National Basketball Association

Today, the NBA has reached 30 franchises and continues to evolve as one of the premier sports leagues in the world. Unlike the shuttle, this future launcher and associated crew exploration vehicle will have a launch escape system to save the crew in the event of a disaster. In 1996 the NBA created a women's league, the Women's National Basketball Association, and in 2002 created an affiliated minor league, the National Basketball Development League. This contrasts with the current shuttle where astronauts and heavy cargo are launched in a single vehicle. The NBA is now televised in 212 nations in 42 languages. This technology would be used to develop two separate launchers, one for manned missions and the other for unmanned heavy cargo. An increasing number, though, have moved directly from playing elsewhere in the world to starring in the NBA, such as 2002 NBA Rookie of the Year Pau Gasol of Spain, 2002 first pick in the NBA Draft Yao Ming of China, and 2004 Olympic Tournament MVP Manu Ginobili of Argentina. NASA plans on using modified shuttle components to build an expendable Shuttle Derived Launch Vehicle.

Initially, many of these players, such as 1994 NBA MVP Hakeem Olajuwon of Nigeria, first played NCAA basketball to enhance their skills. NASA currently uses these for unmanned launches, and plans to use them for future manned launches. A growing number of NBA star players also began coming from other countries. Another approach is lower cost expendable launch vehicles. The 1992 Olympic basketball Dream Team, the first to use current NBA stars, featured Michael Jordan, Larry Bird, and Magic Johnson. Like the X-33, the X-30 encountered major technical difficulties, primarily due to the system complexity and materials required for hypersonic flight, and was finally cancelled. The 1990s also saw greater globalization. The official name was the Rockwell X-30.

During the 1990s, Jordan went on to lead the Bulls to six titles. Department of Defense, but passenger-carrying civilian versions were planned, sometimes called the "New Orient Express". By 1989, further expansion had raised the number of teams in the league to 27. It was originally investigated by the U.S. Michael Jordan, entered the league in 1984 with the Chicago Bulls, providing an even more popular star to support growing interest in the league. It would achieve much of orbital velocity while still within the upper atmosphere. Bird went on to lead the Celtics to three titles, and Johnson went on to lead the Lakers to five. This would be launched and landed horizontally like an airliner.

That same year, rookies Larry Bird and Magic Johnson joined the Boston Celtics and Los Angeles Lakers, respectively, initiating a period of significant growth in fan interest in the NBA throughout the country and the world. Another variant of SSTO is a hypersonic, scramjet-powered, airbreathing vehicle. The league added the ABA's innovative three-point field goal beginning in 1979 to open up the game. During design that program increased in complexity and development cost, encountered problems and was finally cancelled. Following the 1976 season, the leagues reached a settlement that provided for the addition of four ABA franchises to the NBA, raising the number of franchises in the league at that time to 22. NASA evaluated several concepts in the 1990s, and selected the X-33, which would eventually have been the Venturestar. The NBA expanded rapidly during this period, one purpose being to tie up most viable cities. One approach is Single Stage To Orbit (SSTO), which would be 100% reusable and use a single stage.

The ABA also succeeded in signing a number of major stars, including Julius Erving, in part because it allowed teams to sign college undergraduates. In general future designers look to less complex, more reliable launch systems with lower maintenance costs. However, the NBA's leading scorer, Rick Barry jumped to the ABA, as did four veteran referees -- Norm Drucker, Earl Strom, John Vanak and Joe Gushue. Nixon in 1971 [4], the operational costs, flight rate, payload capacity, and reliability have been worse than anticipated. The NBA landed the most important college star of the era, Kareem Abdul Jabbar (then known as Lew Alcindor), who together with Oscar Robertson led the Milwaukee Bucks to a title in his second season, and who later played on five Laker championship teams. While it was developed within the original development cost and time estimates given to President Richard M. The leagues engaged in a bidding war for talent. Opinions differ on the lessons of the Shuttle.

In 1967, the league faced a new external threat with the formation of the American Basketball Association. Advances in technology over the last decade have made probes smaller and lighter, and as a result unmanned probes and communications satellites can use relatively cheap and reliable expendable rockets, including Delta launcher, and Atlas V. Through this period, the NBA continued to strengthen with the shift of the Minneapolis Lakers to Los Angeles, the Philadelphia Warriors to San Francisco, and the Syracuse Nationals to Philadelphia, as well as the addition of its first expansion franchises. The Shuttle's history of unexpected delays also makes it liable to miss the narrow launch windows. Russell's rivalry with Chamberlain became one of the great individual rivalries in the history of team sports. Following the Challenger disaster, carrying in the shuttle payload bay the powerful liquid fueled Centaur upper stages planed for interplanetary probes was ruled out. Center Wilt Chamberlain entered the league in 1959 and became the dominant individual star of the 1960s, setting new records in scoring and rebounding. NASA's plan for using the shuttle to launch all unmanned payloads declined, then was discontinued.

