SpaceX's Dragon poised to go orbital Elon Musk's SpaceX looks poised to send its Dragon capsule into orbit, following a successful static engine test of the Falcon 9 lifter. Static fire of the Falcon 9 engines. Pic: SpaceX After two aborted attempts, Saturday's two-second static fire of Falcon 9's nine liquid oxygen and kerosene-powered Merlin boosters …
Both Gemini and Apollo capsules were steerable during re-entry because their centre of mass had been offset in otrder to provide some the blunt-ended cone with some aerodynamic lift. By firing thrusters the astronaut was able to adjust the 'lift vector' and fly the capsule left and right to steer but also fly longer or shorter.
This is how later missions ended so close to the recovery ships that the splashdown could be filmed.
"I think this is the first time a capsule has used thrusters during descent for landing accuracy, but I could be wrong."
You're wrong. All lifting capsules use thruster burst to maneuver, although in *theory* a set of Control Moment Gyros could do the job you'd probably still need them for direction and velocity control during docking.
"Are we talking a genuine few hundred yards or a Ryanair few hundred yards, here?"
Well lifting capsule (that's ones with offset centres of gravity like Gemini and Apollo) could put down to within (IIRC) 0.6 of a nautical mile (1110m)
With better air models and sensors (and *much* faster on board processors) they should do *much* better. If they go with a parafoil parachute then within a runway width is possible (the plan for the X38 ).
Despite all the optimism, the State Dept. must still see access to space for world+dog as a frightening prospect. Imagine if anyone with enough dosh could orbit something over your country from half a world away. To date the major players have been governments who can be threatened/bribed as needed. Bumbling NASA has amply filled the role of Preventer of Space Services over the years. Potential disrupters such as Orbital Sciences have been neutralized by feeding them with official work to prevent them selling their technology on the open market.
Still, the dam must break eventually. Will SpaceX be allowed to succeed? Will financing suddenly dry up? Will "accidents" happen? So far two companies, OS and Sea Launch, have created launchers that threaten the status quo. Both have been carefully controlled. SpaceX will probably be allowed a certain number of launches, but the revolution is still a long way off.
"the State Dept. must still see access to space for world+dog as a frightening prospect."
it does. Stoked by a 100 yr old (and now thankfully diseased) old senator and the insanity that is ITAR,
"Imagine if anyone with enough dosh could orbit something over your country from half a world away."
Have been able to for some time. That sort of thinking (basically that *only* the US can launch substantial payloads because they know how had been dead for at least 20 years. Everywhere but in the US houses of parliament)
"Potential disrupters such as Orbital Sciences have been neutralized by feeding them with official work to prevent them selling their technology on the open market."
It's called the International Trafficking in Arms Regulations and both OSC and SpaceX have to abide by it as they are US corporations (and it applies to staff of foreign rocket builders who have US citizenship). If you want to be ITAR proof do not hire staff with US citizenship or use US sourced space hardware. Fortunately the US has kick started many such efforts.
"Potential disrupters such as Orbital Sciences have been neutralized by feeding them with official work to prevent them selling their technology on the open market."
The US government is *the* biggest launch customer in the world and OSC got their start launching DARPA payloads. The fact their rocket cost *doubled* in design *might* have something to do with the fact one of their key suppliers (Hercules ) is *also* a suppliers of most of their core parts (the solid fuel rocket stages).
One could speculate that OSC gets a "special" price for these which slides a fair sized chunk of cash out from under the nose of any US Gov auditors. That of course would be an outrageous suggestion as we know all US government con-tractors are companies of the *highest* ethical standing.
"Still, the dam must break eventually. Will SpaceX be allowed to succeed?"
I suspect Mr Musk plans deeply.
"Will financing suddenly dry up?"
Not likely. They've done 5 launches (including set up a total production line) for less than $250m. BTW OSC are asking for *another* $312m for a "Risk reduction" and *hope* their first actual supply flight *might* make it to the ISS by the end of 2012.
