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MHS
2002-Nov-24, 08:33 PM
As you might know the Space Shuttle launch of a few days ago was postponed because of the bad weather at the emergency landing site in Spain. If I remember correctly there has never been a Space Shuttle landing in Europe, but what about the rest of the world? Any recorded landings outside the US?

Colt
2002-Nov-24, 08:54 PM
I just realized that.. Why are they landing in Spain anyway? This could be due to orbital mechanics and lack of fuel but I doubt that. What a better place than Spain for some terrorist to blow up the shuttle.. -Colt

Firefox
2002-Nov-24, 09:03 PM
I would imagine it is because Spain is within close distance to the shuttle's trajectory, that if an emergency occurred after the spacecraft reached negative return (the point where the shuttle could not abort and return to KSC,) that they could land at designated airfields there. There are also similar sites in Africa, eastern Europe and throughout Asia. One site in northern Africa, in Morocco, has been shut down due to political unrest, IIRC.


-Adam

ToSeek
2002-Nov-24, 10:08 PM

ToSeek
2002-Nov-24, 10:08 PM
2002-11-24 16:03, Firefox wrote:
I would imagine it is because Spain is within close distance to the shuttle's trajectory, that if an emergency occurred after the spacecraft reached negative return (the point where the shuttle could not abort and return to KSC,) that they could land at designated airfields there. There are also similar sites in Africa, eastern Europe and throughout Asia. One site in northern Africa, in Morocco, has been shut down due to political unrest, IIRC.
-Adam


Exactly. There are certain shuttle failure scenarios where it's too far out to get back to Florida but doesn't have enough power to make it much beyond getting across the Atlantic. You'll hear calls during liftoff like "negative return" (meaning the shuttle can't come back to Kennedy), "two-engine TAL," meaning if you lose one engine you're into a Trans-Atlantic Landing (don't quote me on the acronym), and eventually "single engine press to MECO," which means you're going into orbit (Main Engine CutOff) even if you lose two engines.

The only abort scenario I know of that's actually occurred was an abort to orbit back in (I think) the early 90s, when the shuttle had an engine but made it into an orbit, albeit a lower orbit than the one planned.

<font size=-1>[ This Message was edited by: ToSeek on 2002-11-24 17:08 ]</font>

ToSeek
2002-Nov-24, 10:11 PM
It stands for Transoceanic Abort Landing, and here's (http://www-pao.ksc.nasa.gov/kscpao/nasafact/tal.htm) more than you probably want to know about it:



The four sites NASA has designated as TAL sites have been chosen in part because they are near the nominal ascent ground track of the orbiter, which would allow the most efficient use of main engine propellant and cross-range steering capability.




_________________
"... to strive, to seek, to find, and not to yield." - Tennyson, Ulysses

<font size=-1>[ This Message was edited by: ToSeek on 2002-11-24 17:12 ]</font>

Silas
2002-Nov-25, 12:21 AM
I was curious: on CNN Headline News, they said that the launch was very loud, and they quoted NASA as saying it really shook up the place. Was this a more "violent" launch than usual, or was this just typical news hyperbole?

Silas

2002-Nov-25, 12:23 AM
All of the things that I have read about NASA mission control focuses on the premise that orbit (even if it is a lower one than originally planned) is the safest place for a spacecraft to be in the event of a problem because it gives the mission controllers and pilots some valuable breathing space during which they can more accurately assess the nature of the problem. Also it gives them much greater control over the spacecraft's return to earth.

Pre-orbital aborts are very risky and occur under less than optimal levels of control and would only be done as a last resort as defined as by the mission rules.

Also in response to the person who indicated thayt Spain would be an ideal place for terrorists to do something to a Shuttle I think you were over reacting a little. It would have to be a extraordinary series of events that would get a Shuttle in such a situation where it is needed to emergency land in Spain and then the terrorists would then have to quickly organise an attack and then execute it against what would be unusually high security. As I said highly unlikely.

ToSeek
2002-Nov-25, 01:08 AM
On 2002-11-24 19:23, steve_remington wrote:

Pre-orbital aborts are very risky and occur under less than optimal levels of control and would only be done as a last resort as defined as by the mission rules.



Definitely. RTLS (return to launch site) aborts are particularly hairy because the shuttle has to turn around, burn off as much fuel as possible, get rid of the external tank, and get in position for landing, all with a vehicle that is by definition having problems.