"6_2_7_2.TXT" (3402 bytes) was created on 05-03-88 CREW ESCAPE SYSTEM A telescoping pole has been chosen as the egress method for the Space Shuttle's crew escape system, to be incorporated into the orbiter Discovery prior to the STS-26 flight in August 1988. The selection of the telescoping pole, over an alternative tractor rocket extraction system, was made at NASA Headquarters by National Space Transportation System Director Arnold D. Aldrich following a review of system design, test performance and flight hardware status. "The NASA-contractor team has done a fantastic job in providing both the tractor rocket and telescoping pole systems to support the next Shuttle flight," Aldrich said. "The telescoping pole was selected as it has shown to be safer, simpler to operate, lighter weight and easier to support than the tractor rocket system, while meeting all escape system performance requirements." Tests conducted in February and March 1988, using a fixed pole extending through a hatch-like opening in a C-141 aircraft, demonstrated that the pole would provide adequate orbiter clearance in an emergency egress situation. Navy parachutists, approximating the sizes of astronauts from the smallest to the largest, completed a total of 66 jumps using a lanyard attached to their parachute harness to slide down the pole and descend to a safe landing. Analysis of aerodynamic and photographic data showed that all the jumps provided the necessary clearance margins. The telescoping pole, designed and manufactured at NASA's Johnson Space Center, Houston, is made of light-weight aluminum and steel and weighs 241 pounds. It is about 70 pounds lighter than the tractor rockets system. The rockets also have a 5-year operational shelf life limitation and additional processing requirements between flights. The pole housing attaches to the orbiter's middeck ceiling and is 126.75 inches long. The primary extension is 112.54 inches (arched length), and the end extension is 32.65 inches. For launch and landing, the unextended pole will be oriented toward the closed crew hatch. During on-orbit operations, the pole will repositioned toward the middeck lockers and stowed on the ceiling such that it will not interfere with the various flight crew activities in the middeck area. This decision completes the crew escape system package. Already approved and implemented are the orbiter primary crew hatch jettison capability and crew support equipment -- a partial pressure suit, oxygen equipment, a parachute, a life raft and survival equipment for each crew member. The escape system provides crew escape capability from the orbiter during controlled, gliding flight following failures or difficulties during ascent or entry where landing at a suitable landing field cannot be achieved. Previous procedures for ascent contingency aborts, where no landing site could be reached, required orbiter ditching in the ocean, a condition which has been shown by structural analysis to be extremely hazardous. The side hatch jettison system also can be highly beneficial for certain ground contingencies following non-normal landings. A crew escape slide, similar to those provided on commercial airliners, has been implemented in conjunction with the jettisonable hatch to support rapid post-landing contingency egress. CHANGES TO THE EMERGENCY EGRESS SYSTEM AT PAD 39-B May 1988 A number of modifications have been made to the emergency egress system at Launch Pad 39-B to increase the margins of personnel safety. Two baskets have been added to the 195-foot level of the Launch Pad Fixed Service Structure. Previously, there were five baskets rated to hold four people weighing an average of 190 pounds. Officials decided that the maximum individual weight rating was not sufficient and increased it to 220 pounds per person, which takes into account the weight of life-support apparatus, such as air tanks, which escapees are likely to be wearing. Considering the bulk of the life-support apparatus, officials also have decided that the baskets will be rated to hold three people each instead of four, and will have a nominal operating weight capacity of 660 pounds. However, four people will be permitted if necessary. The maximum carrying capacity of each basket is 880 pounds. The baskets were modified at KSC's Launch Equipment Shop. A side exit to the basket was incorporated, a flame-protective covering was added over the existing webbed material and an anti-roll-back brake was added to ensure the basket comes to rest as quickly as possible. The braking mechanism for the baskets consists of a series of increasing-density steel chains that drag through the sand in the landing zone, decelerating