In 1956, rookie center Bill Russell joined the Boston Celtics, who already featured guard Bob Cousy and coach Red Auerbach, and went on to lead the club to eleven NBA titles in thirteen seasons. No other launch vehicle had the shuttle's payload capability or could return large items from the space station to earth. To liven up play, the league introduced the 24 second shot clock in 1954. Even though the initially planned Space Station Freedom was signficantly scaled back, the shuttle was still vital to service it. During this period, the Minneapolis Lakers, led by center George Mikan, won five NBA Championships and established themselves as its first dynasty. During development, shuttle features were primarily chosen based on capability required to service the future space station. 1950 also saw the NBA integrate, with the addition of African American players by several teams including Chuck Cooper with the Boston Celtics, Nat "Sweetwater" Clifton with the New York Knicks, and Earl Lloyd with the Washington Capitols. The result is high labor cost, with around 25,000 workers in Shuttle operations and labor costs of about $1 billon per year.

Louis; the Royals from Rochester to Cincinnati, the Pistons from Fort Wayne to Detroit. Furthermore, because in some cases there are no survivable abort modes, many pieces of hardware simply must function perfectly and so must be carefully inspected before each flight. The Hawks shifted from "Tri-Cities" to Milwaukee and then to St. Because loss of crew is unacceptable, the primary focus of the Shuttle program is to return the crew to Earth safely, which can conflict with other goals, namely to launch payloads cheaply. While contracting, the league also saw its smaller city franchises move to larger cities. Instead, this turnaround process usually takes months, however once Columbia was launched twice within 56 days. In 1950, the NBA consolidated to eleven franchises, a process that continued until 1954, when the league reached its smallest size of eight franchises, all of which are still in the league (the Knickerbockers, Celtics, Warriors, Lakers, Royals/Kings, Pistons, Hawks, and Nationals/76ers). After landing, the orbiter would be checked out and start "mating" to the rest of the system (the ET and SRBs), and be ready for launch in as little as two weeks.

Following the 1949 season, the BAA agreed to merge with the NBL, expanding the rechristened National Basketball Association to seventeen franchises located in a mix of large and small cities, as well as large arenas and smaller gymnasiums and armories. The Shuttle was originally conceived to operate somewhat like an airliner. For instance the 1947 ABL finalist Baltimore Bullets moved to the BAA and won its 1948 title, followed by the 1948 NBL champion Minneapolis Lakers who won the 1949 BAA title. Some reasons for higher than expected operational costs can be ascribed to:. During its early years, though, the quality of play in the BAA was not obviously better than those other leagues or among leading independent clubs such as the Harlem Globetrotters. Another way to calculate launch cost is the incremental expense of adding a single additional shuttle mission, which is is about $100 million. Although there had been earlier attempts at professional basketball leagues, including the American Basketball League and the National Basketball League, the BAA was the first league to attempt to play primarily in large arenas in major cities. Some of this can be attributed to operating beyond the 10-year anticipated lifespan of each Shuttle, and higher than anticipated maintenance costs.

The Basketball Association of America was founded in 1946 by the owners of major sports arenas in the Northeast and Midwest, most notably Madison Square Garden in New York City. This has been much more expensive than anticipated. There has been only one exception to date: Jerry West won the award in 1969 (the award's first season) even though his Los Angeles Lakers did not win the championship. This includes all related costs such as maintenance, ground facilities, training, etc., and divides that figure by the number of shuttle flights. In addition, the league awards an NBA Finals Most Valuable Player Award, which nearly always goes to a member of the winning team, though not by rule. There are various ways to calculate costs -- the $500 million figure inclues all operational details of maintaining and servicing the Shuttle fleet. Each player and major contributor, including coaches and the general manager, on the winning team receive a championship ring. Per launch costs are roughly $500 million today.

The victor in the NBA Finals wins the Larry O'Brien Championship Trophy. However, this does not fully explain the high shuttle operational costs. The final playoff round, a best-of-seven series between the victors of both conferences, is known as the NBA Finals, and it is held annually in June. Nixon in 1971 [3]. For the final round (NBA Finals), the series follows a 2-3-2 pattern. In fact when discounting inflation, the shuttle development program was within the initial cost estimate given to President Richard M. In every round except the NBA Finals, the best of seven series follows a 2-2-1-1-1 pattern, meaning that one team will have home court in games 1, 2, 5, and 7, while the other plays at home in games 3, 4, and 6. When evaluating shuttle development costs in later-year dollars, this superficially appeared to be a large cost overrun in the program.

Since the NBA does not re-seed teams, the playoff bracket in each conference uses a traditional design, with the winner of the series matching the 1st and 8th seeded teams playing the winner of the series matching the 4th and 5th seeded teams, and the winner of the series matching the 2nd and 7th seeded teams playing the winner of the series matching the 3rd and 6th seeded teams. Between when the program began in 1972, and first flight in 1982, inflation increased prices over 200%. Thus, all but one team in each conference are eliminated from the playoffs. suffered from severe inflation. In the next round, the successful team plays against another advancing team of the same conference. During the 1970s the U.S. Each team plays a rival in a best-of-seven series, with the first team to win four games advancing into the second round, while the other team is eliminated from the playoffs. One reason behind this apparent failure is inflation.

