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SpaceX's Latest Launch Successful, But Ends With a "Hard Landing" (theverge.com)
Eloking writes with this news from The Verge: SpaceX successfully launched its Falcon 9 rocket into space this afternoon, but — as expected — failed to land the vehicle on a drone ship at sea afterward. CEO Elon Musk said the rocket 'landed hard' on the drone ship. The mission requirements made a successful landing unlikely. This was SpaceX's fourth attempt to land the Falcon 9 post-launch on an autonomous drone ship floating in the ocean. All of the previous sea landings failed too, though the third attempt came very close. The company had low hopes of a successful landing from the start of this mission, since the rocket had to send a heavy satellite into a high orbit. That requires a lot of fuel for the launch itself, so there wasn't much fuel left for the rocket's return to Earth and powered landing.
It happened last night..
SpaceX and Marco Rubio are duking it out to see who wins "best management of the expectations game." Personally, I'm gonna give "third place win" the edge over "successful failure," but that's just me. Good hustle all around guys!
Just because you sold your soul to the devil that needn't make you a teetotaler. --The Devil and Daniel Webster
Boom!
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
Right now, both of the barges have horizontal thrusters that will keep the barges in 1 place. In that regard, it makes much easier for the craft to come down. However, the barges do not have vertical thrusters, so, they will pitch and roll in the same location. Without these, it is going to be impossible for these to land on the barge during heavy seas such as what was seen. On a calmer day, with say 1 m waves and under, the stages will do just fine.
I prefer the "u" in honour as it seems to be missing these days.
Would there be benefit in trying to land the rocket in a pool of fresh water (or even pure water or some other non-ionizing solution)?
It would at least be less corrosive than salt water, and if they get it out quickly maybe not significantly damaging at all?
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...wonder where SKYLON is? http://www.space.com/32112-how-skylon-space-plane-works-infographic.html
He will destroy us all!
It is not uncommon for rockets to be held in place by arms that fall to the side when it goes to launch. Why not have arms from the side rise up to grab the rocket landing on the barge?
Just let it flop into the net. Problem solved.
I have to wonder if there's a language this vodka-tainted gibberish could be translated into where it actually makes sense... Okay, probably not.
So their design allows them to send heavy loads into orbit but that requires so much fuel that they can't land it afterward.
So either don't launch things heavier than X, or increase the fuel capacity. It's not rocket sci... oh wait, it is!
The finished the marathon (launch very heavy satellite), they just failed their secondary goal of leading at least one mile of the race (landing on barge).
The use of superchilled liquid oxygen was a big step for them. Making the fuel denser allows them to put more fuel in the same volume.
I love Jesus, except for his foreign policy.
Can someone explain to me why they're using the drone ship as opposed to say an open flat plain or stretch of desert? It seems to me that adding in the complexity of rolling waves makes this a lot harder. Or, and maybe I'm answering my own question here, is it a lot harder to hit a specific target on land when coming down from LEO and thus the ship's mobility allows them to have a larger area to choose from for a landing?
I guess, if the primary goal of that person was simply to jump off of the Empire State building, with a safe landing just being a bonus, then I guess it works as an analogy.
"His jump off the Empire State Building was successful, but his secondary goal of landing safely was a disaster."
The Al-Qaeda terrorist successfully jumped off the Empire State Building, fired the RPG into Trump Tower killing Donald Trump, and failed to land successfully into the recovery net at the bottom when he knew he was going to be a martyr anyway.
Yeah, talking about moving goal posts to the level of stupidity.
The purpose of the flight was to deliver a communications satellite to geo-synchronous orbit. Your analogy here is sort of suggesting that actual objective wasn't accomplished.
How's that barge landing thing working out?
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Yeah, talking about moving goal posts to the level of stupidity.
The purpose of the flight was to deliver a communications satellite to geo-synchronous orbit. Your analogy here is sort of suggesting that actual objective wasn't accomplished.
So if landing one of these candles isn't an objective, why are they trying to do it?
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
It's an objective, but not a primary objective.
Primary objective is to put the satellite in the planned orbit. They accomplished this.
Secondary objective is to recover the rocket via a controlled landing. They did not accomplish this.
A secondary objective is, of course, secondary (to use a tautology). It's something that's nice to have accomplished, but even if it doesn't happen, the event isn't a failure.
If you want a famous analogy, take the mission that killed Osama Bin Laden. Primary objective was probably something like capture/kill Bin Laden. Secondary objectives was to capture others and bring them back for interrogation, as well as to recover documents.
