Columbia goes to work

Space shuttle Columbia's fifth space flight - called STS-5 - lifted off from Florida's Kennedy Space Center exactly on schedule at 7:19 a.m. Thursday. With all systems performing with precision, the first four-member Space Transportation System (STS) crew had little to say and no complaints as the reusable shuttle climbed neatly into its 185-mile high orbit.

Plans are to put two $30-million commercial satellites into orbit Thursday and Friday afternoons, and then the crew plans to add a space walk Sunday to other shuttle achievements. Landing is scheduled for California on Tuesday morning.

STS-5 is billed as the $15 billion shuttle program's ''first operational flight'' because Columbia is carrying its first paying cargo after successfully completing four orbital test missions. But the current flight may be the greatest test of all.

With the technical challenges of launch, orbit, reentry, and landing transformed by past flights into computer-precise routine, the STS-5 becomes a major test of profitability and reliability. Business interests around the world are watching closely to check on the investments made by Canada's Telesat system and by Satellite Business Systems (a joint venture backed by Aetna Life & Casualty Company, Communications Satellite Corporation, and International Business Machines Corporation). The two groups are paying $9 million each to put two satellites into stable 22,300-mile orbits.

The $18 million bill for placing the two satellites in orbit covers roughly half of this flight's expenses. National Aeronautics and Space Administration (NASA) officials hope their bargain prices will attract enough customers for future flights to turn their space-trucking service into a profitmaking operation.

The STS-5 also puts two ''mission specialists'' to work for the first time. After 15 years of training and waiting, Joseph P. Allen and William B. Lenoir are finally in orbit. They are to don pressure suits Sunday to carry out the first ''extravehicular activity'' since 1974. In a 31/2-hour work period, they will test their ability to maneuver and perform mechanical tasks in the open cargo bay. STS-5 commander Vance D. Brand and pilot Robert F. Overmyer will watch this space walk from shirt-sleeved comfort inside the craft.

Mission plans call for Drs. Allen and Lenoir to test procedures for repairing damaged satellites. But they have been trained to handle any difficulties that might develop with Columbia's two satellites. This offers the shuttle's commercial customers an important extra guarantee that their equipment will be placed in orbit successfully, ready to begin the money-spinning work of relaying telephone and television transmissions.

But potential commercial users will be counting costs carefully. Early studies of the reusable shuttle concept estimated that a profitable and reliable service would require a stable of five orbiters making 55 flights a year. Subsequent fine-tuning has put the break-even point at perhaps 30 flights a year. But a tight Reagan administration rein on NASA's budget is holding the program to 24 flights a year, after canceling plans for a fifth orbiter.

A further concern for potential customers is that under current procedures the US Defense Department can ''bump'' any scheduled commercial cargo. The failure of a secret military experiment carried by the June 27-July 4 STS-4 flight raises concern that this troublesome, bulky payload may be sent aloft again, perhaps causing serious problems for a commercial customer bumped after a long wait.

One hope shared by the European Space Agency and the private Space Services of America is that their ground-launched, single-use rockets will attract customers willing to pay a higher price in return for a guaranteed schedule for placing satellites in orbit.