Engineers at Marshall Space Flight Center (MSFC) in Huntsville, Alabama, are working with industry partners to develop a new generation of more cost-efficient space vehicles. Lightweight fuel tanks and components under development will be the critical elements in tomorrow's reusable launch vehicles and will tremendously curb the costs of getting to space. In this photo, Tom DeLay, a materials processes engineer for MSFC, uses a new graphite epoxy technology to create lightweight cryogenic fuel lines for futuristic reusable launch vehicles. He is wrapping a water-soluble mandrel, or mold, with a graphite fabric coated with an epoxy resin. Once wrapped, the pipe will be vacuum-bagged and autoclave-cured. The disposable mold will be removed to reveal a thin-walled fuel line. In addition to being much lighter and stronger than metal, this material won't expand or contract as much in the extreme temperatures encountered by launch vehicles.

Aerovironment technicians carefully line up attachments as a fuel cell electrical system is installed on the Helios Prototype solar powered flying wing. The fuel cell system will power the aircraft at night during NASA-sponsored long-endurance demonstration flight in the summer of 2003.

CAPE CANAVERAL, Fla. – A closeup of the 7-inch quick disconnect that will be replaced on the hydrogen vent line to the Ground Umbilical Carrier Plate of space shuttle Discovery's external fuel tank. The replacement will be made on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the site during fueling caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

The checkered flag is waved as the PhoEnix aircraft crosses the finish line of the miles per gallon (MPG) flight during the 2011 Green Flight Challenge, sponsored by Google, at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Tuesday, Sept. 27, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)

CAFE Foundation Hanger Boss Mike Fenn waves the checkered flag as aircraft pass the finish line of the miles per gallon (MPG) flight during the 2011 Green Flight Challenge, sponsored by Google, at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Tuesday, Sept. 27, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)

KENNEDY SPACE CENTER, FLA. -- Workers perform post-polishing inspection on Atlantis' flow liners. Following an extensive investigation into the cause of tiny cracks inside fuel lines of the four space shuttle orbiters, a welding and polishing process is being implemented that will restore flow-liner integrity to design condition. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. The technique calls for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled on mission STS-112, an assembly flight to the International Space Station, no earlier than Sept. 28, 2002.

KENNEDY SPACE CENTER, FLA. -- Workers perform post-polishing inspection on Atlantis' flow liners. Following an extensive investigation into the cause of tiny cracks inside fuel lines of the four space shuttle orbiters, a welding and polishing process is being implemented that will restore flow-liner integrity to design condition. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. The technique calls for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled on mission STS-112, an assembly flight to the International Space Station, no earlier than Sept. 28, 2002.

KENNEDY SPACE CENTER, FLA. -- Workers perform post-polishing inspection on Atlantis' flow liners. Following an extensive investigation into the cause of tiny cracks inside fuel lines of the four space shuttle orbiters, a welding and polishing process is being implemented that will restore flow-liner integrity to design condition. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. The technique calls for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled on mission STS-112, an assembly flight to the International Space Station, no earlier than Sept. 28, 2002.

KENNEDY SPACE CENTER, FLA. - United Space Alliance technician Jerry Goudy performs arc welding on one of Atlantis' flow liners. Following an extensive investigation into the cause of tiny cracks inside fuel lines of the four space shuttle orbiters, a welding and polishing process is being implemented that will restore flow-liner integrity to design condition. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. The technique has called for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled on mission STS-112, an assembly flight to the International Space Station, no earlier than Sept. 28, 2002.

KENNEDY SPACE CENTER, FLA. - United Space Alliance technician Jerry Goudy performs arc welding on one of Atlantis' flow liners. Following an extensive investigation into the cause of tiny cracks inside fuel lines of the four space shuttle orbiters, a welding and polishing process is being implemented that will restore flow-liner integrity to design condition. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. The technique has called for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled on mission STS-112, an assembly flight to the International Space Station, no earlier than Sept. 28, 2002.

