Domain: spaceline.org
Stories and comments across the archive that link to spaceline.org.
Comments · 15
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Re:"Close" Only Counts
Armstrong was an exceptional pilot, I read on old NASA report about him regaining control of a space capsule that started spinning before it could kill them. Something to do with a malfunctioning thruster rocket.
Here it is:
"And, make a decision he did. In a rule-breaking move, Armstrong manually disabled the OAMS thrusters and activated the re-entry control system (RCS) thrusters to stabilize the spacecraft. With hand controllers aboard the spacecraft now functioning properly, correct motion of the capsule was restored."
http://www.spaceline.org/fligh...Yeah, they were 'hands on'
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Re:Have you seen the rocket?
It's nowhere near the complexity of the Shuttle. It's great that they can launch a rocket cheaper than NASA can launch a shuttle...but you're comparing the cost of a garage of a Pinto to that of a Lamborghini.
The shuttle was a series of mistakes. First there were the design compromises necessary for accommodating the defense department's wanting to launch bulkier payloads at high angles to the elliptic, for a large reduction in capacity. Then there was the whole fiasco with costs and turn-around times for each launch because it has to practically be re-built each time. So much for 25 to 60 flight a year.
Evem early in the game, the solid booster system was known to result in a cost increase of 60% per pound into orbit.
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Re:implied
Do you really think that if the government didn't have NASA that there wouldn't be "stupid government restrictions" on firing large missiles into the atmosphere and beyond?
The existence of the Space Shuttle was used to hinder privatization, so yes.
And the Space Shuttle was an utter (and expensive) failure compared to its original design goals - "NASA expected the Space Shuttle fleet to ultimately complete 25 to 60 missions per year. Plans called for up to 20 launches per year from each of three launch pads." http://www.spaceline.org/rocketsum/shuttle-program.html
I do not hate Dick Nixon because he was the usual scum sucking Washington swine dog of a politician they all seem to be. I do hate him for approving the Space Shuttle and perhaps ruining my chances forever for going to into space.
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Re:It's amazing that this was not done initially
I didn't mention manned missions but development and engineering practices.
Take the example of the rocket engines developed independently by both sides . The American F-1 design didn't use staged combustion cycle because it was deemed unstable and unpredictable denying their engine a the vast performance boost. At the same time, Russians developed and tested the RD-170 using the staged combustion cycle. The development ended in 1976(!) and proved to be more powerful than the F-1A (Saturn V 1st stage) engines. All the RD-170 engines were to be scrapped but were preserved by the Russian engineering team. About 20 years later they were sold to the west which still didn't have engines as efficient.
The Atlas IIIA flew in 2000 using RD-180 engines - a scaled down version of the RD-170. -
Re:That kind of efficiency is impossible
What makes this work is that the chamber temperature is way higher than can be contained by any materials that we can make - so they cool the chamber walls (which would be an efficiency loss) but they cool them with propellants (so that the energy lost is put back into the system). So the engine itself has virtually no losses - and if you put a large enough nozzle on it, you can take it to just above the boiling point of water. So the engine can go from 3300 C (the SSME combustion temperature) to about 50 C (nozzle exit is way below atmospheric pressure, so the boiling point of water is lower). Efficiency = 1 - 350/3600, >90%. Several engines like this were designed, but since it would only make sense on a very long term deep space mission, I don't think anything this efficient was ever really built.
As a more concrete example, the Space Shuttle Main Engines (SSME) have a combustion efficiency of 99%. So the only thing that makes the total efficiency less than 99% is that the engines must operate in the atmosphere - so the nozzles cannot be too large (the exit pressure needs to be close to one atmosphere). The overall system efficiency of the SSME is 76%. More efficient engines have been made (look at the J-2 or any upper stage hydrogen engine), but this one everyone is familiar with.
Note that an inefficient rocket engine is a really bad idea - the SSME are 6.4 GW reactors, and are only a few meters long. Think about it - any losses in the engine (wasted heat) would need to be radiated away. What temperature would it have to be to radiate away 5% of 6.4 GW?!? -
Re:*Sigh*
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Re:*Sigh*
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Re:*Sigh*
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right stuff to ask questions'... some retired guy
...'Yes John Young is some old retired *guy*. But he's a reminder of a generation of real acheivers. Forget the awards and look at what he has actually done:
Born in depression era America he graduated from Georgia Tech in Aero class of '52, (for all you pre college persons - it's one of the harder enginering courses), while his armed service combat record only mentions service in Korea on DD-558, Young flew Crusader and Phantom test pilot missions evaluating weapons systems, breaking speed records at 3000 and 25,000 ft. He retired as a Caption after 25 yrs Navy service in '76.
Youngs Nasa career started in '62, flying Gemini 3 missions in '65 with Gus Grissom (remember Grissom, Commander of Apollo 1 which tragically burnt on the PAD), Gemini 10 in '66, CMMP on Apollo 10 in '69 (test run for Apollo 11 in - so thats around the Moon), Apollo 16 in '72 (with Ken Mattingly who missed his ride with Apollo 13 - so he has worked on the lunar surface for his day job), Commander of STS-1 (that the first shuttle flight) in '81, Commander of STS-9 Spacelab in '83. Was backup in Gemini 6, Apollo1, Apollo 7, 13, 17.
In summary 15,000 hrs training, 15100 hrs in flight hours and 835 hrs in 6 space flights.
He's some *retired guy* all right. He is one of only 12 people who have walked, worked and lived on the moon. That give him a unique insight into this area. He has seen how puny Earth is from space and realises how human existance is not something to be taken for granted. You can read more about his bio here.
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Re:Why did they choose Floridia?
Here's a good link regarding the choosing of Florida for the space program.
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Gemini 3
One, no military pilot in his right mind would deliberately FOD the cockpit
You're right, I can't imagine this ever happening on a NASA flight either.
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Reinventing the Wheel
Didn't the Germans research a lot of this during WWII? Also some Americans.
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Glenn's re-entrythere is only a small chance and a big prayer then that the shuttle will survive the re-entry.
Kind of reminds me the re-entry of Friendship 7 (John Glenn's flight) when the heatshield had apparently became loose in the orbit. The retro-rocket package that was strapped to the bottom of the capsule was not jettisoned until the last possible moment in the hope that it would hold the heatshield in place. A small chance and a big prayer indeed.
It turned out to be an instrumentation failure
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Re:Older rescue
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Re:Challenger
Well you can organize them in alphabetical order but that's not how they arrived.
Enterprise was first, it was the "prototype," used in test flights in 1977.
And yes it was named in honor of the Starship Enterprise of Star Trek.
Then Columbia (first mission: 1981), the first to actually fly in space.
Then Challenger (first mission: 1983),
then Discovery (first mission: 1984),
then Atlantis (first mission: 1985),
then the lastest shuttle Endeavor (first mission: 1992).
IIRC It was sometimes called Phoenix, before its completion.
Here is the page where I got the shuttle chronology:
http://www.spaceline.org/shuttlechron.html
We should all honor the memory of the crew of Challenger.
The special mini-magazine in the newspaper on Sundays, Parade, had a nice article on the Challenger Learning Centers, here is a link:
http://www.challenger.org/clc/clc_netw_set.htm.
The families of the crew started this science learning center in honor of them.