An artist's concept of what TDRS-H will look like once full deployed in space. Photo: Hughes

NASA's newest tracking and communications spacecraft is sailing smoothly through a series of critical maneuvers to achieve its orbital perch above Earth, an official said Thursday.

The Tracking and Data Relay Satellite-H, or TDRS-H, was launched into space last Friday aboard a Lockheed Martin Atlas 2A rocket from Cape Canaveral Air Force Station, Florida.

Since then the craft has been guided by personnel at Hughes Space and Communications' mission control center. Hughes built the satellite for NASA.

Within an hour of its thunderous liftoff, ground controllers established contact with the satellite, beginning a sequence of events that will deliver TDRS-H into geostationary orbit about 22,300 miles above the equator this weekend.

The Atlas rocket placed the satellite into a highly elliptical geosynchronous transfer orbit. From there the craft's liquid-fueled onboard kick motor is responsible for raising and circularizing the orbit.

Several of the maneuvers have been performed in the last week, delivering the satellite into a current orbit with a high point of 22,376 miles, a low end of 12,621 miles and inclined less than 10 degrees to the equator.

Three more engine firings are planned -- one today around 10 a.m. EDT (1400 GMT); one on Saturday at about 7 a.m. EDT (1100 GMT) and a trim burn on Sunday at 3 a.m. EDT (0700 GMT).

"There are always some tense periods when you are orbit raising," said Robert Jenkens, Jr., NASA's TDRS deputy project manager. "Knock on wood, it has been going very smoothly."

The Lockheed Maritn Atlas 2A rocket lifts off with TDRS-H on June 30. Photo: NASA/KSC

The final maneuver Sunday will set TDRS-H into its orbital slot at 150 degrees West longitude, seemingly fixed over one spot of the globe, to begin several months of testing and checkout.

On Monday and Tuesday plans call for the satellite's twin power-generating solar arrays and booms holding the two 15-foot diameter antenna reflectors to be deployed.

Also next week, control of TDRS-H will be handed from the Hughes center to NASA's White Sands complex in New Mexico. White Sands is where the western flank of the TDRS constellation controlled.

NASA currently operates a fleet of six other TDRS satellites, all launched aboard space shuttles from 1983 through 1995.

The TDRS system is NASA's preeminent means of relaying television, data and science information from space shuttles, the Hubble Space Telescope and a host of other robotic space missions. In the future the International Space Station will rely heavily on TDRS satellites.

TDRS-H is the first of three advanced satellites to be launched to keep the constellation operating for the next 15 years. The new craft offer increased bandwidth and greater tuning flexibility for relaying science data and clear pictures from space.

Upon the completion of testing, the new satellite -- to be renamed TDRS-8 -- will be positioned at 171 degrees West longitude to orbit alongside TDRS-7.