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107 Cameras to Scan Discovery for Damage
neutron_p writes "We already know that NASA has prepared for space shuttle rescue mission if a crisis arises during Discovery's return to flight. NASA wants to avoid any risk, that's why they also installed 107 cameras which will film and photograph the orbiter's first two minutes of ascent from every angle scanning for pieces of insulation foam or ice fall off during the launch and strike the shuttle, the kind of damage that doomed its predecessor Columbia. Cameras will be installed around the launch pad and at distances of 6 to 60 kilometers (some 3.5 to 35 miles) away, as well as on board of two airplanes and on the shuttle itself."
I don't know where the article got their conversions from but I sure hope it wasn't from NASA!
6km is approx 3.7 miles not 3.5 and
60km is 37 miles and not 35
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Sigs are like arse-holes, everybody has one
Then they could ditch aboard the ISS (which is where they're going) then take a Soyuz capsule back to earth.
There *was* an ejection system, but it was removed after the first few flights since it only provided for the pilot/copilot. It was only there for the initial test flights. If they had kept it, the other crew would have been SOL, so they dropped it.
The Soyuz capsule only has a capcity of 3, so there would be no way to get the entire crew back without launching an additional shuttle or Soyuz.
How do the Russians launch their vehicles one after another without lots of funfare but with almost success? There have been almost 2,300 successful Soyuz launches and just 11 Soyuz failures ever...! That's a success rate that cant be beat! To make matters worse, they do it cheaper too!
The point of the cameras is to determine if something broke on the shuttle. If something breaks the shuttle will not return to Earth. The cameras aren't there to say "OMG, SOMETHING WENT WRONG, ABORT." The cameras are there to determine if something went wrong and if so, to send the backup shuttle into space to return the astornauts safely to earth.
NASA reviews the tapes and assesses whether or not the point of failure is avoidable or is an inherant flaw of the shuttle system.
crazy dynamite monkey
The first, RTLS (Return To Launch Site Abort Mode) can be initiated upto T+4mintues20 and involves an early ET (External Tank) seperation followed by a powered phase to bleed of excess fuel and a glide phase which see's the orbiter return to KSC at approximately T+25minutes.
The second is the TAL (Transatlantic Abort Landing). This can be initiated in the event of critical failure after T+4minutes20. The orbiter continues in a balistic trajectory downrange across the Atlantic to land at a runway in Spain, Gambia or Morocco. Landing occurs T+45minutes.
>AFAIK there is an ejection system.
Nope. There used to be ejection seats on Columbia for the Commander and Pilot, which were useful to 100K feet. (If you listen to recordings of the first four launches, you'll hear a call from the CAPCOM, "Negative seats" or somesuch as the vehicle passes that altitude.)
They weren't used after the first four flights, and were removed when Columbia went in for its first refurb.
The shuttles have a very limited on-orbit lifespan; they quickly run out of fuel for the fuel cells, coolant, etc. They make lousy space stations. The average shuttle mission is ten days, and the maximum is 18 with the Extended Duration Orbiter upgrade.
If you docked one with the ISS, I'd expect it to very quickly die --- and once dead, I doubt very much whether doing an in-orbit renovation to get it into a sufficient state even to land it on autopilot would be feasible. (If there is and autopilot.)
Given the sheer mass of a shuttle and how much stress it'd put on the ISS' station-keeping facilities, I strongly suspect that in the event of an on-orbit failure, the crew would be evacuated and then it'd be given the heave-ho into the Pacific...
1. They will be spacewalking to test exterior repair, if it works, they can fix it on orbit.
2. They're going to be visiting the station - this mission is reportedly rigged so that if something really bad is found, the can stay on station until another shuttle can be launched.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
- RTLS - Return to Launch Site
- TAL - Trans Atlantic Landing (European and African landing sites)
- AOA - Abort Once Around
- ATO - Abort To Orbit
So, if there is a problem, and they find it early enough, they have options."I'm not impatient. I just hate waiting." - My Dad
Basicly to match vectors you have a very small launch window. You will either aim for ISS or for the escape pod. If you have just lost 25% power at one of the main shuttle engines you just lost your window. You will have to follow an alternative plan. This is why all this "stay safe in ISS" is a bullshit plan. It will only work if a tile gets loose. It won't work in Challenger-type scenarios (which there is no escape with the current Shuttle tech) nor Columbia (something happens unnoticed and you have the failure in the re-entry).
Going up and down is easy. Changing vectors and orbit is just too expensive in energy terms so you don't do it. The whole point is getting it right the first time.
While RTLS seems simple enough, there is one key aspect which should not be overlooked, "With as little of the fuel remaining in the ET as possible the shuttle executes a powered pitch around maneuver (PPA) where the orbiter and the ET rotate 180 degrees; so that the craft is headed back to KSC. The orbiter is now on top of the ET at this time and the remaining SSMEs are still operating." That is, the already large orbiter plus the even larger external tank will flip nose over to re-orient itself with the landing site, this all while the engines are going full bore, and while still in the atmosphere. This dramatic flip which must occur could put more stresses on the orbiter than experienced during a typical re-entry from the enormous friction caused by the atmosphere on the skin. In the case of skin damage issues, such an abort method could easily prove fatal, limiting the abort options even further.
The shuttle's engineering design also specified no foam loss as a requirement. Over time, foam loss became tolerated, with a pervasive management attitude of "well it hasn't caused any problems, yet". Damage to the shuttles' carbon panels was documented on numerous missions, and was ultimately treated by management as a post-flight maintenance issue, rather than as a safety issue.
This sort of complacency is what killed Columbia, and is well documented in the extremely interesting Accident Investigation Board report.