieve and deploy payloads. Until the loss of Columbia, the Canadarm had been used only on those missions where it was needed. Since the arm is a crucial part of the Thermal Protection Inspection procedures now required for Shuttle flights, it will probably be included on all future flights.^{[citation needed]} Three fuel cells are located under the payload bay area. They consume onboard liquid oxygen and liquid hydrogen storages to generate all the electrical power for the vehicle from launch to landing.

Three Space Shuttle Main Engines (SSMEs) are mounted on the Orbiter's aft fuselage in a triangular pattern. The three engines can swivel 10.5 degrees up and down and 8.5 degrees from side to side during ascent to change the direction of their thrust and steer the Shuttle as well as push. The aft fuselage also houses three auxiliary power units. The APUs are hydrazine-fueled turbopumps to provide hydraulic pressure for the hydraulic system, which gimbals the three main engines, controls aerosurfaces, and deploys the landing gears.

The Orbital Maneuvering System (OMS) provides orbital maneuvers, including insertion, circularization, transfer, rendezvous, abort to orbit, and abort once around.

The Reaction Control System (RCS) provides attitude control and translation along the pitch, roll, and yaw axes during the flight phases of orbit insertion, orbit, and re-entry.

The Thermal Protection System (TPS) covers the outside of the Orbiter, protecting it from the cold soak of -121 °C (-250 °F) in space to the 1649 °C (3000 °F) heat of re-entry.

The orbiter structure is made primarily from aluminium alloy, although the engine thrust structure is made from titanium alloy.

[edit] Specifications

(for Endeavour, OV-105)

• Length: 122.17 ft (37.24 m)
• Wingspan: 78.06 ft (23.79 m)
• Height: 58.58 ft (17.25 m)
• Empty Weight: 151,205 lb (68,586.6 kg)
• Gross Liftoff Weight: 240,000 lb (109,000 kg)
• Maximum Landing Weight: 230,000 lb (104,000 kg)
• Main Engines: Three Rocketdyne Block 2 A SSMEs, each with a sea level thrust of 393,800 lbf (178,624 kgf / 1.75MN)
• Maximum Payload: 55,250 lb (25,061.4 kg)
• Payload Bay dimensions: 15 ft by 60 ft (4.6 m by 18.3 m)
• Operational Altitude: 100 to 520 nmi (185 to 1,000 km)
• Speed: 25,404 ft/s (7,743 m/s, 27,875 km/h, 17,321 mph)
• Crossrange: 1,085 nautical miles (2,009.4 km)
• Crew: 6-7 (Commander, Pilot, 4-5 Mission Specialists and/or Payload Specialists), 2 (Commander and Pilot) for minimum.

[edit] Fleet

Individual Orbiters are both named, in a manner similar to ships, and numbered, using the NASA Orbiter Vehicle Designation system. While all Orbiters are externally very similar, they have minor internal differences; new equipment is fitted on a rotating basis as they are maintained, and the newer Orbiters tend to be structurally lighter.

Test Articles
Number	Name	Notes
OV-098 (honorary)	Pathfinder	Orbiter Simulator for moving and handling tests
MPTA-098	N/A	Testbed for propulsion and fuel delivery systems
STA-099	N/A	Structural test article used for stress and thermal testing, later became Challenger
Orbiters
Number	Name	Notes
OV-099	Challenger	Destroyed after liftoff - January 28, 1986
OV-101	Enterprise	Used for approach and landing tests, not suitable for spaceflight
OV-102	Columbia	Destroyed during reentry February 1, 2003
OV-103	Discovery	First launched on August 30, 1984
OV-104	Atlantis	First launched on October 3, 1985
OV-105	Endeavour	First launched on May 7, 1992

• Enterprise was a prototype designed to test Space Shuttle behavior in atmospheric flight. It performed various performance tests from February 12, 1977 to October 26, 1977. Several times from the late 1970's to the mid-1980's NASA considered retrofitting it for space flight but because of a redesign during the Columbia's construction it was deemed too costly. As a prototype Space Shuttle, rocket engines or a proper heat shield were never installed. It is currently on display at the Smithsonian's newly-built National Air and Space Museum Steven F. Udvar-Hazy Center at Dulles International Airport, where it is the centerpiece of the space flight collection.
• Columbia first launched on April 12, 1981. On February 1, 2003, Columbia disintegrated during re-entry on its 28th mission.
• Challenger first launched on April 4, 1983. On January 28, 1986 it broke up 73 seconds after the launch of its 10th mission.
• Discovery first launched on August 30, 1984. It has flown 32 missions and is still operational today. It is due to be retired in 2010.
• Atlantis first launched on October 3, 1985. It has flown 26 missions and is still operational today. It is scheduled to be retired in 2008.
• Endeavour first launched on May 7, 1992. It has flown 19 missions and is still operational today. It is due to be retired in 2010.

In addition to the test articles and Orbiters produced for use in the Shuttle program, there are also various mockups on display throughout the world:

• Space Shuttle Explorer, a full scale replica of an Orbiter at the Kennedy Space Center visitor's complex
• Space Shuttle Adventure, a full scale mockup of an Orbiter mid-deck and flight deck at Space Center Houston

[edit] Flight statistics

Shuttle	Flight days	Orbits	Distance		Flights	Longest flight -days-	Crews	EVAs	Mir/ISS docking	Sat. dep. †
			mi	km
Columbia	300.74	4,808	125,204,911	201,497,772	28	17.66*	160	7	0 / 0	8
Challenger	62.41	995	25,803,940	41,527,416	10	8.23	60	6	0 / 0	10
Discovery	268.62	4,229	109,810,673	176,657,672	32	13.89	199	31	1 / 6	26
Atlantis	243.99	3,654	94,808,732	152,534,078	27	12.89	167	21	7 / 7	14
Endeavour	206.60	3,259	85,072,077	136,910,237	19	16.63	130	29	1 / 6	3
Total	1,082.36	16,945	440,700,333	709,127,175	116	17.66*	806	97	9 / 19	61

(as of November 6, 2006)

† Satellites deployed
* This was flight STS-80, during November 1996.

[edit] See also

• Space Shuttle program
• Space Shuttle
• Shuttle Buran
• Spaceplane
• Shuttle SRB
• Space Shuttle external tank

[edit] References

[edit] External links

• Orbiter Vehicles

v • d • e  Space Shuttle Program
	Main Articles: Space Shuttle program | Space Shuttle
	Components: Orbiter | SRB | External Tank | SSME | OMS | Crawler Transporter
	Orbiters: Enterprise | Columbia | Challenger | Discovery | Atlantis | Endeavour
	Launch Sites: Kennedy Space Center LC-39 | Vandenberg Air Force Base SLC-6
	Developments: Shuttle-Derived Launch Vehicle | Shuttle-C | Ares I | Ares V
	Test Articles: Pathfinder
	Misc: Missions | Cancelled Missions | Decision | Crews | Abort modes | In Fiction

v • d • e  Space Shuttles
	US Space Shuttle program Enterprise (atmospheric tests) Pathfinder (ground facilities tests) Columbia (destroyed 2003) Challenger (destroyed 1986) Discovery (active) Atlantis (active) Endeavour (active)	Soviet Buran program OK-GLI (BST-02) (aerotester) Buran (retired, destroyed 2002) Ptichka (95–97% completed, unused) 2.01 (incomplete) 2.02 (partially dismantled) 2.03 (dismantled)