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The Rise and Fall of NASA's Shuttle-Centaur (arstechnica.com)
An anonymous reader writes: An article at Ars Technica tells the story of Shuttle-Centaur, a NASA project during the mid-1980s to carry a Centaur rocket to orbit within the cargo bay of a space shuttle. As you might expect, shuttle launches became vastly more complex with such heavy yet delicate cargo. Still, officials saw it as an easy way to send probes further into the solar system. They developed a plan to launch Challenger and Atlantis within 5 days of each other in mid-1986 to bring the Ulysses and Galileo probes to orbit, each with its own Shuttle-Centaur. Though popular opinion at the time was that the shuttle program was "unstoppable," individuals within NASA were beginning to push back against slipping safety standards. "While a host of unknowns remained concerning launching a volatile, liquid-fueled rocket stage on the back of a space shuttle armed with a liquid-filled tank and two solid rocket boosters, NASA and its contractors galloped full speed toward a May 1986 launch deadline for both spacecraft." The destruction of Challenger in January, 1986 put Shuttle-Centaur on hold. The safety investigation that ensued quickly came to the conclusion that it presented unacceptable risks, and the project was canceled that June.
It's a rocket with a ridiculously heavy intermediate stage that serves no function but to endanger lives if anything goes wrong.
I guess when you have a hammer...
How can I believe you when you tell me what I don't want to hear?
I used to say the Shuttle was probably capable of a whole lot more than what we knew of its capabilities (Even though it is NASA, and supposed to be fully transparent) - using its cargo capacity for extra fuel always seemed like a no-brainer to me. I had no idea this was actually pursued in a form, but it is a shame real life finally caught up to NASA and all the cool technological advances have been under military secrecy since then.
The only way NASA will get to Mars is by film.
An easy alternative would be to cremate a former NASA Administrator or former astronaut and send the can of ashes to crash on Mars. Otherwise if a Manned Mars Mission is NASA's survival option then NASA is already dead.
Besides, according to a National Academy of Sciences report, no human beings (alive) will journey to Mars, land, and return (alive) in the next foreseeable 50 years at least, which if you read carefully means that at least 300 years will pass before humans land on Mars, and that mission will not be accomplished by a government organization called the National Aeronautics and Space Administration from a country called the United States of America.
So, NASA going to Mars is all, academic. A badly written C- undergraduate term paper that was late.
Why not shuttle solid propellant? It can even be sent in parts and assembled later. Aerotech high power reloadable model rocket motors use ammonium perchlorate and the propellant can be stacked, making it unnecessary to ship large assembled motors. It's a simple design and way more reliable and safer than liquid fuels. There's no throttlability of solid propellant though, at least not in an easy way.
The video in TFA is really interesting. Definitely some tense moments (even knowing the outcome) when it went into Abort to Orbit.
Chance favors the prepared mind.
Perfect is the enemy of good.
Well, again, that's the soundbite version - and only half the truth. In reality, the worst cases of leakage prior to the loss of Challenger occurred with launch temperatures in the eighties. In reality, the real problem wasn't temperature but a phenomena called joint rotation. That's why the redesigned joints included heavier clevis pins at the joint (to prevent the two halves from moving relative to each other) as well as heaters.
Reference Nasa's own description of the redesigned joint - there's a reason why the new heater is mentioned almost as an afterthought.
By now we should be building the rockets in space and just delivering the materials from Earth.
Dammit Slashdot! We need more of this sort of thing, and less of people being pissed off because something got a file extension of .bro.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
BTW - when they're burning, SRB's produce very hot gas which damn well can leak .
Read the Wikpedia article on the loss of the Challenger or just search Google for "space shuttle challenger accident"
Yesterday I saw something about Challenger and its O-rings in a show that my DVR caught. Video showed that an O-ring was leaking at launch time, but managed to re-seal shortly after launch. Then crosswinds put enough stress on the SRB to unseal it again. Ouch.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
They don't know why it sealed though... whether it was flexing of the case, or condensation of the exhaust gases forming a temporary plug. (IIRC, there was signs that the latter may have happened during previous burn through and blow by incidents.) But it goes to show that the accident is much more complicated than the "it got cold, it go boom" urban legend version.