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Shuttle Fleet Upgraded
angel'o'sphere writes "Space.com reports that the shuttle fleet will be upgraded with more technology, like new sensors to detect debris hits on the wings, etc. Also, the foam causing the Columbia accident (intended to insulate the tank and prevent the formation of ice) will be replaced by: heaters. I wonder if heating up a tank with liquid oxygen is a bright idea."
"Those changes will be included as the direct result of the Columbia Accident Investigation Board's final report, released in August, which detailed 15 recommendations NASA must do before resuming shuttle flights"
I, for one, am appalled that it took a spectacular explosion, mass media coverage and the unfortunate deaths of shuttle crew to be able to reach this point. Is this really what is required to be able for technology to advance? I once heard in a movie once, that the shuttle was the result of "the cheapest bidder". These are scientists that forsaw this coming a long time ago, and just to save their jobs and pride they kept quiet about the failures in the previous shuttle. Lets hope these boys grow some backbone in the newest version, and not try to cover it up with bells and whistles just to satisify the publics anxiety.
Trying to land anyway may well have been the best option left, granted.
However, how sure are you about the no way of repairing part? The shuttle standard inventory shows some tile repair components onboard. If they aren't at least some use on the leading edges of the wings, it would be nice to know what they ARE intended for. Sprucing up a just landed shuttle before the press gets there to photograph it?
While we're at it, the later reports have included the possibility of a rescue mission using another shuttle, and the ultimate board conclusion is this is too risky, but notice, there's no breakdown of the risk assessment made available to the general public.
Obviously, a rational risk assessment would be different for a shuttle developing a problem that is an unusual, apparent fluke accident, or one that might well be developing on the rest of the fleet as well, and for a problem known about soon after launch as opposed to when there's only 3 days life support left. How did such considerations get rolled up into the blanket risk assesment made public?
Who is John Cabal?
If keeping it from going below a certain temperature by insultating it is OK, then heating it to that temperature would be OK. Why would you think otherwise?
No shuttle missions ever flew from Vandenberg, although there were quite a few landings there.
Part of the reason is that the launch facility was rife with problems. However, the bigger reason is political, in my opinion. Basically, NASA needed the Air Force as reluctant partner in order to get funding from Congress for the shuttle program. From what I understand, the Air Force was interested in using the Shuttle to put spy satellites into polar orbit.
Polar orbit is not something that could be achieved from Kennedy primarily because NASA would never risk putting the Shuttle on a trajectory where early launch failure could result in the orbiter and boosters plowing into a populated area. One does not have such worries at Vandenberg with nothing but desert and Canadians in tehe way should the Shuttle fail.
The numerous problems with the Vandenberg facility (rumoured to have a Native-American curse on it), some really bad press coverage and changes in Air Force administration resulted in the abandonment of SLC-6. The Air Force figured that they could get their spy sats into polar orbit more easily and cheaply with Titans.
BTW: If a Shuttle had ever been launched from Vandenberg, I think it would have been the Discovery. If I am remembering correctly, as part of the deal NASA struck with the Air Force, they actually got ownership of the Discovery. I apologize if any of this is factually incorrect, I am pulling straight from memory here. If you peruse the sci.space.shuttle newsgroup you'll find some truly informative articles there from people who really know about this stuff because they were the ones who actually worked on the shuttle program.
Nope. No shuttle ever launched from SLC-6. My dad was a flight operations analyst at Vandenburg from 1983-1987, so he would know. SLC-6 was originally built to launch the shuttle into a polar orbit -- the shuttle would launch in a southerly direction. (You can't launch into a polar orbit from Canaveral because the spent solid-fueled boosters would fall onto Brazil, and that would probably torque the Brazilians off.) Unfortunately, the solid rocket boosters were redesigned after the Challenger accident, and enough weight was added to preclude ever launching into a polar orbit, so SLC-6 was, in fact, abandoned. I was last there in 1996, and it was rusting out pretty badly.
Also, they've used heaters on liquid O2 before. I was reading "Moon Lost" by Jim Lovell (the Apollo 13 astronaut), and he explains that heaters were used in the Apollo spacecraft's O2 tanks to keep the system pressurized. O2 pressure too low? Just turn on the heaters, more of the supercritical O2 would resublimate, pressure's back up to nominal. In fact, heaters were chosen instead of pumps because pumps have more moving parts which means more things that can malfunction.
"I wonder if heating up a tank with liquid oxygen is a bright idea."
