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To: Libloather

These are the guys American astronauts are going to be hitching a ride into space with. Yikes!


3 posted on 08/19/2011 9:26:47 PM PDT by FlingWingFlyer (Americans need to wean their government off of its dependence on foreign money.)
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To: FlingWingFlyer

Hitchin a ride that we are paying to the Russions upwards of $50 million per astronaut for. This is after laying off thousands of American workers.


4 posted on 08/19/2011 9:31:50 PM PDT by Captain7seas (FIRE JANE LUBCHENCO FROM NOAA)
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To: FlingWingFlyer

American industry has had failed satellite launches and failed birds as well.

Poop happens. Most “poop” in the satellite industry happens between launch and stabilization in geosynch orbit. There’s lots of stuff that has to go correctly to get the bird into final orbit:

1. Launch.
2. Get to geosync transfer orbit, which is an elliptic orbit.
3. Fire the AKM (apogee kick motor) to circularize the orbit.
4. Perform station keeping thrusting to finalize the ‘parking’ of the bird into the desired ‘slot’.

I got a taste of what can go wrong when I interned for RCA in the 80’s. We had a replacement bird that had been launched a few months prior, was allowed to ‘settle’ a bit, and it was drifting just out of it’s station. The spacecraft analysts performed a stationkeeping thrust burn to knock it east/south in the “box” and poof! The telemetry disappeared. Just freakin’ disappeared. Poof.

You should have seen how ashen people’s faces got. Back then, it was insured too... but there was only one underwriter and they were going to have a problem eating the entire loss. The insurance company would have had to pay out on not only the satellite, but also on 10 years’ of expected revenue... as the bird’s transponders were already sold going forward for at least 5 years, and there was a backlog of traffic coming online.

We had to go to raw audio from the radios (most all telemetry has a lot of computers and processing between the radio and what you see on the screen) to hear the thin, faded signal from the bird cycle across the receiver every 90 seconds or so... we had no idea what was going on. We were pretty sure it didn’t blow up because we were still hearing *something* on the specific frequency at that specific point in space... but the burn was so regular, so mundane, we couldn’t fathom what the heck happened.

After three days of intense orbital mechanics computations and telemetry sleuthing (which required copying signals on paper with a stopwatch and hand-decoding the data), the engineering team determined that the bird was tumbling end-over-end, and that one of the solar arrays had folded up.

Long story short, controllers loaded commands into the radios by hand, did a quick series of burns to stop the tumbling, re-orient the bird so we had the main antennas pointed back at earth and then set about finding out “WTF happened?!”

Turns out that after the AKM fired to put the bird into orbit, both the main gyro and the backup gyro were both spun up. The bird was in a meta-stable configuration... and all it needed was a little shove and suddenly the gyroscopic forces from having an extra gyro spun up made the bird go into a tumbling motion far faster than designers had though possible - which was why the solar array folded in on itself.

Poop happens. Poop that happens on satellite launches... well, it’s expensive.


13 posted on 08/19/2011 9:58:21 PM PDT by NVDave
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To: FlingWingFlyer

>>> These are the guys American astronauts are going to be hitching a ride into space with. Yikes!

Lucky we have Challenger and Columbia.


26 posted on 08/20/2011 1:17:07 AM PDT by tlb
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