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SpaceX Successfully Lands Its Rocket On A Floating Drone Ship For The First Time (theverge.com)
An anonymous reader quotes a report from The Verge: SpaceX has finally landed its Falcon 9 rocket on a drone ship at sea, after launching the vehicle into space this afternoon. It's the first time the company has been able to pull off an ocean landing, after four previous attempts ended in failure. This is the second time SpaceX has successfully landed one of its rockets post-launch; the first time was in December, when the company's Falcon 9 rocket touched down at a ground-based landing site in Cape Canaveral, Florida, after putting a satellite into space. Now that SpaceX has demonstrated it can do both types of landings, the company can potentially recover and reuse even more rockets in the future. And that could mean much greater cost savings for SpaceX.
The smallest launch cost is fuel -- the largest is hardware. The majority of the hardware cost is for the 1st stage. So if the hardware of the 1st stage can be re-used, how is this not a win?
You are simplifying it to such an extent that you completely miss the point. The cost of the fuel is a small fraction of the cost of the launch - the cost of building the 1st stage dominates. When that stage is destroyed, it is an operational expense for that launch. When it is recovered, it is a capital expense with an additional smaller operational expense to refurbish and another expense to account for the reduced efficiency of the launch (some fuel held in reserve as you say).
Since converting the huge operating expense into a a huge capital expense that results in an asset that can continue delivering value minus some small additional operating expense, the net result is a more economic system.
All rockets fly with lots of margin (read: extra fuel) in case of unexpected anomalies during flight. The difference with SpaceX is, when the flight goes as planned, they can use that extra margin to recover an immensely expensive piece of hardware. What's more, not all payloads are using every last pound of capacity in the vehicle. If you can launch 90% of the weight at half the cost thanks to reuse, you've fundamentally changed the market.
This is like getting to reuse a Boeing 747 instead of scrapping it after a single flight. If you think that's just a stunt, you don't have much of an imagination. This is a game changer.
It's automated. No humans aboard. That fits the commonly accepted definition of drone.
1st stage is $60M. Fuel is $250K. You do the math.
The only accurate point in your post is that second stage landings may not prove practical, which is why there are no current plans to attempt that. Fortunately the second stage is a lot cheaper than the first stage, in this case the second stage is just one engine compared to 9 in the first stage.
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SpaceX calls it a drone ship as well.
Dear lazy web, any higher quality video out there? Congrats SpaceX, this looks really impressive.
https://www.youtube.com/watch?...
I was gonna mark the parent as a troll, but really it's just uninformed.
https://science.slashdot.org/s...
Elon Musk says it takes $60 million to build the Falcon 9, and $200,000 to fuel it.
Steve Poulus, a former NASA project manager, suspects final costs could be driven below a million dollars.
So it's looking like a stunt that could be worth more than 95% of the first stage's $60M. That seems like a big deal.
They change the process after every flight, if the telemetry tells them they could have done something better. Just like they enabled the Dragon's parachutes during ascent on this flight, in case the rocket blew up. (The previous flight the 'chutes were disabled on ascent because it was assumed an explosion would be non-survivable, so when the Dragon capsude did survive the explosion, it was destroyed when it hit the water.) The odds of that making a real difference on any upcoming flight is minuscule, but it was a no-weight software change so why not? (Of course, they put considerable effort into making any software change reliable and predictable, unlike the vast majority of software out there.)
Continuous improvement. They may well change the process after this successful landing depending on telemetry, or may decide that it is good enough (for now).
Uh... yes. They've changed the volume of on-board hydraulic fluid, they changed the leg lock-out mechanisms, they changed the landing approach angle, and probably a billion other things. Do you even follow SpaceX bro?
I'd go out on a limb and say they will probably stick 8 out of the next 10 sea landings, and no less than 9 out of 10 RTL landings.
Which has more power: the hammer, or the anvil?
Hey, that's "ASDS Of Course I Still Love You" to you, bud!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Seawater and final impact speed are two good ones.
Seawater inside a booster makes refurbishing it MUCH harder. With parachutes, you can't control the attitude at which the booster hits the surface, and those rockets are designed to be very strong for vertical loading, but horizontal loading would destroy it... like a beer can, it can support a load at it's top, but not it's side.
