| Title: | Space Exploration |
| Notice: | Shuttle launch schedules, see Note 6 |
| Moderator: | PRAGMA::GRIFFIN |
| Created: | Mon Feb 17 1986 |
| Last Modified: | Thu Jun 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 974 |
| Total number of notes: | 18843 |
Associated Press Tue 10-SEP-1985 00:24 Satellite Fails
By PAUL RECER
AP Aerospace Writer
SPACE CENTER, Houston (AP) - Hughes Communications Inc.
engineers are working to restore the primary communications circuit
on a Navy satellite that was launched only days ago from space
shuttle Discovery.
The satellite, Syncom 4, was functioning normally during testing
when its primary UHF communications circuit suddenly failed, Hughes
spokeswoman Penelope Longbottom said Monday. ``The problem ...
developed after two days of normal testing. All efforts to revive
the UHF links have so far been unsuccessful.''
A team of experts is attempting to find the problem and restore
the circuit, but ``no conclusions have yet been reached,'' she said.
The $85 million Syncom 4 was deployed Aug. 29 in a low orbit
from Discovery. It later rocketed itself into geostationary orbit
22,300 miles above the Earth as planned.
The satellite is owned by Hughes and was to be leased to the
Navy as part of a four-craft network providing global military
communications.
Syncom 4, called Leasat 4 by the Navy, is a sister craft to
Syncom 3, the satellite that was repaired in orbit by two
spacewalking Discovery astronauts. Ms. Longbottom said the revived
Syncom 3 appears to be in good condition.
Syncom 3 was left lifeless in orbit for four months after it
experienced a problem last April, just after its launch. Discovery
astronauts Bill Fisher and James van Hoften installed electronic
boxes on the satellite to enable Hughes engineers to command it
from the ground.
The Hughes engineers have since allowed Syncom 3 to slowly warm
up. Plans call for the craft to rocket itself into a high orbit
Oct. 29.
Two other satellites in the Navy communications network are on
station and working properly, said Ms. Longbottom. Syncom 1 was
launched in August 1984 and Syncom 2 three months later.
Ms. Longbottom said that if Syncom 4 cannot be revived, Hughes
has a spare satellite that can be launched to complete the military
communications network.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 78.1 | PYRITE::WEAVER | Tue Sep 17 1985 13:12 | 47 | ||
Associated Press Tue 17-SEP-1985 07:32 Dead Satellite
By ROGER GILLOTT
AP Business Writer
LOS ANGELES (AP) - An $84 million satellite put into orbit by
the crew of space shuttle Discovery does not respond to radio
signals and is considered to be a total loss, Hughes Communications
Inc. says.
``It is doubtful that continuing efforts to revive the
communications payload will be successful,'' said Hughes, whose
engineers have been trying to revive Syncom 4 since the problem
cropped up days after its Aug. 29 launch.
Hughes didn't disclose the problem until last week.
Hughes said Monday it considers the satellite a total loss and
will file a claim with its insurers for the full $84 million value.
Spokeswoman Elizabeth Hess said names of the insurers were not
immediately available.
There is no chance of rescuing the satellite, which reached its
assigned orbit 22,300 miles above the Earth, where it remains
stationary relative to the ground, and is far beyond the reach of
the space shuttle.
Although the satellite has small rockets used to keep it on
station, it does not have the fuel to return to an orbit where the
shuttle could reach it, Hughes said.
The satellite reached its assigned position on Sept. 3, and
``functioned normally for about two days,'' the company said. At
that point, the satellite stopped relaying transmissions back to
Earth.
The most probable cause of the lost signal, according to Hughes,
lies in the failure of a cable linking the satellite's transmitter
to its antennas.
Syncom 4, known as Leasat 4 by the Navy, was to be part of a
four-craft network providing global communications for the U.S.
Navy.
Another satellite, Syncom 5, will be launched from the next
shuttle flight to complete the network, Hughes said.
A sister satellite, Syncom 3, went dead in orbit after being
launched last April and remained lifeless for four months until it
was jump-started by spacewalking astronauts Bill Fisher and James
van Hoften last month.
There had been concern that Syncom 3 might have been idle for so
long it had frozen and might not be able to be restarted. But the
company said Monday that it had been sufficiently warmed up and is
to rocket itself into a higher orbit Oct. 29.
The other two satellites in the network are doing well,
officials said. Syncom 1 was sent aloft in August 1984 and Syncom 2
three months later.
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