The playoffs follow a tournament format. Although the final design differs from the original concept, the project was still supposed to meet USAF goals and be much cheaper to fly in general. Therefore, the team with the best regular season record in the league is guaranteed home court advantage in every series it plays. Although it did operate as the world's first reusable crew-carrying spacecraft, it did not improve on those parameters in any meaningful way, and is considered by some to have failed in its original purpose. This means that, for example, if the team who receives the 6 (six) seed has a better record than the team with the 3 (three) seed (seeded thus by virtue of a divisional championship), the 6 seed would have home court advantage, even though the other team has a higher seed. It was intended to improve greatly on the previous generation of single-use manned and unmanned vehicles. The team in each series with the better record has home court advantage, including the First Round. The original mission of the Shuttle was to operate at a high flight rate, at low cost, and with high reliability.

Since the first seed plays the eighth seed, the second seed plays the seventh seed, the third seed plays the sixth seed, and the fourth seed plays the fifth seed in the playoffs, having a higher seed generally means you will be facing a weaker team. [2]. Having a higher seed offers several advantages. NASA's budget for 2005 allocates 30%, or $5 billion, to Space Shuttle operations. Although the playoff brackets are not reseeded, home-court advantage is based strictly on regular-season record, without regard to whether a team won its division. The total cost of the program has been $145 billion as of early 2005 ($112 billion of which was incurred while the program was operational) and is estimated at $174 billion when the Shuttle retires in 2010. However, the seeding system has one feature that is unusual in North American sports; division champions do not necessarily have home-court advantage in the playoffs. While the Shuttle has been a reasonably successful launch vehicle, it has been unable to meet its goal of radically reducing flight launch costs, as the average launch expenditures during its operations up to 2005 accumulates to $1.3 billion [1], a rather large figure compared to the initial projections of $10 to $20 million.

The remaining five seeds are determined by taking the five teams with the next-best records from among the non-division winning teams in the conference. The Columbia Accident Investigation Board called this tendency the "normalization of deviance" -- a gradual acceptance of abnormal events simply because they haven't been catastrophic to date. The top three seeds for each conference are determined by taking the winners of the conference's three divisions and ranking them by regular season record. Over time NASA managers gradually accepted more tile damage, similar to how O-ring damage was accepted. The NBA Playoffs begin in late April, with eight teams in each conference qualifying for the playoffs. The original shuttle operational specification said the orbiter thermal protection tiles were designed to withstand virtually no debris hits at all. There are also two All-Rookie teams, consisting of the top first-year players regardless of position. The foam had not been designed or expected to break off, but had been observed in the past to do so without incident.

There are two All-Defensive teams, consisting of the top defenders at each position. Columbia failed because of damaged thermal protection from foam debris that broke off the external tank during ascent. There are three All-NBA teams, consisting of the top players at each position, with first-team status being most desirable. Challenger's O-ring eroded completely through, with fatal results. The postseason teams are the All-NBA Teams, the All-Defensive Teams, and the All-Rookie Teams; each consists of five players. Unfortunately NASA and Thiokol senior managers overruled him and allowed the launch to proceed. Additionally, The Sporting News awards an unofficial (but widely recognized) NBA Executive of the Year Award to the general manager who is adjudged to have done the best job for his franchise. He raised concerns that the unusually cold temperatures would stiffen the O-rings, preventing a complete seal.

The NBA Most Valuable Player Award is given to player deemed the most valuable for that season. Morton Thiokol designed and manufactured the SRBs, and during a pre-launch conference call with NASA, the Thiokol engineer most experienced with the O-rings pleaded repeatedly to cancel or reschedule the launch. The NBA Coach of the Year Award is awarded to either the best coach in the league or the coach that has made the most positive difference to a team. Instead of finding out why, managers felt because it had not previously eroded by more than 30%, that this was not a hazard as there was "a factor of three safety margin". The NBA Defensive Player of the Year Award is awarded to the league's best defender. In the case of Challenger, an O-ring which should not have eroded at all did, in fact, erode on earlier shuttle launches. The NBA Most Improved Player Award is awarded to the most improved player. In both cases a mind set among senior managers developed that concerns had to be objectively proven rather than simply suspected.

The NBA Rookie of the Year Award is awarded to the best rookie player. A heavily layered, procedure-oriented bureaucratic structure inhibited necessary communication and action. The NBA Sixth Man Award is given to the best player coming off the bench (not starting for his team). In both cases the vehicle gave ample warning beforehand of abnormal problems. It is during this time that voting begins for individual awards, as well as the selection of the honorary league-wide postseason teams. In both cases, junior engineers were greatly concerned about possible problems, but these concerns were not properly communicated to or understood by senior NASA managers. In April, the regular season ends. In both cases events happened which were not planned for or anticipated.