"Will "accidents" happen?"
Indeed the death of one of the key principles of the world first (and only) designed-for-cost hybrid rocket in a single vehicle car accident was inconvenient for his potential customers. Apparently an early victim of trying to use a mobile phone while DUI. Most regrettable.
"So far two companies, OS and Sea Launch, have created launchers that threaten the status quo. "
Not really. OSC was heavily dependent on govt launch business from day 1 and has about the *highest* $ per lb cost of *any* US launcher (with the *possible* exception of SpaceX *none* of which are cheap). Sea launch was *much* more interesting.More Russian with streamlined (relatively) launch crew.
The issue on launch costs is all about the standing army of people who babysit it (and the *much* large group that don't even *touch* it directly)
"but the revolution is still a long way off"
Agreed.
I'm sorry you dislike my style. I have written long posts and do try to break them up, part of which is the use of emphasis. My use of this on occasion may have been excessive (You definitely would not have liked my post on software for the DWP, some of whose software is incapable of lowercase text entry).
I think we'll have to disagree on this. I'm more concerned with your views of the facts I present or the opinions I hold.
What saddens me *most* is your inability to put your name on your criticism.
I can understand why people who criticise powerful and wealthy interests want anonymity.
But I'm neither.
My opinion of people always rises if they are prepared to identify themselves.
For a "Risk reduction" flight.
Translation
<cynical>
"sure we bid for the available money when Rocketplane Kistler failed but we didn't think we *could* design and build a new 2 stage launcher + capsule, mixing a totally new liquid 1st stage *and* new solid 2nd stage (*even* when we sub'd the design and build work out on the 1st stage to the former soviet union and got the 1st engines cheap off Aerojet cause RK couldn't come up with the cash *and* got the capsule design by mod'ing the European cargo carrier on the Shuttle) so can we have *another* bag more cash as we *promise* our vehicle will *never* be crew rated and in no way compete with NASA's current capsule plan no matter *how* dumb and expensive that is, pleasssssse"
</cynical>
I wish OSC *every* possible success. Competition is *always* good in technology but so far they've done *lots* of new building work on their launch pad (I think Spacex just found one that was about the right size first), refurbished a NASA test stand (thanks guys) and built a new assembly shed to go with it (given they are doing horizontal assembly I'd presume the building where they build Pegasus would be high enough but no one wants to move large chunks of solid rocket propellant (AKA high explosive) around the country too much.
Practically all solid rockets use a low-order propellant. There were a few developed, e.g. for 60's era ABMs/interceptors, but that's not what you're going to find on launch vehicles.
Still, it's nothing to play around with. Some of it will light up if you look at it funny on the wrong day. If the smoke doesn't kill you, the radiant energy will give you as nasty a "sunburn" as you can imagine.
"Practically all solid rockets use a low-order propellant."
Describing solid rocket propellant as "High explosive" was a bit excessive. I was thinking of the kind which drives ICBM's like Polaris and Trident and the Sprint ABM. The core of these double base propellants is a mixture of nitrocellulose (gun cotton) and nitroglycerin, both very much high explosives. The Trident motor added the explosive HMX into the mix.
I had forgotten that for civilian use they tend to use Ammonium Perchlorate with a rubber binder and a lot of Aluminum powder, like the Shuttle SRBs.
That said I'm not sure the difference in explosive potential makes *that* much difference in terms of the precautions that need to be taken.
AFAIK all solid rockets can also (under the wrong circumstances) undergo a "deflagration-to-detonation" transition. *Any* solid can go bang.
Solid propellants are great for weapon systems but I'm very wary of their use in either reusable or crew carrying vehicles.
I hope the best for Spacex Dragon launcher it's about time that the space program got a kick in pants. It been 40 years and man space has been morbit all this time but I wish they would find and use a better propulsion system than rockets which barely work and are tempermental but if this will break NASA strangle hold I am all for it.
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