The STS-6 flight, the first space voyage of Challenger, is symbolized by the hexagonal shape of its crew emblem. The overall color theme of the patch is a patriotic red, white and blue. It has a border of royal blue, which surrounds an inner band of white. This inner band is bordered on the interior by a thin red line. This band lists, in royal blue to match the border, the surnames of Challenger’s four crew members – astronauts Paul J. Weitz, Karol J. Bobko, F. Story Musgrave, and Donald H. Peterson – along with the mission’s sequence numeral and the name of the spacecraft in the inner line’s red color.
The center area of the patch is dominated by a spacescape, which depicts the orbiter flying in the foreground as it creates an orbital path from behind the Earth. The planet is depicted as a large, light-blue sphere, rimmed with a slightly darker blue. The orbiter is seen in a side – and slightly frontal – view with the payload bay doors open. The Tracking and Data Relay Satellite, combined with the Inertial Upper Stage, is depicted during its deployment from the Challenger’s cargo bay. It trails a white streamer behind the far side of the globe, just as Challenger trails a red one. Both the orbiter and the TDRS are shown in shades of white, with light blue shading and black detail. The IUS has got a band of red on its exterior.
Slightly above and behind Challenger are shining white stars which form the constellation Virgo. These six stars against a background of deep navy blue represent the mission sequence number – whereby the five stars to the right of the vertical tail symbolize Columbia’s five trips into space, the lone star to the left the first use of the newest member of the Space Shuttle fleet. Virgo itself is also symbolic of the maiden flight of Challenger.
The spacecraft Challenger was the “Early Bird” of America’s Space Transportation System’s Earth-orbiting fleet. Structural fabrication of Challenger had commenced on January 6, 1975, about a year earlier than the origin of Columbia. In several transitional periods Challenger went from structural assembly to becoming the Structural Test Article (STA-099), then back into manufacturing modification period for renovation and uprating to “flight worthy” status to final assembly.
Rockwell’s original $2.6 billion contract had authorized the building of a pair of static test articles (MPTA-098 and STA-099) and two initial flight test vehicles (OV-101 and OV-102). The 1978 decision not to modify Enterprise from her ALT configuration would leave only one space-rated orbiter. This vehicle, Columbia, was rolled out of the Palmdale plant on March 8, 1979.
While Enterprise and MPTA-098 were undergoing tests, Lockheed-California in Palmdale was busy trying to verify the structural integrity of STA-099. On February 4, 1978, Rockwell had delivered the nearly-complete airframe to the Lockheed-California Company located across the runway at Plant 42. Twelve months of testing would take place in a 43-ton steel rig built especially for the Space Shuttle test program.
The test rig contained 256 hydraulic jacks, distributed over 836 load application points, which simulated various stress levels under control of a computer. These stress levels duplicated the launch, ascent, on-orbit, reentry and landing phases of flight. Three 1,000,000 pound-force hydraulic cylinders were used to simulate the thrust from the Space Shuttle Main Engines. Heating and cooling simulations were conducted along with the stress tests.
In the meantime, on January 5, 1979, NASA awarded Rockwell a supplemental contract to modify STA-099 into a space-rated orbiter (OV-099), and followed this on January 29, 1979, with an order to construct two additional vehicles (OV-103 and OV-104). This $1.9 billion contract also covered modifying OV-102 following the orbital flight test series (STS-1 thru STS-4).
On February 2, 1979, the Structural Test Article officially was renamed Challenger. Like Columbia (and, indeed, the subsequent vehicles), Challenger was named for a seafaring vessel that had made a prolonged cruise from December 1872 until May 1876, gathering the equivalent of 50 volumes of information about the Atlantic and Pacific Oceans. Later, the name’s proud heritage continued when the Apollo 17 crew chose it for their lunar module in December 1972.
Testing was completed successfully and Challenger was returned to Rockwell on November 7, 1979, for conversion into OV-099. This conversion, while easier than it would have been to convert Enterprise, still involved a major disassembly of the vehicle. Within a month of arriving back from Lockheed, the payload bay doors, elevons and body flap had been removed so they could be returned to the original vendors for modifications. By January 18, 1980, the vertical stabilizer had been removed and shipped back to Fairchild-Republic in New York for rework.