the basket to a final stop. The new brake holds the baskets at their furthest extent of travel. Before, the baskets would stop temporarily and then begin to move backwards before coming to a complete stop. A rope arresting net at the end of the slidewire provides a redundant stopping point for the basket in the unlikely event the deceleration system fails. At the stopping point, personnel exit through the side opening. The basket will hang approximately 2-3 feet off the ground. The stainless steel sidewires will be restrained against vertical movement to limit the variance in basket height as occupants exit. Upon exiting, the crew members will make a decision as to whether to enter armored personnel carriers and drive to safety, or to enter an underground concrete bunker. A new underground, steel-reinforced concrete bunker was built and provides easier access. The bunker's roof is 1-foot thick and the walls are 15- inches thick. It is 20-feet long by 13.4-feet wide, and is located just to the south of the slidewire basket termination area. The bunker contains emergency air for breathing, an emergency shower, a telephone and four fold-down bunks. It features a five-foot-wide roll-up door in addition to a standard swing door. The roll-up door will be open during the final launch countdown for easier access in the bunker. Fire-protection plating was added to the Orbiter Access Arm and on the 195-foot level of the Fixed Service Structure (FSS). Previously, there was an open-grate floor, as used on the rest of the pad levels. It is from this level that the crew enters and exits the Space Shuttle. Additional fire detectors have been installed on the FSS to provide better coverage on the 195-foot level and the Orbiter. The fire water spray system also has been upgraded for better coverage on the egress paths. The lighting has been upgraded on the 195-foot level of the FSS and at the slidewire landing area in the case of a night emergency. Emergency procedures and documents also have been revised. "6_2_7_4.TXT" (17028 bytes) was created on 11-28-88 SPACE SHUTTLE TRANSOCEANIC ABORT LANDING (TAL) SITES Planning for each Space Shuttle mission includes provi- sions for an unscheduled landing at contingency landing sites in the U.S. and overseas. Several unscheduled landing scenarios are possible, ranging from adverse weather condi- tions at the primary and secondary landing sites to mechani- cal problems during the ascent and mission phases that would require emergency return of the orbiter and its crew. The Transoceanic Abort Landing (TAL) is one mode of un- scheduled landing. The orbiter would have to make an un- scheduled landing if one or more of its three main engines failed during ascent into orbit, or if a failure of a major orbiter system, such as the cooling or cabin pressurization systems, precluded satisfactory continuation of the mission. The abort mode would depend on when in the ascent phase an abort became necessary. The TAL abort mode was developed to improve the options available if failure occurred after the last opportunity for a safe return to the launch site, but before the first opportunity to fly once around the Earth and return to a landing site. A TAL would be declared between roughly T+2:30 minutes and Main Engine Cutoff (MECO), about T+8 minutes, with the exact time depending on the payload and mission profile. A TAL would be made at one of four designated sites, two in Africa and two in Spain: Ben Guerir Air Base, Morocco; Yundum International Airport, Banjul, The Gambia; Moron Air Base, Spain; and Zaragoza Air Base, Spain. Although Banjul has many of the same features as the three other TAL sites, it is formally called an augmented emergency landing site. Each TAL site is covered by a separate international agreement, but all four are considered augmented because they have Shuttle-specific landing aids and NASA and Defense Department personnel available during a launch. Space Shuttles are launched eastward over the Atlantic Ocean from KSC for insertion into equatorial orbits. In a TAL abort, the orbiter continues on a ballistic trajectory across the Atlantic to land at a predetermined runway. The four sites NASA has designated for TALs have been chosen in part because they are near the nominal ascent ground track of the orbiter, which would allow the most efficient use of main engine propellant. Depending on mission requirements, an orbiter follows an orbital insertion inclination between 28.5 and 57 degrees, with the lower inclination preferred in most instances be- cause it allows for a higher maximum payload weight. High or low inclination launches require different contingency land- ing