Slashdot Mirror
In Daring Plan, Tomorrow SpaceX To Land a Rocket On Floating Platform
HughPickens.com writes "The cost of getting to orbit is exorbitant, because the rocket, with its multimillion-dollar engines, ends up as trash in the ocean after one launching, something Elon Musk likens to throwing away a 747 jet after a single transcontinental flight. That's why tomorrow morning at 620 am his company hopes to upend the economics of space travel in a daring plan by attempting to land the first stage of a Falcon 9 rocket intact on a floating platform, 300 feet long and 170 feet wide in the Atlantic Ocean. SpaceX has attempted similar maneuvers on three earlier Falcon 9 flights, and on the second and third attempts, the rocket slowed to a hover before splashing into the water. "We've been able to soft-land the rocket booster in the ocean twice so far," says Musk. "Unfortunately, it sort of sat there for several seconds, then tipped over and exploded. It's quite difficult to reuse at that point."
After the booster falls away and the second stage continues pushing the payload to orbit, its engines will reignite to turn it around and guide it to a spot about 200 miles east of Jacksonville, Florida. Musk puts the chances of success at 50 percent or less but over the dozen or so flights scheduled for this year, "I think it's quite likely, 80 to 90 percent likely, that one of those flights will be able to land and refly." SpaceX will offer its own launch webcast on the company's website beginning at 6 a.m. If SpaceX's gamble succeeds, the company plans to reuse the rocket stage on a later flight. "Reusability is the critical breakthrough needed in rocketry to take things to the next level." SpaceX announced the plan in December.
After the booster falls away and the second stage continues pushing the payload to orbit, its engines will reignite to turn it around and guide it to a spot about 200 miles east of Jacksonville, Florida. Musk puts the chances of success at 50 percent or less but over the dozen or so flights scheduled for this year, "I think it's quite likely, 80 to 90 percent likely, that one of those flights will be able to land and refly." SpaceX will offer its own launch webcast on the company's website beginning at 6 a.m. If SpaceX's gamble succeeds, the company plans to reuse the rocket stage on a later flight. "Reusability is the critical breakthrough needed in rocketry to take things to the next level." SpaceX announced the plan in December.
Their engines are already reused "sort of". They test fire their engines before launch. One time they evens scrubbed a launch after the engines were lit. They fixed the problem in a few hours and launched after that.
One of the reasons payloads cost multi-billion dollars is because the launchers cause near that amount. Cheaper launchers will lead to cheaper payloads..
I love Jesus, except for his foreign policy.
The SRBs were re-used as well as the engines connected to the Shuttle itself.
The external tank is jettisoned too high to recover. It was thought that it could be used in space to construct something but that was never done.
Even if they can recover the engine intact how many times can it be reused. Saving a few million on a higher chance of blowing up multi billion payloads is not exactly wise economically.
Think of it this way: if they can fly the first stage 20 times, that along with some cost optimizations of the upper stage could cut the cost per pound by a factor of ten. Then it would become economical to launch mere multi-hundred million dollar payloads. That would dramatically reduce the economical risk of any single launch, as long as the rocket is not ten times as likely to blow up, but rather only maybe twice as likely.
Of course, anyone who launches a lot of rockets of the same type is likely to become really good at getting that type to orbit in one piece. Just look at the Russians and their now ancient Soyuz rocket.
Keep cutting costs and you might one day have a system where you could launch a ten million dollar payload, which you could easily insure at your local insurance company.
So, let's look at history for a (possible) answer. The Apollo flights were all "just came out of the VAB" flights. There were 40 of them, including a loong unmanned test series (17 manned flights). Counting Apollo 13, two of them failed. Which gives you 5% failure rate (including 13), or 2.5% failure rate (not).
Shuttle had 135 missions, with two failures. Failure rate ~1.5%.
So, shuttle, which "returned whole and was turned around for this flight" had a better safety record than Apollo, which "just came out of the VAB".
Note that if you substitute Soyuz for Apollo, you get similar results. Yes, Soyuz had two loss-of-crew failures, just like Shuttle, but in fewer than 135 flights....
"I do not agree with what you say, but I will defend to the death your right to say it"