Major trades are often completed right before the trading deadline, making that day a hectic time for general managers. While the technical details of the accidents are quite different, the organizational problems show remarkable similarities. After this date, teams are not allowed to exchange players with each other for the remainder of the season, although they may still sign and release players. This gives a 2% death rate per astronaut per flight. Shortly after the All-Star break is the league's trade deadline. Two Shuttles have been destroyed in 114 missions, both with the loss of the entire crew of seven:. Other attractions of the All-Star break include the got milk? Rookie Challenge game, which pits the best rookies and the best second-year players against each other; the Foot Locker Three-Point Shootout, a competition between players to see who is the best 3-point shooter; and the Sprite Rising Stars Slam Dunk contest, to see which player dunks the ball in the most entertaining way. † Satellites deployed
* This was flight STS-80, during November 1996.

The player with the best performance during the game is rewarded with a Game MVP award. Whilst all three Orbiters are externally very similar, they have minor internal differences; new equipment is fitted on a rotating basis as they are maintained, and the newer Orbiters tend to be structurally lighter. Then, East faces West in the All-Star game. Individual Orbiters are both named, in a manner similar to ships, and numbered, using the NASA Orbiter Vehicle Designation system. Coaches vote to choose the remaining 14 All-Stars. After landing the vehicle stands on the runway to permit the poisonous hydrazine fumes used for part of the attitude control during descent to dissipate. Fans are balloted throughout the United States, Canada and through the Internet, and the top vote-getters at each position in each conference are given a starting spot on their conference's All-Star team. Landing speed is very high -- 213 to 255 mph, vs 160 mph for a jet airliner.

In February, the NBA regular season is interrupted to celebrate the annual NBA All-Star Game. It glides to landing with a glide angle of 4:1. Following the recent changes to the National Hockey League's scheduling format, the NBA is now the only major league in which all the teams play each other during the regular season, and where a season ticket holder can see every team in the league come to town in any one season. In the lower atmosphere the orbiter flies much like a conventional glider, except for a much higher descent rate, over 10,000 feet per minute (roughly 20 times that of an airliner). A team can therefore have a relatively easy or difficult schedule, depending on the division and conference it is located in. Attitude control is achieved from a mixture of RCS thrusters and control surfaces. A team faces opponents in its own division four times a year, teams from the other two divisions in its conference either three or four times, and teams in the other conference twice apiece. This is achieved by performing s-curves at up to 70 degree bank angle.

Schedules are not identical for all teams. In addition, the standard reentry aims deliberately high- the vehicle needs to bleed off extra altitude and speed to reach the landing site. In the regular season, each team plays 82 games, which are divided evenly between home and away games. The vehicle attitude is controlled to take on a nose up attitude of up 40 degrees to maximise drag. The NBA regular season begins in the first week of November. The vehicle will then start significantly entering the atmosphere at about 400,000 ft doing around Mach 25. After training camp, a series of preseason exhibition games are held. However the reentry can be and has (once) been flown manually.

Teams have the ability to assign players with less than two years of experience to the NBA development league. The entire reentry, except for the lowering of the undercarriage, is under complete computer control. Training camps allow the coaching staff to evaluate players (especially rookies), scout the team's strengths and weaknesses, prepare the players for the rigorous regular season, and determine the 12-man active roster (and a 3-man inactive list, if needed) with which they will begin the regular season. This OMS firing is done roughly halfway around the globe from the landing site. Following the summer break, teams hold training camps in October. The deceleration of the Shuttle lowers its orbit perigee down into the atmosphere. . The vehicle begins reentry by firing the OMS engines in the opposite direction to the orbital motion for about three minutes.

NBA Entertainment and NBA TV studios are directed out of offices located in Secaucus, New Jersey. The Shuttle then fires the OMS engines to circularize the orbit and avoid reentry. The league's several international and individual team offices are directed out its head offices located in the Olympic Tower at 645 Fifth Avenue in New York City. At this point the Shuttle is still slightly suborbital, since the trajectory intersects the atmosphere. The league adopted the name National Basketball Association in the fall of 1949 after merging with the rival National Basketball League. The tank then falls to largely burn up in the atmosphere, with some fragments falling into the Indian Ocean. The league was founded in New York City on June 6, 1946 as the Basketball Association of America (BAA). Before complete depletion of propellant (running dry would destroy the engines) the main engines are shutdown, and the empty external tank is released by firing explosive bolts.

