SpaceX set to try HOVER LANDING for re-usable rockets on March ISS mission In a potentially game-changing development for space travel, it has emerged that the booster rocket which will launch the next supply capsule to the International Space Station will attempt to make a soft hovering landing after it falls back to Earth. Mounting landing legs (~60 ft span) to Falcon 9 for next month's Space …
... I don't actually give a bugger if he/ they (Mr Musk et al) succeed or fail - though I'd much rather they succeeded :-).
I _do_ give much more of a (insert expletive of your choice here) that there are still folk around, like Mr Musk et al, who are willing to try, willing to fail - and willing to keep on bloody trying until they get there. For whatever insane, impossible, wonderful value of 'there' of they choose :-)).
If the boffins at SpaceX even come close on this next mission, the next obvious step is possibly a sea based platform, then try for land. Either way, even last mission's attempt was a great step forward.
Master the landing and we're looking at re-usable launch vehicles - and all this done with considerably less budget that the big aerospace outfits or ESA.
Ambitious, yes, but without a bit of guts, there's no glory.
"If the boffins at SpaceX even come close on this next mission, the next obvious step is possibly a sea based platform, then try for land."
I doubt it. Sea based platforms are expensive, whether custom-built or repurposed oil rigs. SeaLaunch won't want them within a thousand miles of Ocean Odyssey in case it goes bang, lands on the wrong bit of Odyssey, falls over when it lands or otherwise makes a mess of the place.
Drop it gently and precisely into the sea to prove you can, then move to a land site, which can amount to little more than a sodding great concrete pan in the middle of the desert with a road to truck it out - a hell of a lot cheaper to build than a sea platform and much less expensive to rebuild if you break it (how?), with nothing of value in the surrounding area if it all gets noisy!
One of SpaceX's cost cutting endeavours has been to launch from a pretty bare pad - roll the rocket out of a horizontal shed, tip it on end and light the blue touch paper. None of these massively expensive and very complex launch towers or service structures. They can pretty much go from anywhere with a bunker for Launch Control and a big fuel bowser, which makes logistics much simpler when you want to land a rocket on end in a wide open desert.
Of course that'll have to change when they go manned because the 'nauts will need to get up to the capsule at the pointy end (unless they load them in and then tip it up!?), but I don't see them building stuff like the Shuttle or Apollo service structures. Bare pads are cheap (relatively speaking) and they've designed the vehicles for them. No need for sea platforms and the like.
"Drop it gently and precisely into the sea to prove you can, then move to a land site, which can amount to little more than a sodding great concrete pan in the middle of the desert with a road to truck it out - a hell of a lot cheaper to build than a sea platform and much less expensive to rebuild if you break it (how?), with nothing of value in the surrounding area if it all gets noisy!"
Correct.
Which is what Spacex have had built for them at Space Port America in New Mexico, although that's more a flight test pad as they are planning to bring the stage(s) down to near the (but not at) the launch site, either Canaveral or Vandenberg.
"Of course that'll have to change when they go manned because the 'nauts will need to get up to the capsule at the pointy end..." - Psh! At the sheer levels of radical badassery demonstrated so far, I'd fully expect them to have the astronauts rapel down form choppers hovering above. Or jetpack straight to the top Iron Man style with a built-in mini-MMU. Or possibly just jump straight in from dirt bikes launched from a ramp, mid-flight - after all, 007 clearly demonstrated that sort of thing can be done...
I don't think they've solved the fuel issue, but I reckon they've spun the economics a different way.
Yes, their booster has to carry more fuel and weighs more / carries less payload in order to soft land, which costs. But then they won't have to build a whole new rocket, which might just cost less.
It's a bit if a gamble; a disposable rocket designed to the same engineering limitations would always be able to lift more payload to orbit. And if there's one thing satellite builders like it's having a bigger payload budget to work within. Just being able to put a year's extra maneuvering fuel on a big satellite might pay for the costs of a slightly more expensive but beefier launcher. These big TV and comms satellites are not cheap, yet cost no more to launch than their weight in concrete.