Keep in mind that they have to fly with that fuel anyways... they need the margin in case of engine failure or other recoverable scenario. So all they've really done is add the weight of some landing legs, fins, a few other sundries, and some intelligent flight computers to relight the engine and bring it back down... it's not as inefficient as people are making it out to be.
Which has more power: the hammer, or the anvil?
Obviously now we have to see the recovery percentage that SpaceX can achieve, especially when they start landing Falcon Heavy on three barges, the one for the center booster being much farther downrange than the others. Seeing three land, two of them simultaneously, is going to be pretty amazing. If they can recover a lot of them, this completely changes the economics of space flight beyond the 30% discount SpaceX is quoting in the short term.
And don't forget that they are getting the Dragon back too, and Dragon 2 with its eventual ground-landing capability is expected to be reusable. Currently Dragon 1 lands in sea water, and the reuse they have so far is only of the pressure vessel, the capsule is stripped down to that and rebuilt.
Recovering the second stage is possible although not currently on the SpaceX roadmap. They would need to fly it with a heat shield.
Now, consider what it would take to land a Dragon on the moon and return. Not inconceivable, given Falcon Heavy and a few launches.
Bruce Perens.
There are two reasons that I've seen.
Third reason: Wind. In the post-launch press conference, Elon mentioned that the wind was significant during landing. (And may reach up to 50mph tomorrow on the way back to port.) So the rocket had to tilt somewhat into the wind to avoid being blown sideways relative to the landing pad, and only went vertical at the last moment. It also explains why the droneship maintains a slight tilt in some of the post-landing footage; this is to cancel out the considerable force of the prevailing wind.
Weeks of coding saves hours of planning.
60M is their entire rocket..... There are 3 parts to the rocket and their original (and still current) goal was for FULL re-usability. Since 33% of the rocket = 1/3, that completely matches up what they originally stated since you have to account for recovery, refurbish/inspection, and relaunch cost.
It's a long process and even SpaceX acknowledge early on the 2nd stage was more complex to recover and may not be possible. That said, the dragon capsule is slowly on it's way to re-usability so even if they don't accomplish that, a 50-60% cost reduction is still big considering they are currently the cheapest on the market.
It looked like pretty rough seas, too. The next step is that someone goes on the barge and welds shoes over the landing gear to hold it to the deck. There may also be something that fastens to the "octoweb", the frame that holds the engines at the bottom of the first stage.
Believe it or not, welding something to the steel is fast, and easy to un-do. You just cut it off with the same welding equipment, and use an angle grinder to remove the bead.
Bruce Perens.
Afaict they have attempted landings* on 6 flights of those two were successful.
Flight 14, failure due to grid fins ran out of hydralic fluid.
Flight 17, failure due to stuck valve
Flight 20, successful landing at the cape
Flight 21, failure due to landing leg issue
Flight 22, failure (and was expected to fail) due to coming in too fast due to a large payload.
Flight 23, successful landing on
So basically the devil is in the details. Each time a failure happens i'm sure they put a lot of effort into working out the details of what went wrong but what is not clear is how many iterations of failure they will have to go through before they get a reliable result.
One thing I would note is that they don't need 100% reliability. They just need sufficient reliablity to make the savings from reuse greater than the cost (payload reduction, landing location operations and repairs etc) of the landing,
* Defined here as attempting to land etiher a landing pad on land or a droneship. I don't count the drop in water tests as landing attempts.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
That's not really how rockets work. Sometimes a launch profile is compatible with secondary payloads, and so they sometimes do that. But often they're not, and so you can only launch to the one orbit. SpaceX doesn't control the satellite manufacturers operators: if the payload doesn't need the full payload, they can't just stick another satellite in there or tell them to make it bigger. If they could be putting additional payloads in the rocket to derive additional revenue, they would be. When they do the Orbcomm launches, they're launching lots of satellites at the same time, but then, those satellites all launch into very similar orbits.
Reusability on the first stage doesn't add terribly much weight anyhow: it takes a lot less fuel to decelerate a mostly empty stage than it does to accelerate the whole thing up to speed in the first place. It's also not a 1:1 relationship: 1 kilo of extra fuel does not subtract 1 kilo of mass from the potential payload. That would be true of the second stage, but not the first stage.
Since they can't really use that extra capacity anyhow, they might as well use it for cost savings, because reducing your costs is even better than increasing your revenue.