The National Basketball Association, more commonly referred to as the NBA, is the world's premier men's professional basketball league and one of the major professional sports leagues of North America. Finally, in the last tens of seconds of the main engine burn, the mass of the vehicle is low enough that the engines must be throttled back to limit vehicle acceleration to 3g, largely for astronaut health and comfort. NBA Coach of the Year Award. The vehicle continues to climb and takes on a somewhat nose-up angle to the horizon — it uses the main engines to gain and then maintain altitude whilst it accelerates horizontally towards orbit. NBA Rookie of the Year Award. However, as the burn continues, the weight of the propellant reduces, the ever-lighter vehicle produces more and more acceleration until the thrust to weight ratio exceeds 1 again and the vehicle can hold itself up. NBA Defensive Player of the Year Award. The vehicle at that point in the flight has a thrust to weight ratio of less than one — the main engines actually have insufficient thrust to exceed the force of gravity, and the vertical speed given to it by the SRBs temporarily decreases.

NBA Sixth Man Award. The Shuttle then begins accelerating to orbit on the Space Shuttle Main Engines. NBA Most Improved Player Award. The SRBs parachute back to the ocean to be reused. NBA Most Valuable Player Award, NBA Finals MVP Award. 126 seconds after launch, explosive bolts release the SRBs and small separation rockets push them laterally away from the vehicle. List of Current NBA Team Rosters. Around a point called "max-q", where the aerodynamic forces are at their maximum, the main engines are temporarily throttled back to avoid overspeeding and hence overstressing the Shuttle (particularly vulnerable parts such as the wings).

List of NBA players. Orbital velocity at the 380 km (236 miles) altitude of the International Space Station is 7.68 km per second, or 17,180 mph, roughly equivalent to Mach 23. David Stern, Commissioner since 1984. This isn't visually obvious since the vehicle rises vertically and is out of sight for most of the horizontal acceleration. Larry O'Brien, Commissioner from 1975 to 1984. To achieve orbit requires expending much more energy in a horizontal direction than in a vertical direction. Walter Kennedy, President from 1963 to 1967 and Commissioner from 1967 to 1975. The vehicle climbs in a progressively flattening arc, accelerating as the weight of the SRBs and main tank decrease.

Maurice Podoloff, President from 1946 to 1963. Shortly after clearing the tower the Shuttle rotates so that the vehicle is below the external tank and SRBs. Basketball Hall of Fame. At takeoff the vast majority (~71%) of the thrust is provided by the SRBs. Waterloo Hawks (1949–1950). After the Challenger disaster, there were extensive upgrades to abort modes. Washington Capitols (1946–1951). Many of these concern SSME failures, since that is the most complex and highly stressed component.

Toronto Huskies (1946–1947). There are extensive emergency procedures (abort modes) to handle various failure scenarios during ascent. Sheboygan Redskins (1949–1950). The SRBs cannot be turned off once ignited, and afterwards the shuttle must take off, no matter what. Louis Bombers (1946–1950). Initially the main engines are ignited and computers verify their operation for several seconds; if successful, the SRBs are ignited and the vehicle is then committed to takeoff. St. It is called the Shuttle-C and would trade re-usability for cargo capability with large potential savings from reusing technology developed for the Space Shuttle.

Providence Steamrollers (1946–1949). A cargo-only, unmanned variant of the Shuttle has been variously proposed and rejected since the 1980s. Pittsburgh Ironmen (1946–1947). In addition the Air Force developed their own much lighter single-piece SRB design using a filament-wound system, but this too was cancelled. Indianapolis Olympians (1949–1953). The loss of the ASRB program forced the development of the Super LightWeight external Tank (SLWT), which provides some of the increased payload capability, while not providing any of the safety improvements. Indianapolis Jets (1948–1949). These culminated in the considerably simpler, lower cost, probably safer and better performing Advanced Solid Rocket Booster which was to have entered production in the early to mid-1990s to support the Space Station, but was later cancelled to save money after the expenditure of $2.2 billion.

Detroit Gems (1949–1950). Several other SRB improvements were planned in order to improve performance and safety, but never came to be. Detroit Falcons (1946–1947). Notable is the adding of a third O-ring seal to the joints between the segments, which occurred after the Challenger accident. Denver Nuggets (original) (1949–1950). The SRBs (Solid Rocket Boosters) have undergone improvements as well. Cleveland Rebels (1946–1947). As the Shuttle cannot fly unmanned, each of these improvements has been "tested" on operational flights.

Chicago Stags (1946–1950). It weighs 7,500 lb (3.4 t) less than the last run of lightweight tanks. Baltimore Bullets (1947–1955: last NBA team to fold). This version of the tank is made of the 2195 Aluminum-Lithium alloy. Anderson Packers (1949–1950). STS-91 saw the first flight of the "super light-weight external tank". The resulting "light-weight external tank" has been used on the vast majority of Shuttle missions.

Additional weight was saved by removing some of the internal "stringers" in the hydrogen tank that proved unnecessary. The 600lbs saved by not painting the tank results in an almost 600lb increase in payload capability to orbit. For STS-1 and STS-2 the external tank was painted white to protect the insulation that covers much of the tank, but improvements and testing showed that it was not required. The normal maximum throttle is 104%, with 106% and 109% available for abort emergencies.