There are of course certain exceptions such as the main engines of the Space Shuttle, which were re-used although much of the rest of the launch stack (fuel tank and strap-on boosters)
The SRBs were re-used. They separated off before the vehicle achieved orbit, came back down to Earth (OK, ocean) by parachute, were collected, refurbished and reused.
The only part of the shuttle which wasn't reused was the external fuel tank.
All Elon has to do is copy the hover technology from his Iron Man suit and scale it up.
I do wish them luck though, this development has been a long time coming, I am quite surprised that NASA has not done more to achieve this ability given their skills at stretching relatively paltry budgets.
I am guessing there is a delicate balance between having enough fuel to set down gently with a small reserve and having so much left that the lifter could easily make an interesting hole in the ground.
Mr. Musk was not content to sit back and retire with his eBay profits, he has moved on and invested them into additional ventures. Whether you think any of his ventures have a chance of being a real commercial success or not, you have to respect the fact that he has taken on the established norms, particularly with spaceflight.
I have long mourned the numerous stalls experienced in the area of space exploration since the late 70's and early 80's. Mr. Musk has shaken up an industry that had become all too lethargic and has hopefully opened the door to future innovation. I look forward to seeing what comes next on this program. Hopefully many successes, but spectacular engineering failures are not only fun to look at, but can often teach us nearly as much as a success!
I raise a beer to SpaceX and all others challenging the all too stagnant status quo in many engineering disciplines!
succedes.
For him , he could have sat back and enjoyed his paypal millions and just sunk the lot into shares and investment schemes like nearly every other muilti-millionaire on the planet (which explains why the stock/property markets keep booming even when the rest of us are skint)
Instead , he's sunk money and time and money and more money into making a cheaper space launch system, even if it does'nt work, at least he has tried.
Either that or he hates the same phrase I despise "Thats the way we've always done it"........
which explains why the stock/property markets keep booming even when the rest of us are skint
That is not that.
These markets are booming because the money is easy (fuelled by newly printed money for bailouts, quantiative easing or to keep interest rates low, pyramiding through the fractional reserve banking system). The rest of us are "skint" because easy money fuels investments in things people do not really want nor need - generally high capital goods like skyscrapers and overpriced housing and cars, buildings full of cloud computing etc, which will lay fallow when the bubble bursts.
The fact that government keeps printing money, keeps people out of work with regulation and generally blows half of tax revenue on warfare (with a very large industrial tree feeding into it) and employs a fat percentage of the (overpaid) workforce at taxpayer's expense does not help at all.
"...he's sunk money and time and money and more money into making a cheaper space launch system, even if it does'nt work, at least he has tried."There is an apt saying here that goes something like:
"To make a millionare rocketlauncher businessman, first you start with a billionaire"The business has very few customers, and it is hard to amortise anything with the low quantity of launches and the extreme cost of doing anything, analysed to the nth degree.
I hope to see this succeed, even though that will initially negatively affect some of my customers (and therefore also potentially me). However as a whole, I expect to see it positively affect all of them in the long term.
Better I think. DC-X was a decent bit of kit but woefully underfunded. Grasshopper is bigger I believe, and the F9 bigger still.
But under the skin, they are always a fuel tank + engine + a few other bits and pieces. Not much 'new' technology there, just funding, better CAD/CFD, and better materials.
"But under the skin, they are always a fuel tank + engine + a few other bits and pieces. Not much 'new' technology there, just funding, better CAD/CFD, and better materials."
In the same way that a Leaf is like a Massarti.
DC-X goal was to demonstrate fast turnaround of LO2/LH2 engines. It succeeded.
It's top speed was Mach 3. It's shape was partly because the full size one was going to enter "sharp end first" and because keeping a long thin structure stable (even a bottom heavy one like a rocket stage) was considered very tough.
Which it is.
