A crew of five military men flew the space shuttle Atlantis into orbit yesterday on a mission classified secret by the Defense Department.

It reportedly will put two new communications satellites into permanent positions above the equator.

Climbing away from Launch Pad 39A at Cape Canaveral at 11:15 a.m. EDT, four astronauts and one Air Force major took Atlantis on its maiden voyage into space on an easterly course that is the telltale sign of its destination.

That is an orbit that crosses the Earth at 28.5 degrees north and 28.5 degrees south of the equator. It is used whenever the shuttle's mission involves the deployment of communications satellites.

Yesterday's description of the last minutes of the countdown may be the last the public hears about Atlantis until it returns to Earth after completing its mission, whenever and whatever those are.

Even the 48-hour countdown to launch that ended yesterday morning at liftoff was secret.

The Department of Defense said only that Atlantis would be launched sometime between 10:20 a.m. and 1:20 p.m. and then yesterday the Pentagon added an hour to the launch period to make its launch time a bigger secret than it was on Wednesday.

The Defense Department will not identify Atlantis' destination, its mission or its stay-time in orbit.

The only thing it will say about landing is that it will occur at Edwards Air Force Base in California and that the media will be notified of landing time 24 hours before it occurs.

There is no public air-to-ground communications between Atlantis and the crew and the Mission Control Center in Houston.

Even the televised displays from mission control of the world map that shows the shuttle's position any time of day during a civilian mission have been deleted from this flight.

Atlantis' crew includes Air Force Col. Karol J. Bobko, Lt. Col. Ronald J. Grabe, Marine Corps Maj. David C. Hilmers, Army Col. Robert L. Stewart and Air Force Maj. William A. Pailes.

The first four are members of the National Aeronautics and Space Administration's astronaut corps, the last is an Air Force pilot assigned to this mission to assist in deploying its secret payload.