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Space Shuttle Discovery to Launch July 26
thhamm writes "According to Space.com: 'NASA will restart the countdown for the space shuttle Discovery Saturday, with plans to launch the orbiter spaceward on July 26 after more than a week of work to pin down a fuel sensor glitch, mission managers said late Wednesday'. In the meantime, technicians will work with grounding wiring associated with the liquid hydrogen engine cutoff sensor system, as well as adjust the configuration of components within Discovery's point sensor box."
With a DMM, since 480VAC mains power with a bad ground can get your attention.
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would be for some sort of non-lethal disaster to happen that severely damages/destroys the Shuttle but doesn't kill the crew. Perhaps some accident on the landing, or some sort of problem before launch but where they can get the crew off safely but still destroys the shuttle.
This way, we can finally get rid of the pork politics blasphemeies known as the Shuttle and the ISS and start investing money into a real, sustainable manned space program, instead of this ridiculous horse and pony show.
We need some successful manned missions so we can do more interesting stuff than orbit Earth.
1992 called, no we don't.
--
WHO ATE MY BREAKFAST PANTS?
So, you get readings at some point in time. You then force through a voltage within tolerence limits but definitely higher than normal, to increase the temperature of the wiring. You measure the resistance again. The circuit with the bad wiring will increase in resistance more than the other wires.
Once you know WHICH line (from end-to-end), the task is easy. You find the mid-point and see which half has the greater resistance, and repeat. Simple binary search.
Alternatively, you do a full tank test, to recreate the cooling.
In the meantime, there is supposed to be a shuttle in standby configuration, in case the astronauts get stuck in space. Is the standby shuttle getting tested as well? If (as could be the case) it is a faulty batch of transistors in one of the components, then the backup shuttle would likely have the same fault. If the main shuttle is to launch on Tuesday, they kinda need to find this out NOW.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
There are three possible outcomes to the launch attempt, only one of them is completely positive:
1. Discovery launches Tuesday during the launch window and has a routine and successful mission. After that, there will be plenty of time to determine the root cause of the sensor issue.
2. The weather does not co-operate or another tenchnical glitch surfaces, causing Tuesday's attempt to be scrubbed. NASA is hounded in the press for being unable to manage their spacecraft, when in fact they are doing exactly that according to their safety protocols, which have been generally tightened post-Columbia.
3. Disaster. Unthinkable and possibly the end of an American manned space presence until the Crew Exploration Vehicle is completed and launched in the next decade.
The Space Shuttle is an aging flying compromise that has been updated as much as possible, and it is what NASA has been given to work with. I almost expect Outcome #2, given their justifiable prudence in halting launches when they are not 100% satisfied that the system is as operationally ready as they can make it. NASA may be criticized for delays, but when seven lives and a multi-billion dollar spacecraft are on the line, not to mention all of their political capital, once can understand why they do what they do.
Bottom line is that all eyes will be back on the Cape come Tuesday morning. Godspeed Discovery.
...they can make a small space on board and take Scotty's ashes with them... seems only fitting.
Now what I can't imagine is how many times more difficult that is when true "ground" ends up being over 100 kilometers away!
-- I'm not a pessimist, I'm a realist. It's not my fault that life sucks so much. --
I've been wanting to go see a shuttle launch for a while. This one's on a weekend, which makes it possible.
They're starting the countdown on the weekend. The actual launch is on Tuesday.
That is *way* too long a drive. If you're going, just fly into Orlando and rent a car for the drive to the east coast. I did it last week, and round trip airfare from Philly was ~$275 and the rental car was $40. I left my house at about 5:30am and got home again just before midnight, and I only had to take one day off from work. Spending 24 hours in the car, including some in launch day traffic, would wipe me out for a couple days.
~Philly
This sounds hauntingly familiar. In the first disaster NASA had simply gotten used to seeing some burn-through on the o-rings to the point that it was "normal", in the second disaster they had seen foam and ice come off the orbiter but nothing bad had happened so far.
In the third disaster they couldn't find the cause of the fuel sensor problem so they declared that only three were needed and launched anyway.
Bob Cowell writes an excellent column in Computer magazine. In one column titled "Murphy Was Wrong" he points out that unlike Murphy's Law, things usually go right in spite of a myriad of glitches. In fact, they go right so often that people start ignoring the warning signs. It usually takes a severe or multiple failures to cause an actual catastrophe.
If something is failing it is failing for a reason. Don't launch till you know the cause and for gods sake don't "solve" the problem by simply rewriting the rules to say that it's OK for a "critical" system to fail.
As cool as the space exploration and the shuttle are, it may be time to say that the program has utterly failed to meet its goals, will never be able to meet its goals, and that we should cut our losses, take the information we have learned from the shuttle program, and move forward on a replacement.
Consider that the stated goal for the shuttles was 100 missions each. Unfortunately that's pretty close to the tally for the whole fleet. Oh, and there is that little annoying fact that 40% of the orbiters have crashed killing all aboard.
~~~~~~~
"You are not remembered for doing what is expected of you." - Atul Chitnis
unmaned? Their knock-off of our shuttle did two orbits and a landing that can only be described as tits. Now since the main purposes of this shuttle flight are 1) proof-of-concept/testing of all of the modifications and 2) resupply space station....
Well if the damn thing blows up on launch like challenger then, i guess they need to rework it. If it burns up on reentry then maybe they should look over their blueprints. But if it doesn't blow up at all, then mission completed and no lives (not even a monkey or a puppy) need to be risked.
I mean the shuttle does do reentry and approach with the control to computers, hands off pilot, correct?
I think lowering the landing gear is the only thing that requires a manual input and is not fly-by-wire. But I'm sure those geniuses could rig up some kind of contraption with wires and marbles and ice cream attached to an egg timer that would lower the gear at the right moment.