In that sense making the F9 1st stage reusable is much more ambitious, as it's likely to have to decellerate from about M13, with the minimal amount of fuel and TPS needed to ensure its survival and safe landing.
The truth neither you nor I know exactly what's under the skin because that's what Spacex has spent the time to find out.
Re-read my previous post and it read quite negative which was not my intention. I have been following SpaceX since the early days and am a BIG fan of the whole enterprise, and am very impressed with the progress they have made. My point was that the difference between DC-X and SpaceX isn't that great under the skin - they are fuel tanks with rockets on the bottom. But the details - that's where the difference will be made, and I cannot wait for these things to start flying (Esp. F9H with three returnable first stages will be quite something to watch).
But had DC-X had the funding it deserved, who knows where we would be now.
Every tonne of fuel that the rocket expends in a soft landing will require 11 tonnes of fuel to get it into orbit, and then more fuel for de-orbit, just so that it can be used in the soft landing. Why waste fuel for nothing? That tonne of soft landing fuel could be a tonne of payload in orbit.
If these guys have any sense, they will design an air-braked system that has at worst subsonic velocity coming in to land, then does most of its late braking using parachutes followed by a last-second rocket firing, just like Soyuz.
Why waste fuel for nothing?
Sure you need extra fuel that could be used to launch additional mass into orbit, but the reality of launching rockets is... Fuel is Cheap! it's the launch hardware that is not. If you spend a little extra on fuel to save a lot on hardware your ahead.
"f these guys have any sense, they will design an air-braked system that has at worst subsonic velocity coming in to land, then does most of its late braking using parachutes followed by a last-second rocket firing, just like Soyuz."
Funny you should say that....
In fact the stage is airbraked. The airstream howling into the nozzles of the 9 engines builds up plenty of back pressure and forms an air bubble acting as the re entry nose.
Actual engine thrust is only for initial deceleration burn and terminal thrust at the pad.
And Soyuz uses one shot solid rockets. It is also a capsule, not a stage.
You cannot imagine how grateful you're nothing to do with this design.
> Every tonne of fuel that the rocket expends in a soft landing will require 11 tonnes of fuel to get it into orbit, and then more fuel for de-orbit, just so that it can be used in the soft landing.
Wow, good thing the first stage doesn't go into orbit then. And good thing Daedalus doesn't design rockets.
(watch the videos, first stage separates well before orbital speed is reached)
And to think all these years I laughed at all those cheesy sci-fi flicks that show rockets backing down to the pad and landing on their tails.
And, just for the hell of it... here's a pretty wild early VTOL booster concept from the mid '60s.
I still suspect Skylon or that beamed propulsion research NASA are working on will be better in the long term as you would have only one stage, not a vehicle that breaks into 3 or more parts which all return separately.
But in the short to medium term this could be fantastic.
The only problem with this working is - will we get stuck with this 'old' Spacex technology for another 60 years rather than going on to make Skylon or laser beamed propulsion work?
Admittedly the NASA beamed technology spaceplane glides back to earth like the space shuttle, and both Skylon and the beamed propulsion vehicle are useless for landing on Mars, which is what Elon ultimately wants to do. They might be better technologies for earth however.
"I still suspect Skylon or that beamed propulsion research NASA are working on will be better in the long term as you would have only one stage, not a vehicle that breaks into 3 or more parts which all return separately."
The reason why SABRE/Skylon's funding has risen 3600x is not that it is single stage (and therefor easier to reuse).
The reusable F9 design (when it eventually appears) is expected to lose 60% of the F9 payload.
So either swallow the lower payload (presumably at a much lower price, but that is only at this point an "aspiration") or fly 3 payloads to do the same job.
Skylon is the same payload as a same sized 2 stage ELV.
That's important because the people who write the cheques work on the basis that GTOW --> cost.
Skylon lets you have your cake (SSTO from a runway potentially anywhere in the world, rather than a missile range) with no loss of payload.
As for beamed power that's a long way out for anything.
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