Elon Musk's 'Grasshopper' hover rocket scores another test success SpaceX, the radical upstart startup rocket firm helmed by PayPal hecamillionaire and geek visionary Elon Musk, has announced a further successful trial of its hovering "Grasshopper" test vehicle. According to the company: On Thursday, March 7, 2013, SpaceX’s Grasshopper doubled its highest leap to date to rise 24 stories …
The exhaust is actually the part that vectors. If you watch launch footage of the second stage in flight you can see it steer to perform attitude control. This way the main engine nozzle doesn't have to vector.
Here's a fantastic clip of the Space Shuttle main engine vectoring in a test fire: http://www.youtube.com/watch?v=BK0nG9aY6qU
Flame, because, you know.
The anti-ageing properties will come somewhat later, when the current readers are deceased and Space X has achieved something fractionally closer to the speed of light for its spacecraft. The "Australia" bit is just a sly reference to America's way of thinking of Texas as a dumping ground for convicts and dimwits.
Well, kudos to SpaceX. They put together a very smooth operation there.
Nice article too (weird about the URL but never mind...) but does anyone have any info on the number of 'hops' expected in 2013? And the expected milestone for each hop?
If I were one of the vice-presidents over at ULA, I'd be cashing in my stock options over the next few years...
Oooh, sneaky - Me likey!
Seriously though, ULA is more likely to lobby Congress harder to get the Air Force/NRO/DOD launch contracts booked through ULA that they are to find ways to make their launchers cheaper. While SpaceX does have a foot in the door, ULA is in the dominant position over there. I'd say that that ULA's strategy was to keep milking their cash-cow for as long as possible before being relegated to the dustbin of history.
At which point the various execs transfer back to Boeing/Lockheed etc and start overseeing next-gen air-to-air/surface-to-air missiles or other new aerospace projects which, like the F-35, will be highly likely to come in waaaay over budget. But those execs will still get their huge salaries and bonuses so no worries there.
The actual workers will get their pink slips because management was't interested in building stuff that was competitive on the open market but hey, did anyone think it would turn out any other way?
Grasshopper is doing the same sort of stuff as the DC-X did a few years ago, http://www.youtube.com/watch?v=wv9n9Casp1o for instance is still a bit ahead.
If they drop it and break it like NASA did with the DC-X though it will be a lot easier and quicker to replace so it should soon surpass earlier efforts.
Don't forget that that fuel tank is nearly empty, so the centre of gravity is way down low --- the the whole point of the system is to land spent first-stage boosters, using the engines they already have, using the dregs of the fuel they've already used. The fact that the stage itself is six storeys high (twice as big as the office building I work in!) is deceptive.
The liquid oxygen tank is at the top though so the weight distribution is vaguely dumb-bell shape.
It's actually easier to steer a rocket using vectored thrust if the weight is high up, if you've got a Fred Astaire style dancing cane, or failing that a small hammer, handy try balancing it on a finger both ways up and see which is easier to control.
It's a nice idea to be able to land your capsule. But I'm not sure it's a particularly efficient (i.e. low weight) solution. Maybe splashing in the ocean is not ideal, but the russians land theirs on land with parachutes. Maybe a small rocket just to cushion the last few feet and avoid a thump. Sure, you cannot get pinpoint accuracy, but recovering an undamaged capsule by helicopter or truck is a lot cheaper than carrying the extra fuel and rocket motors into space with you to enable you to land yourself.
It'd be pretty scary too coming in to land by rocket compared to parachutes. Presumably they have to kick in pretty late or you're going to waste a lot of fuel hovering down. Very little time to bail out if there is a misfire. Maybe the plan is for the astronauts to bail out and let the thing land itself... that would seem a lot safer.
But if they can get a reusable first stage (and even better, second stage too), that would really be key to making it cheaper, even if these parts cannot land themselves.
not really, the infrastructure to go collect & refurbish rockets is pretty hefty...
the ocean is a big place....
With a tail first soft landing, it is 100% intact, check the tyres, re-stack it etc... & reuse...
With parachute, its find it first, collect, test EVERY component to ensure nothing got damaged in the impact, then re-stack & reuse..
Don't underestimate the cost savings of NOT having 100 high paid guys standing round while you go on a rocket hunt...
But while this is all great, I still think Skylon & its successors are going to be the final key to opening space... but projects such as this will gain exposure and interest in investment, which will help others who don't have big multi-millionaires backing them
Er....I suggested landing on land by parachute, not the sea.
And I specifically mentioned a small rocket just to cushion last few feet. There is no reason for such a landing to require any more of a refurb than a full rocket powered descent. It can be just as soft.
But you're right about the rocket hunt though. That's the killer. If only boffins could devise some way to locate things anywhere on the earth accurately within seconds, perhaps using satellites and atomic clocks?
The short answer is: yes, it is. Because parachutes are big and heavy, and the rocket engines are free --- you've already used them to launch with! The only overheads are the avionics, the landing gear, and some dregs of fuel left in the tank from the launch. As the tank is now almost completely empty, it's a lot lighter than it looks in the video.
Also, don't forget that this is just for landing the first stage. It's never reaching orbit. SpaceX are *also* working on rocket-landing the Dragon capsule, using scaled up versions of the existing manoeuvring thrusters, for exactly the same reasons, but that's a totally different system.
"If parachutes are 'big and heavy', why is nobody jumping out of aeroplanes with rocket packs?"
Rocket packs are free if you're already in a rocket, because you...err, use the same ones you done launched with. Don't know too many folks who go skydiving from backpack rocket rigs...
The pilot lands by parachute after jettisoning the seat.
Now imagine the size/mass of a parachute necessary to recover the entire aircraft.
Not to mention that while the boosters don't go to orbit, they're moving pretty fast. They have to be slowed down.
Other options for returning boosters involve stub wings and runways - but that's extra weight too.
Brilliant!
They may not the first to do this, but it is still a very impressive step forward for them!
I've wondered for years why not just build each stage a LITTLE bigger and make it able to land...
since fuel is cheap relative to the rocket construction costs!
Oh, and just think, for planets with little or no atmosphere, this would be a great way to land... I.E. the moon!
Fuel is cheap, but it's heavy. Then you need extra fuel to lift that extra bit of fuel, then you need more fuel to lift that fuel ......
The real trick here isn't the balancing, that's just having a computer faster than a zx81 and engines that can tilt faster than the pendulum frequency of the stack. The trick is managing the fuel down to the last drop especially tricky when one of the fuels is cryogenic.
Some of the first efforts to use rocket braking were tried during WW2. It didn't quite work, partly because of the effects of the rocket blast on unprepared ground. The Soviet Union deployed a solution that involved a parachute, with the rocket pack between the payload and the parachute.
I've seen film of those WW2 tests. The rocket blast was excavating a crater, which was reflecting an asymmetric gas flow which flipped over the payload.
If SpaceX want to use the rocket landing approach, they have to be able to land on ordinary open ground, and they have to pretty accurately steer to a safe area. The Dragon capsule might be more stable, less likely to topple or flip, than a booster stage, but what size of target area will they need?
Water landings ain't easy, but the sea is big, and a lot more uniform. There are no trees and no sticking-up boulders.
Surely the point is that they return to a specific point and land there - which is entirely possible - rather than landing on 'ordinary open ground'. So you can make a landing pad that can withstand the blast. You can also put it in an area with no trees or boulders. A bit like the pad they are practising on....
> Some of the first efforts to use rocket braking were tried during WW2
Hold on.
What EXACTLY were people trying to rocket-brake during WW2? And how??
Germans were just barely managing to get A4s airborne and on trajectory. Have you seen the analog on-board computers for that (google up Hoelzer's Mischgerät). It was a pretty tall order, and Hoelzer recalls prussian generals and university profs giving him the laughing treatment. Luckily for him he didn't get the cybernetics-is-a-jewish-and-bourgeois-science treatment too. Doing the even more tricky braking manoeuver sounds dicey.
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