The mission killed Bin Laden. But due to the loss of one of the copters, they weren't able to bring all the captives back. They accomplished their primary objective, but failed to fully carry out their secondary objectives.
Yet few would consider that mission as a failure.
FUCK YOU! Capra does not deserve to smell my shit!
FWIW large cruise ships don't have keels but use water balasts and engine pods for stabilization.
Falcon Heavy will benefit most from the reusable technology. It uses two Falcon 9 first stages as boosters. The flight profiles will allow the two boosters to land back at their landing pad. They also have the option of recovering the central on the drone ship which is harder but we can see that they are getting closer with each attempt.
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I postulate why? Isn't there enough land to land on?
Wasn't the original idea of ending up at sea was so they could soft-splash in the water?
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BT
The SES-9 re-entry really was ballistic. Only low-energy missions have the fuel to do a boostback burn, even lower energy if you want to return to launch site, and Falcon 9 Heavy can't return the center stage to launch site because it goes too far down-range. In general they need the barge to be where the rocket will come down, so that recovery does not impinge on mission fuel. A stationary platform is too containing, too expensive, and it only solves one problem: vertical motion. Vertical motion is not so big a problem that you have to build an entire artificial island mid-ocean, there are better ways to deal with it: the rocket can probably compensate for it.
Bruce Perens.
I'm not talking about boosting back to the starting point. Also SES-9 had less fuel than the original mission spec because Space X punted the satellite out a lot further than the original plan, it would be a prime candidate to remain a barge landing or just a rocket you don't even try to catch. Ideally it would be the xth launch for that particular first stage where the rocket cost was already well and truly covered.
Also one has to assume that rockets will get more powerful as they develop meaning a wider scope of landing locations given fuel is the cheap part. Google tells me that a deepwater oil platform costs about $650m for one on 3000m legs. SpaceX claims $57m per launch. If it halved that you need 20 launches to recover the cost.
As for compensating for it, the rocket is a big narrow tube. Any kind of swell will make it likely to tip over post landing. It would be really really annoying to have landed the rocket, shut everything down and then have it top over because of the sea swell.
I think SpaceX will sell a lot more geostationary transfer orbit missions now. They've shown that they can do it with a pretty heavy payload: 5300 kg, and they delivered 1300 km greater apogee than promised.
Your cost figure for building a recovery platform is for one of them. So, suppose that one would work for GTO on F9. To limit the delta-V needed for recovery, you'd probably need another for GTO on F9H center stage, because it gets a lot higher and further downrange, one for LEO insertions that can't return to landing site, one for polar orbits from Vandenberg, one for the 51.6 degree inclination of ISS. You'd also need to permanently man them and sustain the expense of offshore maintenance. And you'd continue to need barges and ships to transfer rockets from them. So, this probably increases the per-launch staff and infrastructure expense significantly when SpaceX is trying to reduce that.
The rocket is a big narrow tube, yes, but it's quite bottom-heavy at landing. LOX is in the upper tank, and you can see from the Orbcom recovery video that they vent the LOX the instant the rocket sets down, so that tank is empty. RP-1 is at the bottom of the lower tank, and then engines are under that. The engines are the heaviest part. The rest of the rocket is equivalent in thickness and weight to a soda can scaled up to that size. Pressurization is used to keep it rigid during flight. So, I think the chance of tipping over, if the legs actually work correctly, is lower than many folks estimate.
Bruce Perens.
I could be very wrong, but I thought polar launches had a potential land landing site. As for the multiple landing points, I wouldn't initially try to recover something like the most recent launch. Not enough fuel left for control and it is at the maximum end of the range spectrum. Also who knows about the center stage, I was only thinking about the first stage.
As for the differences between ISS launch and LEO etc, how much difference is there between them at the point of stage 1 separation? (I genuinely don't know). But my guess was it wasn't that huge. Not relative to the available altitude and speed.
As I said I could be completely wrong though.
Also, why are you permanently manning them, or even having that much maintenance? There isn't any moving bits. The 650m is for a working oil platform, I was just thinking a concrete slab on legs.
San Nicolas Island, California, is an offshore navy landing strip which I've speculated about but I've not seen any official word from SpaceX. It's about half the distance from LA that they positioned the barge, perhaps uncomfortably close to LA as far as range safety is concerned.
I am dubious that any platform in deep water stays in one piece without continuous attention. The British ones that have survived, more or less, since World War II are in shallow water and shielded from large waves.
Bruce Perens.