They had heaters *in* the oxygen tanks at least on the Apollo missions. Such a heater was in part responsible for the Apollo 13 near-disaster, though that was caused by a whose string of failures.
They had two weeks of food and three weeks of oxygen. The only options visited in the accident investigation reports are a rapidly deployed Atlantis and on-orbit repair. The former would provide a maximum window of five days assuming absolutely zero error in processing. Considering that would be rolling a three-month process down to two-weeks, one can imagine that likelihood. The latter solution included the possibility of a crew bail-out in case the wings were expected to completely collapse on landing. Bottom line: THREE WEEKS. You don't just lob a Soyuz into the air and hope it hits a shuttle in THREE WEEKS. Sure, there are lots of things that could do the job, but organizing that to happen in less than a month? The crew would die on flight day 31 due to lack of oxygen and it took until day eight just to get all the imagery in line. Now, I don't claim to be qualified in astronautics, but I'm going to give the benefit of the doubt that three weeks is a pretty tight schedule to execute an impromptu orbital rendezvous. Rather than accusing a casual observer of being ignorant, go read the damned report. I trust the findings there to any armchair astronauts on /.
http://www.caib.us/news/report/pdf/vol1/full/caib_ report_volume1.pdf
As mentioned in another response to someone else eager to crucify me for stating the obvious, READ THE DAMNED REPORT. They estimated that at best the repairs that were remotely possible might still result in an on-approach crew bailout as the wings might still be so damaged on re-entry that the shuttle would disintegrate on touchdown as essentially they'd be working with toiletpaper and bond-o.
i b_ report_volume1.pdf
http://www.caib.us/news/report/pdf/vol1/full/ca
Lets start with the Saturn V rocket. The thing was designed by the Huntsville Germans. When you think of German engineers, think meticulously designed and crafted, expensive as heck, and reliable. Did they ever lose a Saturn (Saturn V or Saturn Ib) in flight? Titan was much cheaper than Saturn but hasn't had quite the same record.
OK, now consider the Apollo CM with its ablative heatshield and low-lift blunt-body design. And with a Max Faget solid-fuel tractor escape rocket. Compare with Shuttle with wings, and tiles, and computers flying the thing and with the Shuttle parallel to the tanks where stuff can fall off or blow up. In the Challenger explosion, the crew capsule remained intact and killed the crew when it hit the water. If something happened to the Saturn rocket, the Apollo crew had an escape rocket, they had space suits to survice a cabin puncture, and they had parachutes to make a safe water landing.
Sure Apollo was primitive by comparison, primitive in the sense of Keep It Simple, Stupid (and Safe). Oh, and Apollo had redundant space crafts so even when the Service Module was blown to shreds (as a result of ground handling to empty a balky oxygen tank by running tank heaters until the insulation burned off), they brought back to crew, although one guy had a 103 F plus fever from a urinary infection because he didn't think they had enough electric power for him to take a leak often enough.
Give me Apollo primitive over Shuttle any day.
http://www.floridatoday.com/space/explore/special/ slc6/slc6.htm
It's not really the energy that's the problem - if you've got a good nuclear reactor.
The problem is propellant. Where you gonna store the propellant? Much of your first half of the store of propellant is expended in accelerating the second half along with the ship.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
"Also, the foam causing the Columbia accident (intended to insulate the tank and prevent the formation of ice) will be replaced by: heaters. I wonder if heating up a tank with liquid oxygen is a bright idea."
:)
Hate to burst your bubble, slashdot, but the foam being replaced is NOT the foam surrounding the entire tank. That foam was not the problem.
The foam that caused the problem was a spray-on foam surrounding what NASA calls the "bipod region" - the connectors attaching the External Tank to the Orbiter itself. Moisture beneath this spray-on foam, according to failure analysis, undermined the structural integrity of the foam itself, causing it to break off during launch, which struck the Orbiter's leading edge - as I'm sure you already know.
However, only that spray-on foam will be removed from the external tank. Additionally, the only heater being installed on the External Tank will be a strip heater for only those connectors between the External Tank and the Orbiter - to keep ice off of the surfaces, which is a potentially bigger hazard than foam chunks.
How do I know? My dad's the NASA on-site chief engineer at the Michoud Assembly Facility, which builds the External Tank. So... I guess it really doesn't take rocket science to know that the simplest solution really is the most effective... does it?
Ignoratio Elenchi - Non Causa, ProCausa - Tu Quoque