Challenger had been built with a simulated crew module (which had arrived at Palmdale on January 28, 1977), and the forward fuselage halves had to be separated to gain access to the crew module. This had occurred on February 1981, and the upper forward fuselage was subsequently sent to Downey for rework. The construction of a space-worthy crew module design had already started with long-lead fabrication on January 2, 1979. This had been followed by the start of crew module assembly on June 21, 1979, followed by installation of initial systems on November 3, 1980. On July 14, 1981, the crew module arrived at Palmdale for integration into the vehicle structure. The lower fuselage was modified in Palmdale. The entire aft fuselage was removed and sent to Downey for modifications, returning to Palmdale on July 21, 1981.
On October 15, 1976, the mid-fuselage for STA-099 had arrived at Palmdale for integration with the rest of the vehicle’s components. Following the structural test program, preparations for the modifications to the mid-fuselage were begun on January 28, 1980. On May 26, 1977, the aft payload bay doors for STA-099 had arrived at Palmdale, followed by the forward doors on July 22. On December 7, 1979, after completion of the STA program, the doors were demated from Challenger for rework to orbital certification. By January 25, 1980, the doors had arrived at Rockwell, Tulsa, for rework operations, and were delivered for configuration on Challenger on July 10, 1981.
The final assembly of the vertical tail had begun on October 1, 1976, the structure being delivered on dock at Palmdale on April 6, 1977. It had been mated to STA-099 on September 30, 1977, and, after the structural test program, was demated and delivered back to Fairchild, New York, on January 18, 1980, for rework. It was on dock at Palmdale again on March 26, 1981, for mating to Challenger.
The body flap for Challenger had arrived on dock at Palmdale on May 31, 1977, and after the STA program was demated by December 14, 1979, for rework, returning to Downey on January 25, 1980. On September 1, 1980, modifications to the body flap were begun. The modifications were completed by July 17 and the unit was placed on dock at Palmdale on July 24, 1981, for final installation activities.
The final assembly of the original STA-099 wings had begun at the prime contractor on October 1, 1976, and the units had arrived on dock at Palmdale on March 16, 1977. Following the completion of the STA program, the elevons were demated on December 21, 1979 and returned to the prime contractor for rework on February 1, 1980. Three days later the preparations for the wing modifications were started, this part of the program being completed by November 21 of the same year. By March 30, 1981, the rework on the elevons had been completed at Palmdale, and these units were installed on Challenger’s wings.
Additionally the wings were modified to incorporate lessons learned from the static testing. Part of the new loads data base analysis also allowed Rockwell to relax the requirements for the wing design on OV-103 and OV-104 in order to achieve a slight weight reduction. Challenger would end up some 2,486 pounds lighter than Columbia, in spite of having additional operational equipment installed, including two heads-up displays in the cockpit.
On November 7, 1977, the Forward Reaction Control System (FRCS) for STA-099 had arrived on dock at Palmdale, and was demated by February 8, 1980, following completion of the STA program. By March 21, 1980, the forward RCS had arrived at Downey for rework to flight standard. On February 2, 1981, installation of the system components started, the package finally arriving at Palmdale on January 31, 1982, for installation in Challenger.
The first set of OMS pods for Challenger arrived early in 1982 at Palmdale for installation of the TPS. The right-hand pod was delivered on February 15, and the left-hand pod on March 3. Following this activity the pods were transported to KSC on September 3, 1982, for installation on Challenger for its first mission.
By October 23, 1981, the airframe had been modified to flight standard, and on October 26 the initial series of powered subsystems tests was started. An unpowered subsystems test was begun on November 2, and by January 29, 1982, the initial subsystems tests series had been completed. On April 16 the Challenger’s subsystems were cleared for operational use, and on April 30, 1982, the final acceptance test was completed at the Palmdale plant. In June 1982 Challenger received her final certifications before delivery. On June 4 the post-checkout operations were successfully completed, as was the configuration inspection 17 days later.
Challenger had been built with a simulated crew module (which had arrived at Palmdale on January 28, 1977), and the forward fuselage halves had to be separated to gain access to the crew module. This had occurred on February 1981, and the upper forward fuselage was subsequently sent to Downey for rework. The construction of a space-worthy crew module design had already started with long-lead fabrication on January 2, 1979. This had been followed by the start of crew module assembly on June 21, 1979, followed by installation of initial systems on November 3, 1980. On July 14, 1981, the crew module arrived at Palmdale for integration into the vehicle structure. The lower fuselage was modified in Palmdale. The entire aft fuselage was removed and sent to Downey for modifications, returning to Palmdale on July 21, 1981.
