Intelsat 603 rescue

[nanochickin]

Came across this little bit of info about the rescue of Intelsat 603, The third of five Intelsat-VI satellites

Its now probably very near to the end of its operational life and is operating @ 20°W on a 4.3° inclined orbit, mostly broadcasting S-I-S horse racing feeds

It was launched on 14-03-1990 on top of a Titan-3 rocket. Unfortunately the second stage of the rocket failed to separate from the satellite due to faulty wiring between the rocket and the satellite. This left the satellite in an orbit too low and too unstable for it to be of any use.

Basically it was decided to rescue the satellite rather than de-orbiting it. This was sucessful which left 603 operating at its proper position, 23,500 miles above the equator @ 24.5° west in geosynchronous orbit

One of its first broadcasts was the 1992 Summer Olympics in Barcelona which was broadcast to television stations all over the world

Below is a picture of the satellite being rescued



The full story can be found @ _http://uu.cx/flight/49/



Nano

[nanochickin]

Incidently its 4 sister satellites 601 -> 605 are mostly still operational with only 604 no longer in service after being put into junk orbit during March 2006 I don't think it will be long before its joined by its other sisters

Intelsat 601 -> Co-located with Intelsat 906 (from what Analogsat tells me) @ 64°E. Not Broadcasting.
Intelsat 602 -> Parked at 150.5°E at a 4.8° Inclination - Not broadcasting anything at the moment.
Intelsat 604 -> In Junk Orbit - Last slotted in @ 177.85°E, 4° inclined until being Junked Mar 2006
Intelsat 605 -> Parked at 174°e on a 2.3° inclination - Not broadcasting anything at the moment.

In early Sep 1997 605 satellite experienced an "anomaly" with telemetry. The telemetry problem affected the attitude control and the satellite was not reporting its location to ground control anymore. Therefore the position had to be computed by ground stations (by measuring signal strength).

Those telemetry problems were eventualy solved in Dec 1997 so that the satellite could resume normal operations.

[BGonaSTICK]

Very interesting

[nanochickin]

Theres some more stuff about the Intelsat VI spacecraft at the urls below

_http://space.skyrocket.de/index_frame.htm?http://space.skyrocket.de/doc_sdat/intelsat-6.htm

_http://www.geo-orbit.org/easthemipgs/intel6spec.html

The main site covers vertually every satellite launch since 1960.

_http://space.skyrocket.de/

Quite a good read if your into that sort of thing




Nano

[madrat]

What is an inclined orbit :?

[satsid]

Originally Posted by madrat

What is an inclined orbit :?

inclined orbit is a satellite thats running out of fule,so drifts in the sky a bit.If you looking @ a inclined satellite its not 100% where it says it is.Some guys use a jack to lift there dish up or down to view a inclined orbit satellite.
sid

[Analoguesat]

Originally Posted by madrat

What is an inclined orbit :?

When a geostationary satekllite runs short of station keeping fuel the operators can get another 2-4 years use out of by letting it run inclined. This means the north - south station keeping corrections are no longer done so the satellite begins to wobble north-south off the geostationary arc in an elongated figure of 8 due to gravitational effects.

To begin with the end user will not notice any difference, however once the inclination passes 1 degree the satellite will start running outside the usable acceptance angle of home & hobby dishes for longer and longer periods every day. At this point the sat is useless for home reception so it is then used for short term news feeds or cheap short term leases for operators who can cope with the wobble.

The wobble will increase by about 1 degree a year, and once the inclination gets up past 4 degrees the satellite will be retired to junk orbit. The motors are fired for the last time to get it a few dozen miles off the main orbital arc and out of the way. The last dregs of fuel are vented to space to stop any accidental explosions, the final commands are uplinked onto the bird to shut the final systems down, the batteries are shorted out and the old bird is then dead, abandoned to drift for ever more

[Yorks]

Originally Posted by Analoguesat

the final commands are uplinked onto the bird to shut the final systems down, the batteries are shorted out and the old bird is then dead, abandoned to drift for ever more

The satellite then drifts several light years until it reaches another galaxy, where it is rescued by an intellegent life form. It is then repaired and reborn to be enjoyed by millions more........... and the cycle goes on.

Sorry A.- but I can't stand a sad ending

[madrat]

Didn't one of the old Astra satellites have a wobble?

Pity they don't send the old Sat's to burn up in earths atmosphere, could make for some brilliant light shows :clap:

[Analoguesat]

Some old satellites are reorbited into the atmosphere - but they tend to be the ones in low earth orbit. Skylab burned up in the 1970's, MIR was crashed about 5 years agoAstra 1K was deorbited in December 2002 after a botched launch left it in a useless low orbit.

Most deorbits are over the Pacific for safety reasons - nothing to accidently land on if the deorbit misses its target by a few hundred miles! - so only a few deep sea fishermen tend to see them.