The 109% thrust level was finally reached in flight hardware with the Block II engines in 2001. The upgrades have improved engine reliability, maintainability and performance. SSME upgrades are denoted as "block numbers", such as block I, block II, and block IIA. However this would have required revising much previous documentation and software, so the 104% number was retained.

They could have rescaled the output number, saying in essence 104% is now 100%. During the lengthy development program, Rocketdyne determined the engine was capable of safe reliable operation at 104% of the originally specified thrust. The 100% figure is the original specified power level. This explains phrases such as "Main engines throttling up to 104%." This does not mean the engines are being run over a safe limit.

The Space Shuttle Main Engines have had several improvements to enhance reliability and power. With the coming of the Space Station, the Orbiter's internal airlocks are being replaced with external docking systems to allow for a greater amount of cargo to be stored on the Shuttle's mid-deck during Station resupply missions. In the Apollo-Soyuz Test Project tradition, programmable calculators are carried as well (originally the HP-41C). This is called a "glass cockpit".

In addition to the computer upgrades, the original vector graphics monochrome cockpit displays were replaced with modern raster color displays, similar to contemporary airliners like the Airbus A320. Internally the Shuttle remains largely similar to the original design, with the exception of the improved avionics computers. The memory was changed from magnetic core to semiconductor with battery backup. In 1990 the original computers were replaced with an upgraded model AP-101S, which has about 2.5 times the memory capacity (about 1 megabyte) and three times the processor speed (about 1.2 million instructions per second).

They have no hard disk drive, but load software from tape cartridges. The CPU could process about 400,000 instructions per second. The IBM AP-101 computers originally had about 424 kilobytes of magnetic core memory each. It is specifically designed for a real time embedded system environment.

The software for the shuttle computers are written in a high-level language called HAL/S, somewhat similar to PL/I. However in theory it can fail, so the BFS exists for that contingency. For example the number of code lines is tiny relative to a commercial operating system, changes are only made infrequently and with extensive testing, and many programming and test personnel work on the small amount of computer code. This should never happen, as embedded system avionic software is developed under totally different conditions than commercial software.

The BFS was created because although the four primary computers are hardware redundant, they all run the same software, so a generic software problem could crash all of them. The Backup Flight System (BFS) is separately developed software running on the fifth computer, used only if the entire four-computer primary system fails. In the rare case of two out of four computers simultaneously failing (a two-two split), one group is picked at random. If a second computer of the three remaining fails, the two functioning computers vote it out.

This isolates it from vehicle control. If one computer fails the three functioning computers "vote" it out of the system. The four general purpose computers operate essentially in lockstep, checking each other. After two failures it can land safely.

After a single failure the shuttle can continue the mission. The design goal of the shuttle DPS is fail operational/fail safe reliability. Collectively they are called the shuttle Data Processing System (DPS). A fifth backup computer runs separate software called the Backup Flight System (BFS).

Four computers run specialized software called the Primary Avionics Software System (PASS). The shuttle uses five identical redundant IBM 32-bit general purpose computers (GPCs), model AP-101, constituting a type of embedded system. Much research went into the shuttle computer system. A primary concern with digital fly-by-wire systems is reliability.

This means no mechanical or hydraulic linkages connect the pilot's control stick to the control surfaces or reaction control system thrusters. The shuttle was one of the earliest aircraft to use a computerized fly-by-wire digital flight control system. The SRB cases are made of steel about 1/2 inch (1.27 cm) thick. They are jettisoned two minutes after launch at a height of 36 nautical miles (67 km), then deploy parachutes and land in the ocean to be recovered.

The Solid Rocket Boosters (SRBs) contain the solid fuel that provides about 71% of the vehicle's liftoff thrust. The ET is made of aluminum-lithium alloy. It is discarded 8.5 minutes after launch at an altitude of 60 nautical miles (111 km) then burns up on reentry. The External Tank (ET) contains the 2 million liters (528,000 gallons) of liquid hydrogen and liquid oxygen propellant that feeds the SSMEs.

The orbiter structure is made primarily from aluminum alloy, although the engine thrust structure is made from titanium. Unlike previous space vehicles which used insulation that burned off during reentry and couldn't be reused, the orbiter thermal protection can be reused up to 100 times with only minor repairs. Lower temperature areas on the upper surfaces are protected by flexible thermal blankets. The underbelly and much of the fuselage sides is protected by silica tiles.

The hottest areas are on the wing leading edges and nose, which are protected by reinforced carbon/carbon. Various materials are used, depending on the amount of heat. The Thermal Protection System (TPS) covers the outside of the obiter, protecting it from the intense heat during reentry. The Reaction Control System (RCS) provides attitude control and translation along the pitch, roll, and yaw axes during the flight phases of orbit insertion, orbit, and reentry.