CAPE CANAVERAL, Fla. – Seen in the photo is the hydrogen vent line attached to the Ground Umbilical Carrier Plate on space shuttle Discovery's external fuel tank. The shuttle is on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the location during tanking caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

KENNEDY SPACE CENTER, FLA. -- U.S. Sen. Bill Nelson congratulates Jerry Goudy with the Flow Liner Inspection & Repair team. Nelson presented gold seal Senate certificates to the team for their work on finding the cracks in orbiter flow liners and repairing them. At left is Mike Young, behind Nelson is Tony Nesotas, at right is David Strait, who found the first fuel-line crack. Not pictured is Rick Beckwith.

ISS035-E-025557(22 April 2013) ---Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement: Cassidy accessed the Combustion Integration Rack (CIR) Combustion Chamber and removed the MDCA Chamber Insert Assembly (CIA). He then replaced the MDCA Needle 1 due to a fuel line that was damaged during previous activities when the MDCA CIA was being removed from the Combustion Chamber.

CAPE CANAVERAL, Fla. -- This diagram of a space shuttle orbiter shows the location of avionics bay 5. Space shuttle Endeavour was scheduled to launch on the STS-134 mission to the International Space Station on April 29, but that attempt was scrubbed to allow engineers to assess an issue associated with failed heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1). STS-134 will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Image credit: NASA

KENNEDY SPACE CENTER, FLA. -- U.S. Sen. Bill Nelson congratulates Rick Beckwith, with the Flow Liner Inspection & Repair team. Nelson presented gold seal Senate certificates to the team for their work on finding the cracks in orbiter flow liners and repairing them. Other team members behind Nelson are Mike Young (center) and Jerry Gouding (right). Not pictured are Tony Nesotas and David Strait. Strait first spotted the fuel-line crack; Goudy performed arc welding on one of Atlantis' flow liners.

ISS035-E-025557(22 April 2013) ---Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement: Cassidy accessed the Combustion Integration Rack (CIR) Combustion Chamber and removed the MDCA Chamber Insert Assembly (CIA). He then replaced the MDCA Needle 1 due to a fuel line that was damaged during previous activities when the MDCA CIA was being removed from the Combustion Chamber.

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, operations are under way to remove the fuel line that supplied liquid hydrogen propellant to space shuttle Atlantis’ main engine No. 2. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians remove the fuel line that supplied liquid hydrogen propellant to space shuttle Atlantis’ main engine No. 2. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, the fuel line that supplied liquid hydrogen propellant to space shuttle Atlantis’ main engine No. 2 has been disconnected from the shuttle. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, the first of three fuel lines that supplied liquid hydrogen propellant to space shuttle Atlantis’ main engines is disconnected from the shuttle. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians work with other technicians inside space shuttle Atlantis’ aft compartment, out of view, to remove the fuel line that supplied liquid hydrogen propellant to Atlantis’ main engine No. 2. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, the camera catches a glimpse of the complex infrastructure in space shuttle Atlantis’ aft compartment as operations get under way to remove one of three fuel lines that supplied liquid hydrogen propellant to Atlantis’ main engines. The liquid hydrogen lines will be placed in storage to preserve the option to reuse them on NASA’s Space Launch System heavy-lift vehicle, under development. The work is part of the Space Shuttle Program’s transition and retirement processing of shuttle Atlantis. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

KENNEDY SPACE CENTER, FLA. - U.S. Sen. Bill Nelson (right) honors the Flow Liner Inspection & Repair team for their work on repairing the flow liners on the orbiters. The team (background) comprises (left to right) Rick Beckwith, STR engineer; Mike Young, MPS engineer; Jerry Goudy, welder; Tony Nesotas, OFP-2 aft technician; and David Strait, OPF-2 orbiter inspector. Strait first spotted the fuel-line crack; Goudy performed arc welding on one of Atlantis' flow liners. Nelson presented gold seal Senate certificates to the team.