site. BEN GUERIR AIR BASE, MOROCCO The primary TAL site for a low inclination launch is the Ben Guerir Air Base in Morocco. Ben Guerir has also been designated a weather alternate TAL site for high inclination launches because of its geographic location and its landing support facilities. Ben Guerir replaced a TAL site at Dakar, Senegal, which NASA concluded was unsatisfactory due to run- way deficiencies and geographic hazards. Morocco is located along the northwest coast of Africa, between 27 degrees and 37 degrees north. It is shielded from the desert of northern Africa by the Atlas mountains on the eastern border of the country. A cool ocean current runs along the west coast, similar to the situation in southern California, which makes the coastal areas subject to low clouds and fog most of the year. The interior sections of the country are generally arid, with most precipitation oc- curring from October to April and concentrated in the north. Ben Guerir was designated as a TAL site in September 1986. Located on a flat, rocky, desert plain about 36 miles north of Marrakech, Ben Guerir is a former Strategic Air Command Base abandoned in 1963. It has one runway, oriented in a north-south direction, which is 14,000 by 200 feet with a 720-foot overrun at the north end. The runway surface has been rejuvenated, and an operations and storage building added. NASA also put in place additional fire-fighting equipment, personnel transport vehicles and other ground support equipment. Communications include three communica- tion satellite circuits. YUNDUM AIRPORT, BANJUL, THE GAMBIA Yundum Airport has been named an alternate to Ben Guerir and Moron Air Base. Because of its in-plane location, Yundum could also be used for a late TAL and to accomplish a TAL in the event of in-flight failure of a second engine. Yundum was named a TAL site in September 1987. Yundum is The Gambia's international airport, located adjacent to the country's capital, Banjul. The airport is located on a flat plain seven miles inland from the Atlantic and six miles south of the Gambia River. The Gambia has a dry season which extends from November to May, during which weather condi- tions are generally good, the only difficulty being lowered runway visibility due to dust. The airport lies almost directly below the 28.5-degree flight path, hence its designation as an in-plane contin- gency site. The runway is 11,810 feet by 150 feet wide, with 200- and 400-foot overruns, and 25-foot paved shoulders. Three communications satellite circuits are used for com- munication, along with two commercial Gambian telephone cir- cuits. MORON AIR BASE, SPAIN The Moron Air Base has been designated a weather alter- nate TAL to the primary TAL, Ben Guerir, for low inclination launches. Moron was designated a TAL site in 1984. Moron can also serve as the secondary site for high inclination launches. It is located about 35 miles southeast of Sevilla and 75 miles northeast of Rota Naval Station. Although Moron is close to the foothills of the Sierra de Ronda mountain chain, most of the surrounding countryside is flat with a few hills and shallow valleys. Elevations vary from 200 to 400 feet above sea level. The weather is generally good with no associated unusual weather phenomena. The Moron AB has an 11,800- by 200-foot runway with 1,000-foot overruns and a 50-foot asphalt-stabilized shoulder. Communication at Moron includes a dedicated cir- cuit to KSC/Cape Canaveral Air Force Station via Goddard Space Flight Center and the NASCOM Madrid Switching Center, three circuits via satellite, and an 800-line automatic dial exchange. ZARAGOZA AIR BASE, SPAIN Zaragoza AB was designated a TAL site in 1983. It is the primary TAL site for high inclination launches and like Moron is a Spanish base used by both the U.S. and Spain. Lo- cated northwest of the town of Zaragoza, it has two parallel runways, one 9,923 feet by 197 feet and the other 12,109 feet by 197 feet. The longer runway has 1,000 feet of over- run and is used primarily by the U.S. Air Force. Its length and the prevailing winds make the longer runway the most suitable for Shuttle use. Communications at Zaragoza include one dedicated circuit to KSC/CCAFS via Goddard and the Madrid switch, three cir- cuits via satellite, and an automated dial exchange. An AUTOVON voice circuit is available. SHUTTLE SUPPORT EQUIPMENT AT TAL SITES NASA has enhanced each of the four TAL sites with equip- ment to support an orbiter landing, including: --Navigation and Landing Aids: NASA has equipped each of the four sites with Shuttle-specific navigation and land- ing aids. The TACAN, or Tactical Air Navigation system, works in conjunction with the