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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.
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.
Or the 1997 Japanese Space Hotel.. Or the 2016 Solaren space-based solar power array? Space attracts a fair number of snake-oil salesmen, and their true believers.
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?
Hmmm I don't think it'll work.
First, you'll probably need to stop the rocket at the surface of the water, it'll will have the time to gain a lot of momentum while it enter.
Second, the rocket will now slow down that much if it enter the water vertically, you'll probably have to figure a way to deploy a short of water parachute (which will add some weight).
Thirdly, those rocket are quite fragile so, even if the drag of the water will slow the rocket a bit, I'm quite sure it'll be damaged if it tip over and fall like in the last landing where the leg didn't lock.
Elok
Its development is still on a slow simmer, the company is still working on it, but it looks like they're trying to develop the SABRE engine for "commercial" (US Air Force and BAE Systems) purposes to raise capital for a push at developing SKYLON.
They've been promising us space hotels forever; did none of you read Charlie and the Great Space Elevator?? ;)
They can do a landing on solid ground (or at least they have done it once). Unfortunately, there is no solid ground in the right place for most flights
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!
That would require a much more precise landing. Moreover, the strongback which holds the Falcon 9 steady before launch wouldn't work here since that's dealing with very tiny amounts of being pushed in one direction or another, orders of magnitude less than what would occur during landing. The rocket is not designed to have a lot of pressure from one side like that, and making it so that it could would add a lot of mass.
The rocket is not designed to handle stress from all angles. Flopping into a net would entail coming down hard in a direction that it is not designed to handle stress. The primary advantage of a vertical landing is that most of the stress remains vertical just like when the rocket is being launched. Building it to handle other directions would require much more mass. They'll get this to work eventually, and this was a very difficult run anyways because the orbital profile required the rocket coming down from higher up, at a higher velocity and with less fuel to work with. Please be patient.
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.
The rocket stage is much like a soda can. Super thin alloy. It can only handle stress in the vertical direction. Therefore the answer is *no*.
Those arms aren't holding the rocket in place (except for the strongback on some launchers which retracts a half-hour or so before launch, typically used for launchers which are transported horizontally then raised into position), they're arms supporting various cables and hoses for supplying ground power, communications, fuel and pressurization. They retract at launch to pull out all the connectors and get them safely away from the vehicle.
Vehicles are usually held down by explosive bolts or retractable clamps at the very base of the vehicle, which ensure that thrust has built to a stable point before release (depending on the vehicle).
-- Alastair
Because it will basically never be cheaper than expendable rockets due to the massive R&D and construction costs, and by the time it was flying, it would be competing against other reusable rockets anyhow.
It's all about the fuel. On launches that leave enough spare fuel, they actually return the rocket all the way back to a landing pad at the launch site in Florida. They successfully landed the rocket once in that manner. But on launches that require more fuel (to put a heavier payload into a faster orbit), there isn't enough fuel leftover for the burn that would send the rocket back towards the launch site. As a result, they are limited to a relatively ballistic trajectory from the launch site, which means landing somewhere out to sea. The landing destination is actually pretty precise (the drone ship is trying its best to stay stationary, not move to meet the rocket), it's just that it's the only place they have enough fuel to get to.
The first stage of the rocket never reaches orbit: it's still going really really fast, but not orbital velocity. So after the second stage separates, left alone, the first stage would start falling down again downrange and crash into the ocean.
Normally, after separation, the first stage flips itself over and then does a boostback burn to kill the forward momentum, and give it enough momentium backwards to line up its trajectory back towards the launch site. Then later it does a deceleration burn to slow itself down to keep the atmosphere from ripping it apart. And then finally, it does a landing burn for the last segment to slow it to a stop.
On some missions, they don't have the fuel to do that full boostback burn, so they kill some of the forward momentum, but that's it.
Actually their one successful landing was from a launch in Florida, but they had enough fuel to return to the launch site.
"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.
Big hot rocket engines and nozzles crack when immersed in cold water.
Bruce Perens.
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.
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.
Today's vices may be tomorrow's virtues.
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?
Tracy Johnson
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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.
You can't just move the launches to California. The reason why the launches are happening in Florida is because there aren't people to the east of the launch site for hundreds of miles. If the launch was done instead at Vandenberg, the flight path would take the rocket over Santa Barbara and potentially Los Angeles, where not very many people would be happy if pieces of the rocket like what happened during the CRS-7 flight started to fall on their homes.
Moving the launch site to perhaps the Mojave Airport (which is even licensed by the FAA as a proper spaceport for some spaceflight activities) would still have this rocket arcing over Las Vegas and Phoenix and eventually over the whole south-eastern USA.
Russia gets away with launching their rockets in the middle of Asia in part because the flight path is similarly over almost completely unpopulated parts of the world (mostly Siberia and the steppe of Kazakhstan)... and the Soviet Union (when the launch site was built) didn't worry about pesky details like lawsuits from its citizens. The Russian government still doesn't care, and by the time rockets from Russia are heading over Alaska it isn't too big of a worry as the rockets are already in orbit.
In short, a flat plain or desert in the middle of the Atlantic Ocean would be nice, particularly if it had no people. Unfortunately that land without people doesn't exist.