Operating the World's Most Versatile Launch System
Once again, NASA and the nation are beginning the long process of returning to flight, following the Space Shuttle Columbia accident. With an unwavering commitment to the Columbia crew families, the NASA family and the Nation, NASA will safely return to flight and continue its mission of the human exploration of space. The Space Shuttle has and will continue to enable human access to space and the assembly and re-supply of the International Space Station. The Shuttle Service Life Extension Program began in the fall of 2002 will move forward; although, the focus of this effort may be affected by return to flight decisions. SLEP was designed to assess what the Shuttle program needs to do to assure Space Shuttle access to space through the end of the next decade. The recent missions and future expectations of the Space Shuttle are highlighted in this fact sheet.
The Space Shuttle's current primary mission, to assemble and supply the International Space Station, will move forward as soon as possible. However, while the Space Shuttle fleet is preparing to return to flight, the assembly of the Space Station is on hold. Through cooperation among members of the Space Station international partnership, re-supply and crew exchange will be accomplished with Russian Progress and Soyuz missions, respectively.
In flight for over 21 years, the Shuttle remains the world’s most versatile spacecraft, capable of activities ranging from satellite deployment, maintenance, repair and retrieval; to Space Station assembly and support; to research in orbit. As NASA works toward improving the safety of the Shuttle, this tradition will continue. The flights completed in 2002 to assemble and re-supply the Space Station and enable Station crew rotation were all notable mission successes.
There are three Space Shuttle main engines on each orbiter and each of those SSMEs can generate 375,000 pounds of thrust operating at 100% power.
At full power, the SSMEs generate, in watts, the equivalent of 23 Hoover Dams.
One SSME has sufficient thrust to power 2 ½ 747s.
The flow of fuel from the External Tank to the three SSMEs during launch is equal to draining an average swimming pool in 25 seconds. The pressure the pumps operate under is equal to that of a submarine three miles deep.
The full power of the high-pressure fuel and oxidizer pumps from two SSMEs is more than enough to operate a 91,700-ton Nimitz-class aircraft carrier at cruise speed. If all three pump sets were combined, they would have sufficient “oomph” to propel the Battleship New Jersey, with enough power left over to propel 12 Ethan Allen-class submarines.
There are two Solid Rocket Boosters used during each launch, and together they generate 5.3 million pounds of thrust at launch.
The combined thrust of 5.3 million pounds is equal to 44 million horsepower, or 14,700 six-axle diesel locomotives, or 400,000 subcompact cars.
Each SRB at 149 feet is only two feet shorter than the Statue of Liberty. Three full-size city buses could be parked in a SRB with room to spare.
Each SRB weighs 1.2 million pounds. 1.1 million of that is propellant.
At launch, the SRBs consume 11,000 pounds of fuel per second.
When the Space Shuttle flies…
Each Space Shuttle has to operate in a temperature range that goes from 250 degrees below zero (F) in the "cold soak" of nighttime in space to nearly 3,000 degrees F on reentry.
There are approximately 27,000 tiles or blankets on each Shuttle. Surface heat dissipates so quickly on a standard Shuttle tile that an uncoated tile can be held by it edges with an ungloved hand seconds after removal from an oven, while its interior still glows red.
While flying on-orbit, the Shuttle travels at 17,500 m.p.h. or just under 5 miles per second.
During re-entry, the vehicle has to reduce its speed 98 percent through atmospheric resistance and banking turns. De-orbit burn dissipates another one percent of the Shuttle's speed. Brakes and drag chute on the runway accounts for the final one percent.
Recent Shuttle Missions
Early on the morning of February 1, 2003, after a 16-day research mission, the Space Shuttle Columbia began its re-entry into the atmosphere, heading for a homecoming at the Kennedy Space Center’s Shuttle Landing Facility. But about 15 minutes prior to Columbia's scheduled landing, Mission Control at the Johnson Space Center lost contact with the Shuttle. In east Texas, meanwhile, space travel enthusiasts were watching the orbiter break into pieces as it passed overhead. All seven Columbia crew members were killed.
The Columbia Accident Investigation Board’s preliminary accident scenario postulates that the most probable cause of the accident was a breach in the Shuttle’s left wing, leading to structural failure of that wing on re-entry. Investigators have determined that the damage to the wing possibly occurred when a piece of foam insulation broke off the External Tank about 81 seconds into launch and impacted the left wing. As of this date, the CAIB has not delivered its final report.
STS–107 was a mission designed to ensure that the NASA space research community had continuing flight opportunities during the period of Space Station construction.
The flight crew and principal investigators conducted outstanding peer-reviewed and commercial research to advance knowledge in medicine, fundamental biology, fluid physics, materials research, and combustion science. Approximately 30% of the data collect was either downlinked during the mission or recovered. The mission was comparable to the multidisciplinary Spacelab missions flown during the 1980s and 90s. In most cases, STS-107 experiments build on these highly successful results and serve as a prelude to long-duration investigations planned aboard the Station.