The Orbital Maneuvering System (OMS) provides orbital maneuvers, including insertion, circularization, transfer, rendezvous, abort to orbit, and abort once around. They are used for propulsion during ascent. Three Space Shuttle Main Engines (SSMEs) are mounted in the rear part of the obiter. Since the arm is a crucial part of the Thermal Protection Inspection procedures now required for Shuttle flights, it will probably be included on all future flights.

Until the loss of Columbia, the Canadarm had been used only on those missions where it was needed. Inside the payload bay is the Remote Manipulator System, also known as the Canadarm, a robot arm used to retrieve and deploy payloads. Thermal control is also maintained by adjusting the orientation of the Shuttle relative to Earth and Sun. The payload bay doors have heat radiators mounted on their inner surfaces, and so are kept open for thermal control while the Shuttle is in orbit.

The orbiter has a large 60 by 15 ft (18  m by 4.6 m) payload bay, filling most of the fuselage. Astronauts pass through the airlock hatch to put on their space suits. Galley, toilet, sleep locations, storage lockers, and the side hatch for entering/exiting the vehicle is also located there, as is the airlock hatch into the payload bay. The mid-deck has three more seats for the rest of the crew members.

The highest flight deck seats the commander and pilot, two mission specialists in the back. Its crew cabin consists of three levels: the flight deck, the mid-deck, and the utility area. The orbiter resembles an airplane with delta wings. The vehicle is launched vertically like a conventional rocket, and the orbiter glides to a horizontal landing like an airplane, after which it is refurbished for reuse.

The tank and boosters are jettisoned during ascent, so only the orbiter goes into orbit. The shuttle is a partially reusuable launch system composed of three main assemblies: the reusable Orbiter Vehicle (OV), the expendable External Tank (ET), and the two reusable Solid Rocket Boosters (SRBs). Columbia was lost, with all seven crew members, during reentry on February 1, 2003, and has not been replaced. Endeavour was built to replace it (using spare parts originally intended for the other Orbiters) and delivered in May 1991.

Challenger was destroyed when she disintegrated during launch on January 28, 1986, with the loss of all seven astronauts on board. The Shuttle was meant to visit Space Station Freedom, announced in 1984, an ambitious and much-delayed project later downsized and merged into the International Space Station program. Challenger was delivered to KSC in July 1982, Discovery was delivered in November 1983, and Atlantis was delivered in April 1985. The first fully functional Shuttle Orbiter, built in Palmdale, California, was the Columbia, which was delivered to Kennedy Space Center on March 25, 1979, and was first launched on April 12, 1981—the 20th anniversary of Yuri Gagarin's space flight—with a crew of two.

Amid great fanfare, the Enterprise was rolled out on September 17, 1976, and later conducted a successful series of glide-approach and landing tests that were the first real validation of the design. The first complete Orbiter was originally named Constitution, but a massive write-in campaign from fans of the Star Trek television series convinced the White House to change the name to Enterprise. The contractor for the Space Shuttle Solid Rocket Boosters was Morton Thiokol (now part of Alliant Techsystems), for the external tank, Martin Marietta (now Lockheed Martin), and for the Space shuttle main engines, Rocketdyne. The prime contractor for the program was North American Aviation (later Rockwell International), the same company responsible for the Apollo Command/Service Module.

The final design was less costly and less technically ambitious than earlier fully reusable designs. The Shuttle program was formally launched on January 5, 1972, when President Nixon announced that NASA would proceed with the development of a reusable Space Shuttle system. Ultimately the current design was chosen, using a reusable winged orbiter, solid rocket boosters, and expendable external tank. During early shuttle development there was great debate about the optimal shuttle design that best balanced capability, development cost and operating cost.

They evaluated the shuttle studies to date, and recommended a national space strategy including building a space shuttle. Agnew. Nixon formed the Space Task Group, chaired by vice president Spiro T. In 1969 President Richard M.

The early studies were denoted "Phase A", and in June 1970, "Phase B", which were more detailed and specific. Even before the Apollo moon landing in 1969, in October 1968 NASA began early studies of space shuttle designs. .
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However, following the STS-114 return-to-flight mission in August 2005, the Shuttle program is currently grounded pending repairs and the solution of outstanding safety issues. According to the Vision for Space Exploration, use of the Space Shuttle will be focused on completing assembly of the ISS in 2010, after which it will be replaced by the yet-to-be-developed Crew Exploration Vehicle (CEV). The program started in the late 1960s and has dominated NASA's manned operations since the mid-1970s. Each Shuttle was designed for a projected lifespan of 100 launches or 10-years operational life.

However this cabability is used to return large payloads to earth from the International Space Station, as the Russian Soyuz has limited capacity for return payloads. While the vehicle was designed with the capability to recover satellites and other payloads from orbit and return them to Earth, this capacity has not been used often. It carries large payloads to various orbits, provides crew rotation for the International Space Station (ISS), and performs servicing missions. It is also the first winged manned spacecraft to achieve orbit and land.