KENNEDY SPACE CENTER, FLA. -- U.S. Sen. Bill Nelson, left, talks to the Flow Liner Inspection & Repair team members, who are with United Space Alliance (USA). Nelson presented a gold seal Senate certificate to the team for their part in finding the cracks in orbiter flow liners and repairing them. On the right is David Strait, orbiter inspector, who first spotted the fuel-line crack. Second from the right is Jerry Goudy, welder, who performed arc welding on one of Atlantis' flow liners. Between Goudy and Nelson is Rick Beckwith, structural engineer.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., a worker attaches a high pressure line on the THEMIS spacecraft in preparation for fueling, which is scheduled for Jan. 3-5. THEMIS consists of five identical probes, the largest number of scientific satellites ever launched into orbit aboard a single rocket. This unique constellation of satellites will resolve the tantalizing mystery of what causes the spectacular sudden brightening of the aurora borealis and aurora australis - the fiery skies over the Earth's northern and southern polar regions. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., a worker attaches a high pressure line on the THEMIS spacecraft in preparation for fueling, which is scheduled for Jan. 3-5. THEMIS consists of five identical probes, the largest number of scientific satellites ever launched into orbit aboard a single rocket. This unique constellation of satellites will resolve the tantalizing mystery of what causes the spectacular sudden brightening of the aurora borealis and aurora australis - the fiery skies over the Earth's northern and southern polar regions. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., a worker attaches a high pressure line on the THEMIS spacecraft in preparation for fueling, which is scheduled for Jan. 3-5. THEMIS consists of five identical probes, the largest number of scientific satellites ever launched into orbit aboard a single rocket. This unique constellation of satellites will resolve the tantalizing mystery of what causes the spectacular sudden brightening of the aurora borealis and aurora australis - the fiery skies over the Earth's northern and southern polar regions. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

CAPE CANAVERAL, Fla. -- This diagram of a space shuttle orbiter's avionics bay 5 shows the location of aft load control assembly-2 (ALCA-2) inside the bay. Space shuttle Endeavour was scheduled to launch on the STS-134 mission to the International Space Station on April 29, but that attempt was scrubbed to allow engineers to assess an issue associated with failed heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1). STS-134 will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Image credit: NASA

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

STS045-71-001 (24 March 1992) --- This 70mm photograph of the external fuel tank (ET) for STS-45 was photographed 4 1/2 minutes after having been jettisoned from Space Shuttle Atlantis. The excellent view of the starboard side of the ET shows both top and bottom attach points to the two solid rocket boosters (SRB). NASA engineers studying the STS-45 onboard photography deem the visible burn scars, caused by the SRBs, to be normal. The long thin pipe visible is the liquid oxygen line. At the bottom end of the large tank, both the liquid oxygen (nearest camera) and liquid hydrogen orbiter-to-ET attach hardware can be seen.

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

KENNEDY SPACE CENTER, FLA. -- U.S. Sen. Bill Nelson (front) presents gold seal Senate certificates to the Flow Liner Inspection & Repair team for their work on repairing the flow liners on the orbiters. The team (background) comprises (left to right) Rick Beckwith, STR engineer; Mike Young, MPS engineer; Jerry Goudy, welder; Tony Nesotas, OFP-2 aft technician; and David Strait, OPF-2 orbiter inspector. Strait first spotted the fuel-line crack; Goudy performed arc welding on one of Atlantis' flow liners.

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

This STS-29 mission onboard photo depicts the External Tank (ET) falling toward the ocean after separation from the Shuttle orbiter Discovery. The giant cylinder, higher than a 15-story building, with a length of 154-feet (47-meters) and a diameter of 27,5-feet (8.4-meters), is the largest single piece of the Space Shuttle. During launch, the ET also acts as a backbone for the orbiter and solid rocket boosters. In separate, internal pressurized tank sections, the ET holds the liquid hydrogen fuel and liquid oxygen oxidizer for the Shuttle's three main engines. During launch, the ET feeds the fuel under pressure through 17-inch (43.2-centimeter) ducts which branch off into smaller lines that feed directly into the main engines. Some 64,000 gallons (242,260 liters) of fuel are consumed by the main engines each minute. Machined from aluminum alloys, the Space Shuttle's ET is the only part of the launch vehicle that currently is not reused. After its 526,000 gallons (1,991,071 liters) of propellants are consumed during the first 8.5 minutes of flight, it is jettisoned from the orbiter and breaks up in the upper atmosphere, its pieces falling into remote ocean waters. The Marshall Space Flight Center was responsible for developing the ET.