On October 15, 1976, the mid-fuselage for STA-099 had arrived at Palmdale for integration with the rest of the vehicle’s components. Following the structural test program, preparations for the modifications to the mid-fuselage were begun on January 28, 1980. On May 26, 1977, the aft payload bay doors for STA-099 had arrived at Palmdale, followed by the forward doors on July 22. On December 7, 1979, after completion of the STA program, the doors were demated from Challenger for rework to orbital certification. By January 25, 1980, the doors had arrived at Rockwell, Tulsa, for rework operations, and were delivered for configuration on Challenger on July 10, 1981.
The final assembly of the vertical tail had begun on October 1, 1976, the structure being delivered on dock at Palmdale on April 6, 1977. It had been mated to STA-099 on September 30, 1977, and, after the structural test program, was demated and delivered back to Fairchild, New York, on January 18, 1980, for rework. It was on dock at Palmdale again on March 26, 1981, for mating to Challenger.
The body flap for Challenger had arrived on dock at Palmdale on May 31, 1977, and after the STA program was demated by December 14, 1979, for rework, returning to Downey on January 25, 1980. On September 1, 1980, modifications to the body flap were begun. The modifications were completed by July 17 and the unit was placed on dock at Palmdale on July 24, 1981, for final installation activities.
The final assembly of the original STA-099 wings had begun at the prime contractor on October 1, 1976, and the units had arrived on dock at Palmdale on March 16, 1977. Following the completion of the STA program, the elevons were demated on December 21, 1979 and returned to the prime contractor for rework on February 1, 1980. Three days later the preparations for the wing modifications were started, this part of the program being completed by November 21 of the same year. By March 30, 1981, the rework on the elevons had been completed at Palmdale, and these units were installed on Challenger’s wings.
Additionally the wings were modified to incorporate lessons learned from the static testing. Part of the new loads data base analysis also allowed Rockwell to relax the requirements for the wing design on OV-103 and OV-104 in order to achieve a slight weight reduction. Challenger would end up some 2,486 pounds lighter than Columbia, in spite of having additional operational equipment installed, including two heads-up displays in the cockpit.
On November 7, 1977, the Forward Reaction Control System (FRCS) for STA-099 had arrived on dock at Palmdale, and was demated by February 8, 1980, following completion of the STA program. By March 21, 1980, the forward RCS had arrived at Downey for rework to flight standard. On February 2, 1981, installation of the system components started, the package finally arriving at Palmdale on January 31, 1982, for installation in Challenger.
The first set of OMS pods for Challenger arrived early in 1982 at Palmdale for installation of the TPS. The right-hand pod was delivered on February 15, and the left-hand pod on March 3. Following this activity the pods were transported to KSC on September 3, 1982, for installation on Challenger for its first mission.
By October 23, 1981, the airframe had been modified to flight standard, and on October 26 the initial series of powered subsystems tests was started. An unpowered subsystems test was begun on November 2, and by January 29, 1982, the initial subsystems tests series had been completed. On April 16 the Challenger’s subsystems were cleared for operational use, and on April 30, 1982, the final acceptance test was completed at the Palmdale plant. In June 1982 Challenger received her final certifications before delivery. On June 4 the post-checkout operations were successfully completed, as was the configuration inspection 17 days later.
On June 30, 1982, the vehicle was officially rolled out of the Palmdale facility, completing more than 7 1/2 years work, so bringing it up to operational standard as the second flight vehicle. On July 1, 1982, as her sister ship Columbia was orbiting the Earth during the fourth flight day of the fourth shuttle mission, Challenger was transported by road in a 38-mile journey from the Palmdale plant to Edwards Air Force Base for attachment to the Shuttle Carrier Aircraft for its journey to KSC.
Challenger was the first orbiter delivered with a name on the upper right wing and the “USA” and American flag on the left. The new stylized NASA logo and the name Challenger appeared on the right wing. The name of the vehicle was also positioned beneath the cockpit windows on the side of the forward fuselage, which remained visible with payload bay doors open for on-orbit identification.
Shortly after Columbia STS-4 landed at Edwards AFB, completing the fourth flight of the program and its OFT series, Challenger was sent on its way to KSC by President Reagan, the vehicle taking to the air for the first time on the USA’s 206th birthday, July 4, 1982. Literally millions first saw Challenger when, atop the 747 Shuttle Carrier Aircraft, the orbiter’s right wing was dipped during a nationally televised low-pass salute to President and Mrs. Reagan at Edwards Air Force Base.