Endeavour launched the International Space Station P1 Truss (a support structure) on November 23, 2002. The P1 Truss is the fourth piece of the Integrated Truss Structure delivered to the Station. The P1 Truss extends the station's Mobile Transporter rail line and provides structural support for the Station's Active Thermal Control System. The new truss has mounts for cameras and lights and contains an Ultra High Frequency (UHF) antenna system.
The secondary payload was the Micro-Electromechanical System (MEMS) Based Pico Satellite Inspector that deployed two small satellites called "Picostats" (connected via a 50 ft. long tether). They are battery powered and their sole purpose is to demonstrate autonomous operation of inspection satellites and low power and mass (MEMS) system-level technology.
Atlantis delivered the S1 (S-One) Truss to the International Space Station, after its launch Oct. 2, 2002. STS-112 will set the stage for the outward expansion of the International Space Station with the delivery of the S1 (S-One) Truss. The STS-112 crew will perform three spacewalks to install, activate and outfit the S1, which will be attached to the starboard end of the S0 (S-Zero) Truss.
STS-112 will be the 15th shuttle mission to visit the space station and the 26th flight of Space Shuttle Atlantis.
The International Space Station received a new crew and a new platform for its robotic arm when Endeavour visited in June 2002. STS-111, which was the 14th Shuttle mission to visit the orbital outpost, launched June 5 and landed June 19.
STS-111 delivered the Expedition Five crew to the station and returned the Expedition Four crew to Earth. Space Shuttle Endeavour also delivered and the Mobile Base System, or MBS. The STS-111 astronauts also performed three spacewalks. Among the objectives completed during the spacewalks was permanent installation of the MBS onto the station and replacement of a wrist roll joint on the station’s robotic arm. The STS-111 crew also unloaded supplies and science experiments from the Leonardo Multi-Purpose Logistics Module, which made its third trip to the orbital outpost.
Atlantis launched the International Space Station Starboard 0 (S0) truss on April 8, 2002. The S0 truss segment was the first major element of the Station's enormous exterior framework. The S0 Truss is the center segment of 11 integrated trusses that will provide the foundation for Station subsystem hardware installation, utility distribution, power generation, heat rejection and external payload accommodations. The S0 truss acts as the junction from which external utilities are routed to the pressurized modules by means of EVA-deployed umbilical connections.
The Mobile Transporter (MT) became the first Space Station-based railroad in space during the STS-110 mission. The 885-kilogram (1,950-pound) structure will travel along the rails of the Integrated Truss Structure and, together with the Mobile Base System, will provide the work platform for the station's robotic arm.
Columbia launched the Hubble Space Telescope servicing mission components on March 1, 2002. Among the several key upgrades was the Advanced Camera for Surveys (ACS), new solar arrays, and a Near Infrared Camera and Multi-Object Spectrometer (NICMOS).
The Advanced Camera for Surveys, Hubble's new scientific instrument, gives astronomers the opportunity to discover celestial objects far beyond the reach of current instruments in a fraction of the time, unlocking more of the universe's secrets. The camera is Hubble's new workhorse, surveying far regions of the universe, searching for extra-solar planets and observing weather and other features on planets in our own solar system.
The STS-109 crew installed new solar arrays on Hubble that will significantly boost Hubble’s power. The new arrays have one-third less solar cell area, but produce at least 20 percent more power than the current set. The added power enables all the science instruments to be powered and ready to operate simultaneously, allowing for more discoveries in less time.
The STS-109 crew also installed a new cooling system for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), which had been dormant since January of 1999. Initially installed on Hubble in February 1997, NICMOS used infrared vision to explore dark, dusty regions of space with precise optical clarity. Since NICMOS operates at cold temperatures, it was encased in a container filled with solid nitrogen ice to keep the detectors cold. However, a small heat leak caused the nitrogen ice to consume more quickly than planned. The new cooling system will return the NICMOS to full operational status.
NASA is currently focusing on making the necessary repairs and upgrades to return the Shuttle fleet safely to flight. The timetable will be driven in large part by how long it takes to implement the recommendations of the CAIB. Because the Shuttle is key for staffing and supplying the Space Station, return to flight is urgent. But because safety is paramount, it will not be rushed.
The board has issued four preliminary recommendations to date: Reinforced Carbon-Carbon inspection, on-orbit imagery, Thermal Protection System on-orbit inspection and repair and improved imagery of the Shuttle system during launch and ascent. Additionally, other items are in-work that the Shuttle Program knows they will need to address before re-flight, e.g., the redesign of the foam bipod ramp on the External Tank, are already in work.
NASA has made a decision to fly the Space Shuttle Atlantis for the first two missions and both of these missions will be to the Space Station.
More information is available at http://www.spaceflight.nasa.gov