This is a cutaway illustration of the Space Shuttle external tank (ET) with callouts. The giant cylinder, higher than a 15-story building, with a length of 154-feet (47-meters) and a diameter of 27.5-feet (8.4-meters), is the largest single piece of the Space Shuttle. During launch, the ET also acts as a backbone for the orbiter and solid rocket boosters. Separate pressurized tank sections within the external tank hold the liquid hydrogen fuel and liquid oxygen oxidizer for the Shuttle's three main engines. During launch, the ET feeds the fuel under pressure through 17-inch (43.2-centimeter) ducts that branch off into smaller lines that feed directly into the main engines. The main engines consume 64,000 gallons (242,260 liters) of fuel each minute. Machined from aluminum alloys, the Space Shuttle's external tank is currently the only part of the launch vehicle that is not reused. After its 526,000-gallons (1,991,071 liters) of propellants are consumed during the first 8.5-minutes of flight, it is jettisoned from the orbiter and breaks up in the upper atmosphere, its pieces falling into remote ocean waters. The Marshall Space Flight Center was responsible for developing the ET.

This photograph was taken during the final assembly phase of the Space Shuttle light weight external tanks (LWT) 5, 6, and 7 at the Michoud Assembly Facility in New Orleans, Louisiana. The giant cylinder, higher than a 15-story building, with a length of 154-feet (47-meters) and a diameter of 27.5-feet (8.4-meters), is the largest single piece of the Space Shuttle. During launch, the external tank (ET) acts as a backbone for the orbiter and solid rocket boosters. In separate, internal pressurized tank sections, the ET holds the liquid hydrogen fuel and liquid oxygen oxidizer for the Shuttle's three main engines. During launch, the ET feeds the fuel under pressure through 17-inch (43.2-centimeter) ducts which branch off into smaller lines that feed directly into the main engines. Some 64,000 gallons (242,260 liters) of fuel are consumed by the main engines each minute. Machined from aluminum alloys, the Space Shuttle's ET is the only part of the launch vehicle that currently is not reused. After its 526,000 gallons (1,991,071 liters) of propellants are consumed during the first 8.5 minutes of flight, it is jettisoned from the orbiter and breaks up in the upper atmosphere, its pieces falling into remote ocean waters. The Marshall Space Flight Center was responsible for developing the ET

A Fairchild C-82 Packet is purposely destroyed by researchers at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. In response to an escalating number of transport aircraft crashes in the mid-1940s, the NACA researchers undertook a decade-long investigation into a number of issues surrounding low-altitude aircraft crashes. The tests were conducted at the Ravenna Arsenal, approximately 60 miles south of the Lewis laboratory in Cleveland, Ohio. The aircraft were excess military transports from World War II. The aircraft was guided down the runway at speeds of 80 to 105 miles per hour. It came into contact with poles which tore open the 1500-gallon fuel tanks in the wings before reaching the barriers at the end of the runway. Fuel poured from the tanks and supply lines, resulting in the spread of both liquid fuel and a large cloud of spray. Solomon Weiss developed a method of dying the fuel red to improve its visibility during the crashes. This red fuel cloud trailed slightly behind the skidding aircraft, then rushed forward when the aircraft stopped. The nine-crash initial phase of testing used Lockheed C-56 Lodestar and C-82 transport aircraft to identify potential ignition sources and analyze the spread of flammable materials. The researchers were able to identify different classes of ignition sources, fuel disbursement patterns, the time when a particular ignition source might appear, rate of the fire spread, cabin survival times, and deceleration rates.

