NROL-76 Launch Webcast
Start at 6:30
[youtube]https://youtu.be/EzQpkQ1etdA[/youtube]

+1

And there are still those people who think airplanes "will never be able to fly without a pilot". Ha!!!

impressive. landed dead center.
amazing what genius kids can do when they get together

"Be back in ten minutes."

"Where you going?"

"Space, my boy. I'm going to space."



Seriously, nine minutes to space and back. Sometimes it takes me that long to find my keys.

Simply amazing. I'm astounded at this.

I realize the goal of landing this is to re-use it. But how much burn and usage damage must be repaired to ready it for another launch? Any idea what the landed section would cost if destroyed?

Yes, it is astounding. In addition, there are a lot of very smart engineers working on driverless vehicles. I was driving on the 405 freeway yesterday and noticed how inefficient humans are when driving. Someone will see a brakelight hundreds of yards up and start braking, that starts a chain reaction and soon the freeway is backed up. Computers wouldn't do that. As for the cost savings to SpaceX to reuse the 1st stage is certainly in the tens of millions.

Since they say cost of relaunch is 50% and you need to refuel I'd say the stage 1 hardware costs about 75% of launch cost, 25% for fuel, some TLC and some profit on relaunch and you are right at 50%.

I think what Space-X is doing is really impressive, but there's something I don't understand about their design approach.

It seems to me that the hardest part of this process is the actual placement of the rocket back on the pad on the landing legs (the flare, so to speak).

But since I imagine that the rocket then has to be taken down and trucked back to a building to be refurbished before it can be reused, why not simply deploy parachutes after re-entry and slowdown over the landing area? I realize it would be a less-glitzy, 'low-tech' solution, but I would think it would also be lighter, simpler, and cheaper.

My question is, is it not possible to get rid of enough energy after the re-entry burn, to make a parachute landing slow enough and damage free? Or are they doing this for style-points (and because this is how rockets landed in late nineteenth century adventure stories)?

I would think a parachute landing would be much more difficult to control....

I will promise, if a parachute was cheaper and more effective, that's the route they would take....

View everything the Space-X does through this lens:

Elon Musk wants to go to Mars- Land upright in his rocket just like Buck Rogers then perhaps return to Earth if he finds Mars boring. His rocket must be very good at landing since he probably doesn't want to die before he can play with Mars rocks. His company is going to need lots of practice to get this right.

Now all the design tradeoffs that might favor other approaches to launching satellites make sense.

Even if they could make the landing slow enough, the control issues would still be there... Most of their launches do not allow for land landings, so they need to land the booster on the floating platform. If they splash down under the parachute instead, it's gone...

My guess is that parachutes are open to wind and chute variables where the reentry rocket need to be discriminate and controllable. Mitigate risk.

Okay, but ...

I've seen skydivers using controllable parachutes make spot landings before. Surely if we can build computers to land a rocket upright on a launch pad, we could make a computer capable of flying a parachute? Add a few thrusters to stabilize the rocket and I would have thought the control issue is done.

BWTHDIK

Amazing

The stated goal of SpaceX is manned Mars missions. They cannot rely upon a chute in the thin Martian atmosphere for anything heavy enough for a manned mission. So I think they are doing this so that they will have years of rocket power on landings under their belt when the time comes. I'm not saying a Mars mission is a go for next week or anything close to it. I'm basing my reply on what they have said many times publicly.