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Longer Video Shows How Incredibly Close Falcon Stage Came To Successful Landing
Bruce Perens writes In the video here, the Falcon 9 first stage is shown landing with a tilt, and then a thruster keeps the rocket vertical on the barge for a few seconds before it quits, followed by Kabooom with obvious significant damage to the barge. It looks like this attempt was incredibly close to success. Given fixes, a successful first-stage recovery seems likely.
Probably not when they figure out how to land on the barge without exploding... at that point the damage from hitting the water and amount of cleaning & service required to be read for launch will be much more.
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Why am I not convinced your way sounds like the "easy way"?
I can't event think of the mechanical stresses involved in opening this thing up to spin it around.
In fact, it sounds outright crazy.
And that's before we start considering a fuel tank designed to open up. Because, what could possibly go wrong there?
Lost at C:>. Found at C.
Oh, they're Canadian. That explains everything!
(Ducks and runs for cover)
:-)
Bruce Perens.
With Horseshoes and Hand Grenades. We've seen what "close" gets us with rocketry, and it's not pretty.
Not until the next time we cut the NASA budget to pay for a subsidy of some incredibly rich industry. Like oil. We need more oil drilling subsidies, don't we? Or intellectual property. That's just another word for innovation, isn't it?
Bruce Perens.
Hard to splash down on the moon, Mars, asteroids and just about everywhere else we want to go. We'll have to get it right eventually, might as be now. Bonus benefit: cheaper than overhauling the engines every time. You'd think with them doing this at a third the cost of anyone else, WITH A PROFIT, that people would understand that they know what they're doing. Yes, there will be early failures, but this doesn't add that much cost, especially considering long term payoff.
Watch for Penguins, they eat Apples and throw rocks at Windows.
I suppose magnetic/sticky harpoons might help (you don't want to damage it after all), sort of like guy-lines on an airship. I don't know about a shock-absorbing landing pad (your catcher's mitt) though - in the moments before landing the backwash would be subjecting it to forces exceeding those of the weight of the rocket itself - probably at least as difficult to tune any "give" to occur at the proper moment as i is to land the sucker in the first place.
Plus, as others have mentioned, Musk seems to have his eye on Mars. Landing a colony ship can probably only be done by rocket, and there won't be any special landing pads on Mars. Plus, for more terrestrial concerns, if he can master landing on a simple barge, he can land pretty much anywhere, which dramatically improves the value of his rocket design onte international market: any bit of flat, stable land is a potential cheap spaceport that his rockets can service.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
That would be hot for an aircraft, but it was the planned vertical speed profile for the rocket. The grid fins need speed to work and they are the main control surfaces. The cold gas thrusters don't have infinite gas behind them and the engine burns are very short.
Bruce Perens.
I was surprised by something in the re-entry profile. They use what they call "lift" from tilting the rocket body against the air stream to control horizontal motion. I call it "falling with style". So they can go back uprange some distance without an additional fuel expenditure.
All of their communication so far has been that they can get back to the pad with the F9 or the two outer stages of the F9 Heavy. The center stage of F9 Heavy would probably need the barge.
Bruce Perens.
They hit a barge in the middle of the ocean with a gigantic rocket that was nearing orbital velocity. I think we need to cut them some slack :)
A booster is really a pretty fragile thing. It's designed to be really strong in one axis only. It also has to be lightweight. Grabassing the thing from the sides is going to make for a bunch of expensive scrap metal.
Faster! Faster! Faster would be better!
Rockets are capable of incredible acceleration, especially when they're low on fuel and deprived of their payload. Under those conditions, the F9 first stage could easily go from 50MPH (~22m/s) to 0 in the space of a few meters.
Also, you *want* to land fast, because for every second you spend in the air you lose another 10m/s of your limited delta-v (fuel), and the faster you're traveling the more aerodynamic control you have.
Yes, I know all this from playing KSP.
How can I believe you when you tell me what I don't want to hear?
Remember: seawater ruins everything.
You think landing on a body 1/6 of Earth's gravity, without an atmosphere or weather, and under the control of a human is really comparable to landing on Earth, with full gravity, atmospheric weather systems, and all controlled by a computer?