MSBLS system, or Microwave Scanning Beam Landing System. Together the two will provide the orbiter with all the necessary data to make a safe land- ing. The TACAN is positioned to provide distance and bearing information to the orbiter. The orbiter will be able to lock on to the TACAN while still several hundred miles out over the Atlantic and receive precise guidance information to ef- fect a successful alignment with the runway. The MSBLS sys- tem is accurate within five hundredths of a degree and provides the proper elevation landing angle from about 30,000 feet to touchdown. Lighted aim points include six strobe lights located at 6,500 feet from each runway and spaced about two feet apart on the runway centerline to a point 6,490 feet from each threshold. They assist the orbiter crew in locating the PAPI lights. PAPI, Precision Approach Path Indicator Lights, with as- sociated strobes, will be utilized by the orbiter crew to verify outer glide slope during a landing. Two sets are used to accommodate high and low wind scenarios. High wind PAPI lights are 6,500 feet on centerline prior to each threshold and low wind PAPI lights are 7,500 feet on centerline prior to each threshold. Ball/bar lights will be used by the Shuttle astronauts to verify proper inner glide slope during landing. The ball/bar lights are installed along both runways. The ball light is 1,700 feet from the runway threshold, the bar light 2,200 feet. Distance-to-go markers will allow the crew to determine the distance remaining to the end of either runway during landing and rollout. These markers are installed on each side of the runway, 1,000 feet apart, starting from each threshold to the barrier. Xenon lights are a high intensity flood light system, complete with diesel generators, which will provide runway lighting in the event of a night TAL. The system is portable and consists of two sets of three lights. A set is installed on each side of the runway at the threshold, 150 feet from the centerline on a raised platform truck. The ball/bar and PAPI lights, lighted aim points, distance-to-go markers and Xenon lights are installed prior to each Shuttle launch and dismantled after it is completed and stored away. --Weather Equipment: Each TAL site has an automated weather station that transmits via the Geostationary Opera- tional Environment Satellite (GOES). During a Shuttle launch, the Defense Department will provide weather observa- tions at two of the TAL sites, Moron and Zaragoza, Spain, while Morocco and The Gambia will handle this function within their own countries. Responsibility for weather forecasting will always rest with the NASA Shuttle Meteorol- ogy Group (SMG). --Shuttle Orbiter Arresting System: Three of the TAL sites, Yundum, Moron and Zaragoza, are equipped with the Shuttle orbiter arresting system (SOAS), which is a net bar- rier installed prior to and dismantled after a successful launch. The SOAS, a self-contained system which can be in- stalled in eight hours by a crew of eight, is installed about 800 feet from the end of the pavement to safely stop an orbiter vehicle if necessary. Ben Guerir with its longer runway does not require the SOAS. --Dedicated Orbiter Ground Support Equipment: Special orbiter ground support equipment has also been installed and is stored on-site between missions. These are a hatch open- ing tool, landing gear lock pins, grounding cable, tow bar, tow bar adapter and towing vehicle. --Fire, Crash and Rescue Resources: A team of NASA fire, crash and rescue personnel will be on-site during mis- sion support, supplemented by trained personnel from the country in question. Fire-fighting equipment is permanently stored at Ben Guerir; at Banjul, local fire equipment is used, and at the two Spanish bases U.S. Air Force equipment is available. --Aircraft Support: U.S. Defense Department C-130 aircraft are positioned at Ben Guerir, the primary TAL site for low inclination launches, and at Banjul and Moron Air Base. For high inclination launches, a C-130 would be posi- tioned at Zaragoza Air Base. Each aircraft is staffed with medical personnel and is capable of transporting the entire Shuttle crew. The C-130s will also be used to transport TAL ground personnel between sites. Additional aircraft, person- nel and equipment will be flown over from the U.S. to bring the orbiter back. Pararescue personnel are available to as- sist with search and rescue operations and medical treatment in the event of a crew bailout from the orbiter. WHEN A TAL OCCURS About a week prior to a Shuttle launch, a team of U.S. personnel will arrive and activate the TAL sites identified for that mission. This mission support team will