The Shuttle is the first orbital spacecraft designed for partial reusability. When its mission is complete, it re-enters the earth's atmosphere and makes an unpowered gliding horizontal landing, usually on a runway at Kennedy Space Center. The winged shuttle orbiter is launched vertically, carrying usually five to seven astronauts and up to about 22,700 kg (50,000 lbs) of payload into low earth orbit. NASA's Space Shuttle, officially called Space Transportation System (STS), is the United States government's sole manned launch vehicle currently in service.

The trailer allows the transportation of the Orbiter from the OPF to either the SCA-747 "Mate-Demate" stand or the VAB without placing any additional stress on the undercarriage. Prior to the closing of the Vandenburg facility, Orbiters were transported from the OPF to the VAB on its undercarriage, only to be raised when the Orbiter was being lifted for attachment to the SRB/ET stack. Air Force's launch facility at Vandenburg Air Force Base in California (since then converted for Delta V rockets) that would transport the Orbiter from the landing facility to the launch pad, which allowed both "stacking" and launch without utilizing a separate VAB-style building and crawler-transporter roadway. A 36-wheeled transport trailer, originally built for the U.S.

The Shuttle Carrier Aircraft is a modified Boeing 747 that flies the Space Shuttle from alternative landing sites back to Cape Canaveral. The Crawler-Transporter moves the Space Shuttle from the Vehicle Assembly Building to Launch Complex 39. While the shuttle might safely endure a lightning strike, a similar strike caused problems on Apollo 14, so for improved safety NASA chooses to not launch the shuttle if lightning is possible. However upon takeoff the shuttle sends out a long exhaust plume as it ascends, and this plume can trigger lightning, plus provide a current path to ground.

Like most jet airliners, the shuttle is constructed of conductive aluminum which would normally protect the internal systems. Airplanes are often struck by lightning with no adverse effects because the electricity of the strike is dissipated through the conductive structure and the aircraft is not electrically grounded. The shuttle is not launched under conditions where it could be struck by lightning. Since then, NASA has installed commercial plastic owl decoys and inflatable owl balloons which must be removed prior to launch.

One shuttle launch was delayed in 1995 when a pair of woodpeckers drilled almost 200 holes into the foam insulation of Discovery's external tank. When CNN reported on the breakup of the Columbia over Texas, they erroneously reported it was traveling at nearly 18 times the speed of light, instead of 18 times the speed of sound. (source : John Young's April 2003 After Dinner Speech). On the same subject, a little-publicised detail about the first Shuttle mission, STS-1, was that it had a protruding gapfiller that ducted hot gas into the right wheel well on re-entry, buckling the right main gear on landing as a result.

This image from the NASA archives shows many missing tiles on the STS-1 OMS pods : [[5]] The problem on Columbia was that the damage was sustained to the carbon-carbon leading edge panel of the wing, not the heat tiles. STS-1, STS-16 and STS-41 have all flown with missing thermal tiles from the orbital maneuvering system pods (visible to all the crew). In fact Shuttles had come back missing as many as 20 tiles without any problem. The subject of missing or damaged thermal tiles on the Shuttle fleet only became an issue following the loss of Columbia in 2003 as it broke up on re-entry.

At the point when it is perfectly vertical, the boosters ignite and the launch commences. This takes approximately 6 seconds. As the boosters flex back into their original shape, the launch stack springs slowly back upright. After main engine start, but while the solid rocket boosters are still clamped to the pad, the offset thrust from the Shuttle's three main engines causes the entire launch stack (boosters, tank and shuttle) to flex forwards about 2 meters at the cockpit level.

When watching a launch, look for the "nod" ("Twang" in "NASAese"). NASA was one of its main customers. The Compass sold poorly, because it cost at least $8000, but offered unmatched performance for its weight and size. Early Shuttle missions took along the GRiD Compass, arguably the first laptop computer.

This is still lower than the actual approximately $100 million per launch, but less difference than is commonly thought. Correcting for inflation to 2005 dollars, this equates roughly to $36 million incremental costs per launch. Early cost estimates of $118 per pound of payload were based on marginal or incremental launch costs, and based on 1972 dollars and assuming a 65,000 pound payload capacity. Some early hypothetical studies examined 55 launches per year, but the maximum possible launch rate was limited to 24 per year, based on manufacturing capacity of the external tank.

This does not reduce actual operating costs, but if dividing total program costs by number of launches, more launches per year produces a lower per-launch cost figure. Launch rate is significantly lower than initially expected. Before the current "Block II" engines, the turbopumps (a primary engine component) had to be removed, dissembled, and totally overhauled after each flight. The main engines were highly complex and maintenance intensive, necessitating removal and extensive inspection after each flight.

Maintenance of thermal protection tiles turned out to be very labor intensive, averaging about 1 person·week to replace a tile, with hundreds damaged with each launch. Columbia — lost during reentry, February 1, 2003. Challenger — lost 73 seconds after liftoff, January 28, 1986. Ulysses probe.

Galileo spacecraft. Magellan probe. An interplanetary orbit; these have included: