SpaceX rocket stage in 'soft landing'

 
Boost stage and legs The triangular features shown here are the legs that deploy just before landing

SpaceX says its recent experiment to return part of its Falcon-9 rocket back to Earth under control was a success.

The US company has confirmed that the first-stage of the vehicle launched from Cape Canaveral a week ago used its engines to slow its fall, deployed a set of legs and made a "soft landing".

For safety reasons, the touchdown was actually commanded to take place east of the Cape, far out at sea.

Nonetheless, the stage was vertical and had zero velocity on contact.

The company has video of the event - albeit of poor quality - that it plans to post on its website.

Extremely rough seas meant that a boat could not get to the scene for two days to try to salvage the stage before it sank.

Potentially, the experiment has enormous significance for the space industry.

The first-stage gets the rocket up off the pad

Traditionally, rockets have been expendable.

As a vehicle makes an ascent, it dumps propellant stages, which then fall to destruction, torn apart as they tumble end over end.

SpaceX believes if it can recover those stages and fly them again and again, the cost of access to space could be dramatically reduced.

"No-one has ever soft-landed a liquid-rocket boost-stage before," said SpaceX chief designer Elon Musk. "I think this bodes well for achieving reusability.

"What SpaceX has done thus far is evolutionary, not revolutionary. [But] if we can recover the stage intact and re-launch it, the potential is there for a truly revolutionary impact in space transport costs."

The first-stage of a Falcon-9 - the segment that gets the vehicle up off the pad - represents about 70% of a flight's $60m price tag.

Mr Musk told reporters that reusable stages could therefore lead to a hundred-fold improvement in the cost of access to space.

Demo This demonstrator shows what a returning stage with legs looks like

The company will now further refine its technology with the aim of making a return to dry land by the end of the year.

It needs to reduce the error on touchdown to a maximum of a mile. However, Mr Musk believes there is no reason why a return could not have the same accuracy as a helicopter, which comes to rest within feet of its intended landing location.

Discussions are already under way with the US Air Force, which runs the Cape Canaveral launch complex, to identify a suitable landing zone on the Florida coast.

The Friday 18 April experiment, which followed the successful launch of the Dragon cargo ship to the space station, was actually the second time SpaceX had tried a controlled return.

The first attempt in September last year saw the stage lose control late on, as propellant for the engines gradually spun up inside their tanks.

Atlas National security missions have been entrusted to ULA's Atlas rockets

Thrusters to correct the attitude of the stage were beefed up for this second experiment.

SpaceX also attached the landing legs for the first time. The telemetry confirmed these extended properly just prior to the stage touching water.

Reusability does not come without a penalty. The fuel needed for the manoeuvres and the weight of the landing gear affect the rocket's ultimate performance - the maximum payload it can carry to orbit. Mr Musk has previously calculated this penalty to be about 30%.

He also recognises that some of his customers may be uncomfortable flying their satellites on what amount to second-hand rockets.

"I think what we'll have to do is do a demonstration re-flight without an operational satellite onboard. And if that demonstration re-flight works, and some customers may want more than one - then that's the thing that would really ultimately convince them," he said.

Mr Musk was speaking to reporters at the National Press Club in Washington DC. He used the press conference to announce also that the company had filed a suit to protest the way rockets were being procured for national security missions, which include military spacecraft and spy satellites.

Thirty-six vehicles were recently ordered en bloc by the United States Air Force from United Launch Alliance, a joint venture between Boeing and Lockheed Martin.

Mr Musk said the absence of a competition "doesn't seem right", and claimed the use of ULA's Atlas rockets was a poor deal for US taxpayers.

"The ULA rockets are basically four times more expensive than ours. So this contract is costing the US taxpayer billions of dollars for no reason. And to add salt to the wound, the primary engine used is made in Russia."

 
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  • Comment number 24.

    All this user's posts have been removed.Why?

  • rate this
    +2

    Comment number 23.

    @21. Steven Wolfowitz

    Not such a good idea. The booster has a finite amount of lift which must exceed total craft mass at lift-off so the more mass you add to the first stage with the addition of complexity reduces the payload - the reason in the first place towards zero

  • rate this
    -4

    Comment number 22.

    Everything Musk has done has been at taxpayers expense - he is not an engineer - unless y'all count PayPal as a college - please dont buy an MBA from Musk - Tesla - the $100k toy battery car has not made a dime by GAAP profit standards in 10 years of production - it depends 100%
    on hydrocarbon taxes to keep it afloat - same/same SpaceX - it was not invented by Musk - he's a snakeoil salesman

  • rate this
    0

    Comment number 21.

    Great progressive steps achieved. Perhaps rotating 'helicopter' blades could be fitted in the nozecone deployable for landing approach to improve vertical stability and direction to accurate landing point and 'softness' of touchdown.

  • rate this
    +2

    Comment number 20.

    @3. sengmand

    "he should get the Nobel Prize"
    I agree but only after we get some way there. I would hate another devaluation of the prize as it was by giving it to Obama just for being elected - he as not done anything else to deserve it since. Or the EU that got it for god knows what

  • rate this
    -12

    Comment number 19.

    Everything Musk has done has been at taxpayers expense - he is not an engineer - unless y'all count PayPal as a college - please dont buy an MBA from Musk - Tesla - the $100k battery toy car has not made a dime by GAAP profit standards in 10 years of production - it relies heavily on hydrocarbon tax rebates to keep it from sinking - the same with SpaceX
    It was not invented by Musk - he's a hoax

  • rate this
    +2

    Comment number 18.

    #15 kevin "What happened to the Delta Clipper?.."

    The prototype crashed - but the real answer is politics and stupidity. In a way the Falcon 9 is now the descendant of the clipper.

    TSQ : What happened to .. the Shuttle replacement? politics and stupidity, NERVA? politics and stupidity, Constellation? politics and stupidity, the original project Orion? ... etc etc etc.. you get the picture.

  • rate this
    +3

    Comment number 17.

    This is a very impressive achievement. The 30% extra weight cost is not surprising given the method used for recovery, and given that this is a first stage is not so important. The value of the recovered stage should still massively exceed the extra cost.
    Lower weight penalties might be achievable with other methods like parachutes but they are more difficult still and more complex. Great Job.

  • rate this
    +5

    Comment number 16.

    The Space Programs should continue to help with discovery & understanding Evolution.

    The requirement of fossil fuels are the problem as they take up so much volume, If nuclear fuel could be harnessed into fuelling rockets, cost & material wastage could be reduced.

    Strange how the UK pays China Overseas Aid and yet China has a huge space program & one of the largest economies in the world

  • rate this
    0

    Comment number 15.

    What happened to the Delta Clipper?Too complicated and expensive.The reason to go into space is for the hell of it and divert money and engineers from nuclear weapons to space technologies.
    Both run due to tax payers money or government contracts so its a no brainer when spending money on space.

  • rate this
    0

    Comment number 14.

    Time to bring out the monkeys and strap 'em up. Bon voyage Albert II

  • rate this
    +5

    Comment number 13.

    @11. Entropic man,
    I seriously doubt we'll run out of metals for use on Earth,. what with recycling and new mining techniques.
    As for large scale high strength infrastructure,.. I suspect it will be largely centered around carbon based materials rather than alloys from platinum group metals that would make asteroids interesting.
    Space based resources will likely be mined for use in space.

  • rate this
    +10

    Comment number 12.

    To date the most credible reusable SSTO concept by far appears to be Skylon with it's SABRE engine.

  • rate this
    +3

    Comment number 11.

    Ander

    There is a solar system's worth of resources out there. The trick will be to get over the hump and build the space infrastructure to harvest them before our terrestrial resources run out. Anything which reduces launch costs is a step in that direction.

  • rate this
    +2

    Comment number 10.

    As the paycheck writer, he gets to call himself whatever he likes. Likely the team he's paying to do the hard work have enough "suggestion" filters in place that the design still works when he leaves.

    But a 30% payload weight penalty... ouch...

  • rate this
    0

    Comment number 9.

    This is excellent progress because it reduces the launch cost from $4300 per kg to $1800 per kg. But it's still twice as expensive as Skylon is designed to be and so Elon Musk must achieve his goal of complete reusability to compete with Skylon, when Skylon comes into service. And making the second stage reusable is going to be very difficult indeed.

  • rate this
    +2

    Comment number 8.

    Full reusability is the first step to making space truly accessible to all. It is often completely ignored how much we exploit space already when only nation states & corporations can afford to launch payloads. Imagine when small institutions gain ready access to low earth orbit while nation states & corporations move onto finally being able to access other planets & asteroids!

  • rate this
    +1

    Comment number 7.

    I looked at a video on thursday on the spaceX website showing a launch, the rocket getting to 325metres then descending still in an upright attitude back onto the launch pad. really amazing. Needs a lot of testing before it will launch an important payload. But if 2nd and 3rd launches go well and the price is right, they will be able to sell this to those that matter. Our views don't matter

  • rate this
    -11

    Comment number 6.

    Sengmand, you're hallucinating. Musk, if lucky, will make a few buck on supplying the useless ISS with groceries. Until the first accident to which his 9-engine launcher is prone To the benefit of everyone? Who exactly? Move to the stars? Name one. Musk will harness the power of the Sun? How so?
    Where do these people come from?

  • rate this
    +1

    Comment number 5.

    Confidence is that feeling you get just before you understand the problem.

 

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