Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SATURDAY, March 17, 1990 TAG: 9003172366
SECTION: NATIONAL/INTERNATIONAL PAGE: A2 EDITION: METRO
SOURCE: Associated Press
DATELINE: WASHINGTON LENGTH: Medium
Engineers were able to send the Intelsat VI satellite to a new, higher orbit, where it won't be drawn back to Earth by the thickening atmosphere.
The satellite failed to separate from its launch vehicle, a commercial Titan 3 rocket, after liftoff from Cape Canaveral on Wednesday and was trapped in a useless orbit that swung within 103 miles of Earth.
Friday, rocket builder Martin Marietta attributed the failure to a wiring problem in its Titan 3 launch vehicle that was "undetected by the processes and test procedures used in pre-launch checkout."
Kerry Masson, a Martin Marietta spokeswoman in Denver, said the signal failed to make it from an onboard computer to the mechanism that was to separate the rocket and the satellite.
Without that separation, a motor attached to the satellite was unable to propel the spacecraft to its duty station 22,300 miles above Earth. When engineers finally separated the sent rockets, the booster rocket remained with the launch vehicle and both were expected to fall back to Earth soon.
Intelsat, the international communications consortium which owns the $150 million uninsured satellite, fired small onboard thrusters and raised the satellite's orbit by nearly 60 miles. That put the 5-ton satellite out of immediate reach of the atmosphere.
Orbital Sciences Corp., a small Virginia aerospace company, sent a letter to various parties, including Intelsat and NASA, offering a newly developed rocket assembly that can be attached to a stranded satellite in orbit.
"Specifically, the OSC plan is to carry a replacement perigee motor to orbit on the shuttle, mate the motor to the satellite, and complete the mission from orbit rather than returning the satellite to Earth for refurbishment and relaunch," said the letter to NASA Administrator Richard Truly and others.
Only one transfer orbit stage has been built - the engineering model used in qualification tests.
While the satellite was in a 103 mile by 218 mile orbit, NASA said it would not consider a rescue. The low point of that orbit brushes the upper edge of the atmosphere and the satellite was given only a nine-day life.
In its new orbit, 161 miles at the low point, the Intelsat satellite can stay in space for months. Moreover, because the satellite had enough steering fuel to last for 13 years, there is plenty left to keep it out of the grip of the atmosphere.
by CNB