KENNEDY SPACE CENTER, FLA. -- Space Shuttle Atlantis, mounted on a mobile launch platform, finally rests on the hard stand of Launch Pad 39A after an early morning rollout. This is the second rollout for the shuttle. Seen on either side of the main engine exhaust hole on the launcher platform are the tail service masts. Their function is to provide umbilical connections for liquid oxygen and liquid hydrogen lines to fuel the external tank from storage tanks adjacent to the launch pad. Other umbilical lines carry helium and nitrogen, as well as ground electrical power and connections for vehicle data and communications. First motion out of the Vehicle Assembly Building was at 5:02 a.m. EDT. In late February, while Atlantis was on the launch pad, Atlantis' external tank received hail damage during a severe thunderstorm that passed through the Kennedy Space Center Launch Complex 39 area. The hail caused visible divots in the giant tank's foam insulation, as well as minor surface damage to about 26 heat shield tiles on the shuttle's left wing. The shuttle was returned to the VAB for repairs. The launch of Space Shuttle Atlantis on mission STS-117 is now targeted for June 8. A flight readiness review will be held on May 30 and 31. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center’s in Florida, a technician conducts terahertz scans of five ice frost ramps on the external fuel tank, designated ET-133, for space shuttle Atlantis’ STS-129 mission. The ice frost ramps are made from foam insulation and cover brackets that hold pressurization lines on the outside of the external tank. Terahertz scans are wave frequency analysis in the infrared band that can see through the foam insulation to help look for any voids or pockets where the foam is not bonded to the metal primer. The ramps being scanned were on the top part of the tank in the same area where foam came off during the last two shuttle launches. The data will be used to help assess whether foam on ET-132, the fuel tank attached to shuttle Discovery at Kennedy’s Launch Pad 39A, is fit for its flight on the STS-128 mission to the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center’s in Florida, technicians set up equipment that will be used to conduct terahertz scans of five ice frost ramps on the external fuel tank, designated ET-133, for space shuttle Atlantis’ STS-129 mission. The ice frost ramps are made from foam insulation and cover brackets that hold pressurization lines on the outside of the external tank. Terahertz scans are wave frequency analysis in the infrared band that can see through the foam insulation to help look for any voids or pockets where the foam is not bonded to the metal primer. The ramps being scanned were on the top part of the tank in the same area where foam came off during the last two shuttle launches. The data will be used to help assess whether foam on ET-132, the fuel tank attached to shuttle Discovery at Kennedy’s Launch Pad 39A, is fit for its flight on the STS-128 mission to the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center’s in Florida, a technician prepares to conduct terahertz scans of five ice frost ramps on the external fuel tank, designated ET-133, for space shuttle Atlantis’ STS-129 mission. The ice frost ramps are made from foam insulation and cover brackets that hold pressurization lines on the outside of the external tank. Terahertz scans are wave frequency analysis in the infrared band that can see through the foam insulation to help look for any voids or pockets where the foam is not bonded to the metal primer. The ramps being scanned were on the top part of the tank in the same area where foam came off during the last two shuttle launches. The data will be used to help assess whether foam on ET-132, the fuel tank attached to shuttle Discovery at Kennedy’s Launch Pad 39A, is fit for its flight on the STS-128 mission to the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center’s in Florida, a technician conducts terahertz scans of five ice frost ramps on the external fuel tank, designated ET-133, for space shuttle Atlantis’ STS-129 mission. The ice frost ramps are made from foam insulation and cover brackets that hold pressurization lines on the outside of the external tank. Terahertz scans are wave frequency analysis in the infrared band that can see through the foam insulation to help look for any voids or pockets where the foam is not bonded to the metal primer. The ramps being scanned were on the top part of the tank in the same area where foam came off during the last two shuttle launches. The data will be used to help assess whether foam on ET-132, the fuel tank attached to shuttle Discovery at Kennedy’s Launch Pad 39A, is fit for its flight on the STS-128 mission to the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center’s in Florida, a technician sets up equipment to support terahertz scans of five ice frost ramps on the external fuel tank, designated ET-133, for space shuttle Atlantis’ STS-129 mission. The ice frost ramps are made from foam insulation and cover brackets that hold pressurization lines on the outside of the external tank. Terahertz scans are wave frequency analysis in the infrared band that can see through the foam insulation to help look for any voids or pockets where the foam is not bonded to the metal primer. The ramps being scanned were on the top part of the tank in the same area where foam came off during the last two shuttle launches. The data will be used to help assess whether foam on ET-132, the fuel tank attached to shuttle Discovery at Kennedy’s Launch Pad 39A, is fit for its flight on the STS-128 mission to the International Space Station. Photo credit: NASA/Kim Shiflett