include up to about 50 government personnel headed by the NASA ground operations manager. The Defense Department medical team will arrive on-site 24 hours prior to launch. If a TAL is declared, the TAL site will be notified by NASA that the Shuttle is going to land there. The U.S. State Department will notify the country involved and the air space will be cleared. The time from declaration of a TAL to a landing is es- timated at about 20-25 minutes. Once the Shuttle crew com- mander punches the TAL call into the pre-programmed orbiter computers, the vehicle will automatically be steered toward the landing site. The orbiter will roll heads-up before main engine cutoff and all extra fuel will be dumped to in- crease vehicle performance by decreasing its weight, properly placing the center of gravity and lowering landing weight. The Shuttle will automatically fly to an altitude of about 360,000 feet and the remaining engines will cut off at the correct velocity. The external tank will be jettisoned after engine shutdown, as in a nominal launch, and then tumbled to insure that it does not glide into the Earth's atmosphere. A pre-loaded reentry program will then go into effect, with the orbiter encountering the atmosphere and a normal reentry planned. Ten minutes before landing, normal com- munications will resume through the Tracking and Data Relay Satellite (TDRS). The orbiter crew will contact the TAL site on UHF radio and begin their approach to the field in preparation for landing. Data received from the TAL TACAN is received and used to update the orbiter's inertial guidance system 200 miles from touchdown as the spacecraft slows to Mach 7. At landing minus 6 minutes, the orbiter will enter what is considered to be the terminal area. At this point its al- titude is still quite high, 82,000 feet, and its speed supersonic--Mach 2.5. Its flight is akin to a conventional aircraft's except that its speedbrakes will be left open to provide greater stability during supersonic flight. Approximately five minutes before touchdown, the orbiter will pass over the center of the runway with the speed drop- ping to Mach 1. About four minutes before landing, the crew commander will take over manual control of the spacecraft. This will be just prior to a maneuver known as intercepting the heading alignment circle. This is a large 270 degree turn to align the orbiter with the center line of the run- way. At landing minus 2 minutes, the orbiter will enter its final approach at an altitude of 13,000 feet. The speedbrakes are closed at an altitude of 3,000 feet. At an altitude of 1,800 feet and 7,500 feet from the end of the runway, the commander begins a preflare maneuver to pull up from a glide angle of 17 degrees to a more gentle slope of one and a half degrees. Touchdown speed is 195 knots. The Shuttle flight crew is expected to give its first report to Mission Control at T+50 minutes. Exit from the or- biter will occur at about one hour and ten minutes into the launch cycle. At about T+4 hours, the crew will depart the TAL site aboard the C-130 and will be taken, if uninjured, to an evacuation site--the nearest U.S. military base--or to appropriate medical facilities if injured. Some 16 hours into the launch, a KC-135 aircraft will arrive at the evacuation site and, depending on the crew sleep cycle, will take the crew back to the U.S. The flight crew will remain together unless medical circumstances dictate otherwise. Ground Operations Once the crew has left the orbiter, the crew hatch will be closed and special equipment installed to prepare the vehicle for transport. It will then be towed to a remote deservicing park site. Safing and deservicing of the orbiter will be initiated by the Rapid Response Team. The RRT includes up to 50 workers and equipment, most of it coming from Edwards AFB, Calif., where the majority of Shuttle landings have taken place. Depending on the situation, the RRT should arrive at the TAL site within a day aboard a C-141 aircraft. Following the advance RRT contingent, additional person- nel and equipment will brought in to effect the orbiter tur- naround. NASA estimates it will take some 55 C-141 aircraft and 30 C-5A aircraft sorties and a total of about 450 per- sonnel to complete turnaround. The TAL site ground opera- tions manager will be in charge. A Mishap Investigation Team (MIT) will also travel im- mediately to the site to collect data on the unscheduled landing. Payloads and/or airborne support equipment will remain aboard the orbiter for the flight back to Kennedy Space Cen- ter unless the capability of the Shuttle Carrier Aircraft (SCA), landing site location or other requirements dictate otherwise.