The space shuttle Atlantis landed safely yesterday with a promising cargo: videotapes to help design a U.S. space station, a purified hormone for tests of a new medical treatment and film that may locate hidden water in drought-ridden Africa.

With mission commander Brewster Shaw at the controls, the shuttle landed on a concrete runway at this desert base at 1:33 p.m. before 6,700 spectators.

Mission Control in Houston, Tex., had briefly considered delaying the landing because of clouds over Edwards. The space shuttle usually lands on a dry lake bed at Edwards rather than concrete, but nearly an inch of rain since Nov. 25 has left water in the lake bed.

The seven-member crew's 2.8 million-mile voyage started Nov. 26 with a night launch from the Kennedy Space Center in Florida.

During two spacewalks, astronauts Sherwood Spring and Jerry Ross built large structures of metal struts in the shuttle's open cargo bay.

Scientists believe that the demonstration will contribute to the design of a space station planned for the 1990s.

Atlantis also carried samples of a hormone that can be used to treat red-blood cell deficiencies, such as anemia.

The samples, purified in an electrical process that is more efficient in zero gravity, will be used in animal tests, the first step in winning Food and Drug Administration approval for clinical use.

The astronauts also launched three communications satellites.