There’s more than one way to study the impact of biofuels. For NASA scientists, it means trailing an aircraft from as little as 300 feet behind while flying 34,000 feet in the air. Earlier this year, a NASA-led team conducted a series of carefully choreographed flights over California in order to sniff out how aircraft emissions differ when using petroleum fuels or biofuels. Early results from the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS II) experiment confirm that blended biofuel is the cleaner-burning fuel. &quot;Our findings show we definitely see a 50 percent reduction in soot emissions from the DC-8 when it burns the blended fuel as opposed to jet fuel alone,&quot; said Bruce Anderson, ACCESS principal investigator from NASA's Langley Research Center. The DC-8 is a NASA science workhorse: a flying laboratory equipped to collect—or, in this case, produce—data for basic Earth science research. During the ACESS experiment, scientists took advantage of the aircraft's segregated fuel tank. On the fly, the pilot switched the fuel type sent to each of the four engines. The engines burned either jet fuel, or a 50-50 blend of jet fuel and a renewable alternative produced from camelina plant oil. With each change of fuel, three other instrumented aircraft took turns lining up in the DC-8's wake and flying anywhere from 90 meters (300 feet) to more than 30 kilometers (20 miles) behind to catch a sniff. Richard Moore, a post-doctoral fellow at NASA Langley, took this photograph with a DSLR camera on May 7, 2014, during an ACCESS II test flight over Edwards Air Force Base in California. The photo was taken from Langley's HU-25C Guardian jet as it descended toward NASA's Armstrong Flight Research Center after a successful three-hour sampling flight behind the DC-8. The aircraft trailing the DC-8 in the photo was a Falcon 20-E5 jet owned by the German Aerospace Center. The flight on May 7 was just the first in a series of flights that lasted throughout the month. After the campaign, researchers continued to examine the data to determine whether a reduction in soot emissions translates to a reduction in contrail formation, and how that might affect climate. Read more: <a href="http://1.usa.gov/1wBfaKq" rel="nofollow">1.usa.gov/1wBfaKq</a> <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b> <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. <b>Follow us on <a href="http://twitter.com/NASAGoddardPix" rel="nofollow">Twitter</a></b> <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b> <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>

CAPE CANAVERAL, Fla. --The Load Control Assembly-2 (LCA-2) is outside at NASA Kennedy Space Center's Launch Pad 39A after it was removed from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, technicians inside space shuttle Endeavour's aft section test the Load Control Assembly-2 (LCA-2). Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations are under way to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, a worker inside space shuttle Endeavour's aft section removes a cover to provide access for the removal and replacement of the Load Control Assembly-2 (LCA-2). Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

On March 11, Boeing mated the upper and lower domes of its CST-100 Starliner spacecraft slated to fly in the company’s Orbital Flight Test (OFT). The mate was completed at Boeing’s Commercial Crew and Cargo Processing Facility at NASA’s Kennedy Space Center in Florida. Starliner uses an innovative weldless design where the main structure is made of two domes, each spin-formed and machined from a solid piece of aerospace-grade aluminum. The two domes then undergo outfitting with avionics, cooling systems, wire harnesses, fuel and life support lines, and other critical systems before being mated together. This is one of the last major milestones ahead of final processing and closeouts for flight. OFT is Boeing’s uncrewed flight test of Starliner and part of NASA’s Commercial Crew Program, which will return human spaceflight launches into low-Earth orbit from U.S. soil.

