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The Evolving Space Shuttle: Upgrading to a Safer, Cheaper and More Capable Spacecraft

 Atlantis, top, returned to the Kennedy Space Center, FL, as the most modified Shuttle ever in September 1998. The updates include a new "glass cockpit," bottom, that replaced scores of outdated cockpit displays with new full-color flat panel screens.

Today's Space Shuttle, still less than one-quarter of the way through its design lifetime, is safer, more capable and less expensive to fly than ever before thanks to enhancements from new technologies incorporated into the original Shuttle design and improvements to the Shuttle's operation.

Since the first flight of Columbia in 1981, the Space Shuttle has launched more than 2 million pounds of cargo and over 500 passengers into orbit. The Shuttle continues to be the most reliable launch vehicle in the world, with unique capabilities that are unmatched. Each Space Shuttle orbiter was designed for 100 flights, yet the most completed so far are 25 each by Columbia and Discovery. Virtually all of the Shuttle's unique capabilities will be showcased in the varied flights planned in 1999: space station construction in orbit; launching the Chandra satellite observatory; mapping the Earth on the Shuttle Radar Topography Mission; and performing quick-turnaround satellite maintenance in orbit on the Hubble Space Telescope.

The flights this year will be capped by a space station construction mission that will launch what is now the most sophisticated Space Shuttle ever, Atlantis, fresh from an inspection and upgrade period that included more than 130 modifications. The updates to Atlantis include the most visibly apparent upgrade ever, the Multifunction Electronic Display Subsystem (MEDS), or “glass cockpit.” The glass cockpit consists of 11 full-color, flat-panel screens, nine in the forward cockpit and two in the aft cockpit, that replace almost three dozen outdated mechanical meters and gauges and four cathode-ray tube screens. The new system, similar to systems already common in commercial airliners, provides greater backup capabilities, weighs less and uses less power than the original displays. All Space Shuttles will be updated with the glass cockpit as they are periodically taken out of service for standard inspection periods, with updates to the entire fleet completed by 2002. Updates such as these need to continue to ensure that the U.S. is getting the most out of its investment and flying the safest and best Space Shuttle possible. Overall, since the early 1990s, highlights of achievements that have resulted from technical upgrades to the Space Shuttle and improvements to its operations include:

  • Since 1992, improvements to the Shuttle main engines have more than quadrupled estimates of their safety, and improvements throughout the Shuttle's systems have more than tripled estimates of the overall safety of the Shuttle.

  • Weight reductions in areas ranging from lighter seats in the crew cabin to a super lightweight external tank have been coupled with performance enhancements to increase the amount of cargo that can be carried to orbit by the Shuttle by more than 16,000 pounds.

  • The annual cost of operating the Space Shuttle has decreased by almost 40 percent when adjusted for inflation. About a $1.25 billion reduction has been realized in this year's budget as compared to the 1992 budget. In the next five years, costs are projected to decrease by hundreds of millions more dollars as operations continue to gain efficiency.

  • The amount of all in-flight problems on the Space Shuttle has decreased by 70 percent.

  • The precision and reliability of Shuttle launches have increased. The Shuttle has launched on time for 16 of the past 20 flights. On flights to the Mir and the International Space Station that have only minutes-long launch windows, the Shuttle launched on time for 16 consecutive missions, excluding delays caused by weather.

During the next ten years, continued upgrades that take advantage of new technologies are hoped to achieve long-range goals for the Space Shuttle that include: more than double the estimates of overall Shuttle safety from what they are today; provide the capability to accommodate as many as 15 flights a year; further reduce the time required to prepare a Shuttle for launch by almost two-thirds; further reduce the cost of launching a pound into orbit on the Shuttle to half of what it is today.

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 04/07/2002
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