The SCA flew to Florida in two stages, taking the orbiter to Ellington Field, Texas, for an overnight stop and finally, on July 5, from Ellington Field to Kennedy Space Center, Florida. Following demate from the SCA Challenger was moved to the OPF to begin final preparations for its first flight on STS-6 early in 1983.
Challenger was the first orbiter delivered with a name on the upper right wing and the “USA” and American flag on the left. The new stylized NASA logo and the name Challenger appeared on the right wing. The name of the vehicle was also positioned beneath the cockpit windows on the side of the forward fuselage, which remained visible with payload bay doors open for on-orbit identification.
Shortly after Columbia STS-4 landed at Edwards AFB, completing the fourth flight of the program and its OFT series, Challenger was sent on its way to KSC by President Reagan, the vehicle taking to the air for the first time on the USA’s 206th birthday, July 4, 1982. Literally millions first saw Challenger when, atop the 747 Shuttle Carrier Aircraft, the orbiter’s right wing was dipped during a nationally televised low-pass salute to President and Mrs. Reagan at Edwards Air Force Base.
The SCA flew to Florida in two stages, taking the orbiter to Ellington Field, Texas, for an overnight stop and finally, on July 5, from Ellington Field to Kennedy Space Center, Florida. Following demate from the SCA Challenger was moved to the OPF to begin final preparations for its first flight on STS-6 early in 1983.
Challenger is the first “operational” shuttle spacecraft. All of its onboard systems have qualified to operate for a minimum of 100 missions without major overhaul. Although Columbia, on its STS-5 flight, was billed as the first operational mission, the onboard systems do not have operational certification. Following the STS-9 mission later in 1983, Columbia will be scheduled to return to Rockwell’s Palmdale plant for major modification, which includes installation of operational systems.
Each new spacecraft to come off the assembly bays in the orbiter manufacturing facility at Palmdale carries improvements in structure, materials and equipment that are not apparent to the observer. Challenger weighs 1,128 kg (2,486 lb.) less than Columbia as a result of weight-saving structural changes that include use of lightweight honeycomb for such things as landing gear doors and vertical tail tip and leading edge.
Much of the secondary support structure in the aft fuselage around the main engine thrust frames has been eliminated or combined with the primary structure. The main engine heatshields are lighter, and in the mid-fuselage the titanium cryogenic tank supports have been replaced with tubing made of boron-aluminum. Challenger weighs 67,876 kg (149,642 lb.) "dry" while Columbia weighs 69,004 kg (152,128 lb.). Loaded with crew, cargo, consumables and experiments, during STS-6 Challenger will weigh 117,267 kg (258,529 lb.) at launch. The STS-6 vehicle, with lightweight External Tank and Solid Rocket Booster casings, will weigh 2,036,856 kg (4,490,498 lb.) at SRB ignition, just 880 kg (1,939 lb.) more than the STS-5 vehicle at launch.
Advanced Flexible Reusable Surface Insulation (AFRSI) blankets, consisting of sewn composite quilted fabric blanket with the same silica tile material sandwiched between outer and inner blanket, have replaced more than 600 Low-temperature Reusable Surface Insulation (LRSI) glass tiles over the two Orbital Maneuvering System pods and the Reaction Control System. AFRSI sheets do not require Thermal protection system silica glass tiles over the rest of Challenger's skin have been densified for improved bonding, based on the lesson learned from Columbia's early tile problems. All 30,000 tiles have been specially treated (densified) to improve their durability.
The Challenger main engines, numbers 2012, 2015 and 2017, will deliver 104 percent of rated thrust, a higher thrust level than the engines on Columbia, which were operated at 100 percent. For each percent increase of thrust over 100 percent, the shuttle gains 454 kg (1,000 lb.) of payload carrying capability.
This higher thrust level was accomplished by incorporating redesigned engine parts into the original engine design. The changes were necessary because of higher temperatures, pressures and pump speeds that the new engines will encounter at the higher thrust level. All the changes were proved out in a very intense engine testing program, which included more than 62,000 seconds of engine firings.
Significant engine changes include: use of higher strength liquid oxygen posts in the main injector due to higher temperatures and pressures; use of a modified fuel pre-burner because of previous erosion of turbine blades and thermal shield nut erosion; and using thicker tubes and redesigning coolant supply lines in the nozzle to accommodate high loads at ignition. The test program and manufacture of the main engines is carried out by the Rocketdyne Division of Rockwell International under the direction of the NASA Marshall Space Flight Center, Huntsville, Alabama.
Each new spacecraft to come off the assembly bays in the orbiter manufacturing facility at Palmdale carries improvements in structure, materials and equipment that are not apparent to the observer. Challenger weighs 1,128 kg (2,486 lb.) less than Columbia as a result of weight-saving structural changes that include use of lightweight honeycomb for such things as landing gear doors and vertical tail tip and leading edge.
Much of the secondary support structure in the aft fuselage around the main engine thrust frames has been eliminated or combined with the primary structure. The main engine heatshields are lighter, and in the mid-fuselage the titanium cryogenic tank supports have been replaced with tubing made of boron-aluminum. Challenger weighs 67,876 kg (149,642 lb.) "dry" while Columbia weighs 69,004 kg (152,128 lb.). Loaded with crew, cargo, consumables and experiments, during STS-6 Challenger will weigh 117,267 kg (258,529 lb.) at launch. The STS-6 vehicle, with lightweight External Tank and Solid Rocket Booster casings, will weigh 2,036,856 kg (4,490,498 lb.) at SRB ignition, just 880 kg (1,939 lb.) more than the STS-5 vehicle at launch.
Advanced Flexible Reusable Surface Insulation (AFRSI) blankets, consisting of sewn composite quilted fabric blanket with the same silica tile material sandwiched between outer and inner blanket, have replaced more than 600 Low-temperature Reusable Surface Insulation (LRSI) glass tiles over the two Orbital Maneuvering System pods and the Reaction Control System. AFRSI sheets do not require Thermal protection system silica glass tiles over the rest of Challenger's skin have been densified for improved bonding, based on the lesson learned from Columbia's early tile problems. All 30,000 tiles have been specially treated (densified) to improve their durability.
The Challenger main engines, numbers 2012, 2015 and 2017, will deliver 104 percent of rated thrust, a higher thrust level than the engines on Columbia, which were operated at 100 percent. For each percent increase of thrust over 100 percent, the shuttle gains 454 kg (1,000 lb.) of payload carrying capability.
This higher thrust level was accomplished by incorporating redesigned engine parts into the original engine design. The changes were necessary because of higher temperatures, pressures and pump speeds that the new engines will encounter at the higher thrust level. All the changes were proved out in a very intense engine testing program, which included more than 62,000 seconds of engine firings.
Significant engine changes include: use of higher strength liquid oxygen posts in the main injector due to higher temperatures and pressures; use of a modified fuel pre-burner because of previous erosion of turbine blades and thermal shield nut erosion; and using thicker tubes and redesigning coolant supply lines in the nozzle to accommodate high loads at ignition. The test program and manufacture of the main engines is carried out by the Rocketdyne Division of Rockwell International under the direction of the NASA Marshall Space Flight Center, Huntsville, Alabama.
In September 1979 the NASA directed Rockwell International’s Shuttle Orbiter Division to add a heads-up display (HUD) system to the shuttle orbiter. This was the result of approximately two years of study activity by NASA and Rockwell with the support of several HUD subcontractors. Rockwell awarded a letter contract to Kaiser Electronics, San Jose, California, in June 1980 to provide a HUD system for the orbiter. The program was progressing on schedule and a pre-production hardware set was delivered to Rockwell in November 1980 for use in the Avionics Development Laboratory for preliminary interface testing.
A heads-up system allows an out-of-the-window view while providing flight commands and information to the flight crew by superimposing this information on a transparent combiner in the out-the-window field of view. The baseline orbiter, like most commercial aircraft, utilizes conventional electromechanical displays on a display panel beneath the glare shield which necessitates that the flight crew look down for information and then up for out-the-window information. During critical flight phases, in particular the approach and landing case, this is not an easy task. In the orbiter with its unique vehicle dynamics and approach trajectories, this situation is even more critical.
Since the orbiter is intended to be in service for several years, it was considered appropriate that it be equipped with this system. In the study phase it was determined that most recent military aircraft include HUD systems and that the airliners used by several European countries also contain HUD’s. Additionally, it was apparent that the display portion of some existing HUD systems would lend themselves to modification for installation in the orbiter. So as to minimize development costs, the HUD system requirements for the orbiter were patterned after existing hardware.
While the display portion of the orbiter system could be similar to existing HUD systems, the drive electronics could not. The orbiter avionics is digital and since minimal impact to the spacecraft was paramount, the HID drive electronics were designed to receive data from the orbiter data buses. Most existing HUD drive electronics use analog data or a combination analog/digital interface. In the orbiter system, the HUD drive electronics utilizes to the maximum extent possible the same data which drives the existing electromechanical display devices to minimize impact to the existing software.
The orbiter display device as designed by Kaiser Electronics uses a Cathode Ray Tube (CRT) to create the image which is then projected through a series of lenses on a combining glass which is very similar to a system they developed and produced for the Cobra Jet Aircraft. Certain orbiter design requirements, including vertical viewing angles, brightness and unique mounting requirements, dictated some changes from the Cobra Jet configuration.
On the orbiter, the HUD will be installed at each flight station (CDR and PLT). Each HUD system is single string although connected to two data buses; redundancy is achieved by the fact that a system is installed at each station (similar to the redundancy system used for present displays), and the fact that the already existing displays can be used in the event of one HUD failure.
The HUD system, which will first be used aboard OV-099 Challenger, is to be installed in line in the production flow for OV-103 and OV-104. It is planned to build a kit which supports installation of the HUD on OV-102. In addition, several other systems are being built for test sites and simulators. A new improved display format is being developed for the heads-up display which will further reduce the CDR/PLT workload during approach and landing. This improved format will be implemented on future Space Shuttle missions.
The HUD is an excellent landing aid and is considered the primary pilot display during this phase. As the system matures, it is anticipated that the HUD will be used for star/land mark sightings as well as rendezvous with other orbiting vehicles, space platforms, etc.
A heads-up system allows an out-of-the-window view while providing flight commands and information to the flight crew by superimposing this information on a transparent combiner in the out-the-window field of view. The baseline orbiter, like most commercial aircraft, utilizes conventional electromechanical displays on a display panel beneath the glare shield which necessitates that the flight crew look down for information and then up for out-the-window information. During critical flight phases, in particular the approach and landing case, this is not an easy task. In the orbiter with its unique vehicle dynamics and approach trajectories, this situation is even more critical.
Since the orbiter is intended to be in service for several years, it was considered appropriate that it be equipped with this system. In the study phase it was determined that most recent military aircraft include HUD systems and that the airliners used by several European countries also contain HUD’s. Additionally, it was apparent that the display portion of some existing HUD systems would lend themselves to modification for installation in the orbiter. So as to minimize development costs, the HUD system requirements for the orbiter were patterned after existing hardware.
While the display portion of the orbiter system could be similar to existing HUD systems, the drive electronics could not. The orbiter avionics is digital and since minimal impact to the spacecraft was paramount, the HID drive electronics were designed to receive data from the orbiter data buses. Most existing HUD drive electronics use analog data or a combination analog/digital interface. In the orbiter system, the HUD drive electronics utilizes to the maximum extent possible the same data which drives the existing electromechanical display devices to minimize impact to the existing software.
The orbiter display device as designed by Kaiser Electronics uses a Cathode Ray Tube (CRT) to create the image which is then projected through a series of lenses on a combining glass which is very similar to a system they developed and produced for the Cobra Jet Aircraft. Certain orbiter design requirements, including vertical viewing angles, brightness and unique mounting requirements, dictated some changes from the Cobra Jet configuration.
On the orbiter, the HUD will be installed at each flight station (CDR and PLT). Each HUD system is single string although connected to two data buses; redundancy is achieved by the fact that a system is installed at each station (similar to the redundancy system used for present displays), and the fact that the already existing displays can be used in the event of one HUD failure.
The HUD system, which will first be used aboard OV-099 Challenger, is to be installed in line in the production flow for OV-103 and OV-104. It is planned to build a kit which supports installation of the HUD on OV-102. In addition, several other systems are being built for test sites and simulators. A new improved display format is being developed for the heads-up display which will further reduce the CDR/PLT workload during approach and landing. This improved format will be implemented on future Space Shuttle missions.
The HUD is an excellent landing aid and is considered the primary pilot display during this phase. As the system matures, it is anticipated that the HUD will be used for star/land mark sightings as well as rendezvous with other orbiting vehicles, space platforms, etc.
A new, lighter-weight motor case has been developed for the Space Shuttle's Solid Rocket Boosters which will increase the shuttle's weight carrying capability by about 363 kg (800 lb.). Weights may vary slightly for each mission. Each booster's motor case used on STS-6 and future flights will weigh about 44,452 kg (98,000 lb.) which is approximately 1,814 kg (4,000 lb.) less than those flown on previous shuttle flights. The weight reduction was achieved by reducing the thickness of the casings' steel skin about two-hundredths to four-hundredths of an inch. Areas of the cases affected by the reduction are the cylindricals attach and stiffener segments.
The thinner casings of the motors will not affect their reusability. Also, the lighter case segments will be interchangeable with the heavier cases flown on previous shuttle flights. The motor cases for the boosters are manufactured by the Rohr Corp. for the motor prime contractor, the Wasatch Division of Morton Thiokol Corp., Brigham City, Utah, under the direction of Marshall Space Flight Center.
Beginning with the External Tank built for use on STS-6, all future tanks will be more than 4,536 kg (10,000 lb.) lighter than the tank which flew on the Space Shuttle's maiden flight in April 1981. Although, the weight of each future tank may vary slightly, each will weigh about 30,390 kg (67,000 lb.). The advantage of using a lighter weight tank is that for each pound of weight reduced from the tank, the shuttle gains almost an extra pound of cargo carrying capability.
The weight reduction was accomplished by eliminating portions of stringers (structural stiffeners running the length of the hydrogen tank), using fewer stiffener rings and by modifying major frames in the hydrogen tank. Also, significant portions of the tank are milled differently to reduce thickness, and the weight of the tank's aft Solid Rocket Booster attachments was reduced by using a stronger, yet lighter and less expensive titanium alloy.
Several hundred pounds were eliminated earlier by deleting an antigeyser line. The STS-5 tank was the first flown with this modification. Development is continuing to further reduce the weight of future tanks.
The External Tank is actually made up of two tanks and a collar-like intertank which connects the two. The two individual tanks carry the liquid hydrogen and liquid oxygen for the Space Shuttle's three main engines. Total length and diameter of the tank remains unchanged due to the weight reduction. The final 34,927 kg (77,000 lb.) tank, which was manufactured earlier than the lighter-weight tank used for STS-6, will be flown on STS-7. The tanks are manufactured by the Michoud Division of Martin Marietta Aerospace, near New Orleans, under the direction of Marshall Space Flight Center.
The thinner casings of the motors will not affect their reusability. Also, the lighter case segments will be interchangeable with the heavier cases flown on previous shuttle flights. The motor cases for the boosters are manufactured by the Rohr Corp. for the motor prime contractor, the Wasatch Division of Morton Thiokol Corp., Brigham City, Utah, under the direction of Marshall Space Flight Center.
Beginning with the External Tank built for use on STS-6, all future tanks will be more than 4,536 kg (10,000 lb.) lighter than the tank which flew on the Space Shuttle's maiden flight in April 1981. Although, the weight of each future tank may vary slightly, each will weigh about 30,390 kg (67,000 lb.). The advantage of using a lighter weight tank is that for each pound of weight reduced from the tank, the shuttle gains almost an extra pound of cargo carrying capability.
The weight reduction was accomplished by eliminating portions of stringers (structural stiffeners running the length of the hydrogen tank), using fewer stiffener rings and by modifying major frames in the hydrogen tank. Also, significant portions of the tank are milled differently to reduce thickness, and the weight of the tank's aft Solid Rocket Booster attachments was reduced by using a stronger, yet lighter and less expensive titanium alloy.
Several hundred pounds were eliminated earlier by deleting an antigeyser line. The STS-5 tank was the first flown with this modification. Development is continuing to further reduce the weight of future tanks.
The External Tank is actually made up of two tanks and a collar-like intertank which connects the two. The two individual tanks carry the liquid hydrogen and liquid oxygen for the Space Shuttle's three main engines. Total length and diameter of the tank remains unchanged due to the weight reduction. The final 34,927 kg (77,000 lb.) tank, which was manufactured earlier than the lighter-weight tank used for STS-6, will be flown on STS-7. The tanks are manufactured by the Michoud Division of Martin Marietta Aerospace, near New Orleans, under the direction of Marshall Space Flight Center.
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