Shuttle set to try to retrieve two satellites

Launch controllers at the Kennedy Space Center are counting down for a critical shuttle mission. Its success is important for building customer confidence in the United States Space Transportation System (STS) as a provider of effective and efficient service.

At this writing, the shuttle Discovery, with a five-astronaut crew, was scheduled to blast off on its second orbital flight at 8:18 a.m. Eastern standard time (EST) on Nov. 7. It would then be due to land at the center at 7: 57 a.m. EST on Nov. 15.

There are two crucial aspects to this eight-day mission, which is listed as 51-A on the National Aeronautics and Space Administration (NASA) STS manifest. These are to demonstrate the ability to carry out one of the most complex orbital assignments yet undertaken and, simply, to show that the STS team can launch this new mission within less than a month of the landing of the shuttle Challenger.

Shuttle commander Frederick H. Hauck and his crew have to launch two communications satellites. Then they are to retrieve Palapa B-2 and Westar 6. These communications satellites entered useless orbits when faulty nozzles caused their payload assist module (PAM) booster rockets to fail after the satellites were deployed during shuttle Mission 10 last February. One of the two satellites to be deployed this time also carries a PAM booster. Eight of these units have been successfully fired since the February failures.

Success of this aspect of the 51-A mission would help demonstrate that the STS team can both correct a critical defect - the PAM nozzle problem - in timely fashion and can recover ''lost'' satellites for refurbishment and reuse.

Indeed, this would be the first time orbiting satellites have been brought back to Earth - a capability that NASA would like to dramatize as an important option in its STS service.

But first, the STS team has to demonstrate that it can get Mission 51-A into orbit on schedule if it is to soften the skepticism with which its service is viewed by one of its most important customers, the US Department of Defense (DOD).

The shuttle Challenger, which returned from STS Mission 41-G on Oct. 13, is to undertake a secret DOD mission Dec. 8. If that mission is to get under way on time - demonstrating the rapid turnaround that NASA claims for the STS system - Discovery must lift off no later than Nov. 10. Every day's delay beyond that also delays the DOD mission because of launch pad preparation, according to Jesse W. Moore, NASA associate administrator for spaceflight.

NASA needs DOD's business if it is eventually to make STS service commercially viable. But DOD, which needs reliable on-time service, has expressed serious doubts about NASA's ability to provide it. Because of these doubts, the DOD now has authority to acquire expendable launch rockets to ensure that critical launches, such as those of communications or ''spy'' satellites, are not delayed.

NASA administrator James M. Beggs has said he considers this lack of DOD confidence and the potential loss of some DOD business a threat to the shuttle's viability. Thus NASA would like to launch Discovery smartly on Nov. 7, well ahead of the Nov. 10 deadline.