The first orbital flight of the space shuttle is set for March 14, 1981 -- nearly three years later than expected when the program was begun in 1972. But the technological spinoff from the shuttle project is already well under way.
Americans will likely see the greatest impact from the new space venture in the years ahead, points out Joseph P. Loftus, chief of technical planning at the Lyndon B. Johnson Space Center here. That is when scientists and specialists from private industry may develop products and processes in orbit, not now feasible within the influence of Earth's gravity. The shuttle will transport men and materials into orbit and then glide back to earth for re-use.
However, innovative technology and new materials developed in building the shuttle, which has features of both an airplane and a space ship, already are finding mundane commercial application in the United States.
Mr. Loftus likens the spread of space technology to dropping a rock in a pond. In developing the shuttle, scientists found solutions to design and engineering problems that now are slowly rippling into the private sector. "That process is probably near its peak right now," Loftus says.
Here are a few examples of shuttle-related technology with both proved and potential application for society as a whole:
* The silica tiles that delayed the launch of the shuttle because they kept popping off the vehicle have great potential as a liner for industrial furnaces, says Loftus. The material is being used on the exterior of the shuttle to insulate the vehicle from the tremendous heat it will encounter on reentering the Earth's atmosphere. Although it is expensive, silica could make a good furnace liner in the manufacture of precision parts like ceramic jet-engine components, says Loftus.
* A fire-resistant "polymide resiliant foam" developed for the shuttle will be produced commercially in 1981. It is expected to have wide application for airlines, subways, school buses, trains as a material for seat cushions. NASA (National Aeronautics and Space Administration) officials see it as a good substitute for polyurethane, which gives off toxic fumes when ignited. The new foam is also lighter than current products on the market.
* In designing the sophisticated electronic systems for the space shuttle, NASA scientists developed a slide-rule-like calculator that can determine more precisely and quickly what wire gauge is best for a particular electrical job. Loftus says a small company in Chicago has begun manufacturing the calculator for commercial distribution.
* The complexity of the shuttle's electronic wiring system also required NASA engineers to develop a better way of stripping insulation from wire -- a process that, when done mechanically, can nick and easily damage the wire.
NASA developed devices that cut the insulation with a laser beam. The beam vaporizes the insulation, but it merely reflects off the underlying metal. The process is expensive, but it can be cost-effective when it is essential that the wire not be damaged. Loftus says this device has gained some commercial use.
In broader terms, two of the most signifcant achievements of the shuttle program have been the development of an engine that operates at higher temperatures and pressures than anything used in previous space programs, and the development of quad-redundant control systems.
Redundancy means providing a backup to any functioning system in case of failure or malfunction. However, the performance demands on the shuttle are so great that the system has been made quad-redundant, meaning there are two more layers of backup for any failure in the operation of the vehicle. This feature could be incorporated into commercial aircraft and nuclear reactors to enhance their safety, Loftus says.