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, a technician makes his way across a platform in space shuttle Endeavour's aft section as work begins to remove and replace the aft load control assembly-2 (ALCA-2). Located in the orbiter's aft avionics bay 5, the assembly is believed to have caused heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, the Load Control Assembly-2 (LCA-2) has been replaced inside of space shuttle Endeavour. Located in Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission and has been replaced. Systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

S71-16823 (January 1971) --- A line drawing illustrating a cutaway view of the Apollo 14 Command and Service Modules, showing the engineering changes in the CSM which were recommended by the Apollo 13 Review Board. (The Apollo 13 abort was caused by a short circuit and wiring overheating in one of the SM cryogenic oxygen tanks.) The major changes to the Apollo 14 CSM include adding a third cryogenic oxygen tank installed in a heretofore empty bay (in sector one) of the SM, addition of an auxiliary battery in the SM as a backup in case of fuel cell failure, and removal of destratification fans in the cryogenic oxygen tanks and removal of thermostat switches from the oxygen tank heater circuits. Provision for stowage of an emergency five-gallon supply of drinking water has been added to the CM.

CAPE CANAVERAL, Fla. -- At the NASA Shuttle Logistics Depot in Cape Canaveral, Florida, the Load Control Assembly-2 (LCA-2) is uncovered for testing. Located in space shuttle Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The LCA-2 will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, workers inside space shuttle Endeavour's aft section help prepare for the upcoming removal and replacement of the aft load control assembly-2 (ALCA-2). Located in the orbiter's aft avionics bay 5, the assembly is believed to have caused heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations are under way to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, a worker inside space shuttle Endeavour's aft section removed a cover to provide access for the removal and replacement of the Load Control Assembly-2 (LCA-2). Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

KENNEDY SPACE CENTER, FLA. -- At the KSC Press Site, Jerry Goudy, a technician with United Space Alliance, poses with his helmet and a sample flow liner used in an orbiter. Cracks were found in several flow liners recently; Goudy was responsible for welding the cracks in Atlantis. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. A welding and polishing process is being implemented that will restore flow-liner integrity to design condition. The technique has called for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled to fly on mission STS-112.

CAPE CANAVERAL, Fla. -- At the NASA Shuttle Logistics Depot in Cape Canaveral, Florida, technicians remove the cover on the Load Control Assembly-2 (LCA-2) to begin the testing process. Located in space shuttle Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The LCA-2 will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, the Load Control Assembly-2 (LCA-2) is removed from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, technicians begin to remove the Load Control Assembly-2 (LCA-2) from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A work station, a replacement Load Control Assembly-2 (LCA-2) is being prepared for installation into Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Control Center, teams monitor the testing of the Load Control Assembly-2 (LCA-2) located in space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker begins to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. – Seen in the photo is the 7-inch quick disconnect that will be repaired on the hydrogen vent line to the Ground Umbilical Carrier Plate on space shuttle Endeavour's external fuel tank on Launch Pad 39A at NASA's Kennedy Space Center in Florida. Teams are removing the hardware to change out seals in the internal connection points. A leak of hydrogen at the location during tanking June 12 for the STS-127 mission caused the mission to be scrubbed at 12:26 a.m. June 13. The GUCP is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Endeavour is scheduled to launch on its STS-127 mission on June 17 at 5:40 a.m. EDT. Photo credit: NASA/Tim Jacobs

NASA engineers successfully tested a Russian-built rocket engine on November 4, 1998 at the Marshall Space Flight Center (MSFC) Advanced Engine Test Facility, which had been used for testing the Saturn V F-1 engines and Space Shuttle Main engines. The MSFC was under a Space Act Agreement with Lockheed Martin Astronautics of Denver to provide a series of test firings of the Atlas III propulsion system configured with the Russian-designed RD-180 engine. The tests were designed to measure the performance of the Atlas III propulsion system, which included avionics and propellant tanks and lines, and how these components interacted with the RD-180 engine. The RD-180 is powered by kerosene and liquid oxygen, the same fuel mix used in Saturn rockets. The RD-180, the most powerful rocket engine tested at the MSFC since Saturn rocket tests in the 1960s, generated 860,000 pounds of thrust.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- At the NASA Shuttle Logistics Depot in Cape Canaveral, Florida, technicians remove the cover on the Load Control Assembly-2 (LCA-2) to begin the testing process. Located in space shuttle Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The LCA-2 will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, a worker inside space shuttle Endeavour's aft section removes a cover to provide access for the removal and replacement of the Load Control Assembly-2 (LCA-2). Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, the Load Control Assembly-2 (LCA-2) is removed from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

KENNEDY SPACE CENTER, FLA. -- At the KSC Press Site, Jerry Goudy (background), a technician with United Space Alliance, explains to the media the welding used to fix the cracks found recently in orbiter flow liners. Goudy was responsible for welding the cracks in Atlantis. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. A welding and polishing process is being implemented that will restore flow-liner integrity to design condition. The technique has called for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled to fly on mission STS-112.

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, a worker inside space shuttle Endeavour's aft section is testing the Load Control Assembly-2 (LCA-2) for replacement. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

KENNEDY SPACE CENTER, FLA. -- At the KSC Press Site, Jerry Goudy (left), a technician with United Space Alliance, shows the media an orbiter flow liner similar to the ones in which cracks were found recently. Goudy was responsible for welding the cracks in Atlantis. These liners are inside the space shuttle Main Propulsion System fuel lines to preclude liquid hydrogen and oxygen turbulent flow into the engines during launch and climb to orbit. A welding and polishing process is being implemented that will restore flow-liner integrity to design condition. The technique has called for welds of three very small cracks on Atlantis and two on Endeavour. Additionally, the microscopic rough edges of the liner holes are being smoothed by polishing to reduce the chance of more cracks developing in the future. Atlantis is scheduled to fly on mission STS-112.

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations are under way to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, technicians are begin to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, technicians work to remove the Load Control Assembly-2 (LCA-2) from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Control Center, teams monitor the testing of the Load Control Assembly-2 (LCA-2) located in space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. -- At the NASA Shuttle Logistics Depot in Cape Canaveral, Florida, technicians carefully remove the Load Control Assembly-2 (LCA-2) from a cart for testing. Located in space shuttle Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The LCA-2 will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, the Load Control Assembly-2 (LCA-2) has been replaced inside of space shuttle Endeavour. Located in Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission and has been replaced. Systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

CAPE CANAVERAL, Fla. -- At the NASA Shuttle Logistics Depot in Cape Canaveral, Florida, the Load Control Assembly-2 (LCA-2) is uncovered for testing. Located in space shuttle Endeavour's aft avionics bay 5, the LCA-2, which distributes power to nine shuttle systems, is believed to have caused fuel line heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The LCA-2 will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA Kennedy Space Center's Launch Pad 39A, the Load Control Assembly-2 (LCA-2) is removed from inside space shuttle Endeavour's aft section. Located in the orbiter's aft avionics bay 5, the LCA-2 assembly, which feeds power to the fuel line heaters, is believed to have caused the heaters for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. The assembly will be replaced and systems will be retested before the launch is rescheduled. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations are under way to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations are under way to reattach the vent line to the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Ben Smegelsky

CAPE CANAVERAL, Fla. -- Barely visible inside space shuttle Endeavour's aft section, a technician at NASA Kennedy Space Center's Launch Pad 39A helps prepare for the upcoming removal and replacement of the aft load control assembly-2 (ALCA-2). Located in the orbiter's aft avionics bay 5, the assembly is believed to have caused heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett