Hard Light Productions Forums
Off-Topic Discussion => General Discussion => Topic started by: Bryan See on January 25, 2016, 11:28:36 am
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That's great news for us to go to Mars and beyond, escaping certain doom for all of us.
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Dragon is doing very well, I see. :) For the record, I took my nick from the WC4 fighter (which I was always fond of flying) rather than from the capsule.
Anyway, it might not look like much (seeing as it was tethered the whole time), but it's actually a great milestone. Contrary to what KSP teaches us, throttling a rocket engine, especially with enough precision for hovering, is a huge engineering challenge. Dragon 2 is unique in that it has to throttle 8 engines, all of them to a great degree of precision and in sync with one another (Blue Origin did landing from hover before, but they had just one engine). It's important that this thing works right, since Dragon 2 is gonna be a manned capsule.
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That's pretty good news. hopefully that should make for better landings. Soyuz comes back down on land, but it's slowed by parachute, so there isn't much control, thus it has to land more or less in the middle of nowhere. being able to fly back to a proper spaceport is a useful feature.
A question, though, are those thrusters the same as those used for the launch escape system?
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That's pretty good news. hopefully that should make for better landings. Soyuz comes back down on land, but it's slowed by parachute, so there isn't much control, thus it has to land more or less in the middle of nowhere. being able to fly back to a proper spaceport is a useful feature.
A question, though, are those thrusters the same as those used for the launch escape system?
No. They are SuperDraco thrusters made by 3D printing. I would expect that Dragon 2's first manned test flight, which will see the 3D printed SuperDraco thrusters put through their paces, to take place in 2-3 years.
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Actually, they are. Those thrusters would be able to double as Dragon 2's LES, as well as the OMS thrusters (though they would most likely fire only two or perhaps four of them for OMS purposes). They use the same fuel/oxidizer mix as its RCS.
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Yeah. It's some kind of revolutionary and reusable, as well as ecologically clean, design. Good work, SpaceX. However, Blue Origin has beaten it with another reusable suborbital rocket.
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No, Bryan, they haven't. Origin has demonstrated they can fly, land and reuse the Sheppard vehicle, but it's a long way from Sheppard to what SpaceX is currently doing. Look at it this way: Sheppard is a very cool technology demonstrator and development vehicle. Falcon is a very cool tech demonstrator, development vehicle, and commercially viable launch platform.
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Also looking at the respective CEOs we see the importance of treating your employees like **** if you want to be part of the privatised space future.
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That seems to be a necessary ingredient, yes.
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Well it was an important part of pretty much every sci-fi private company, so why not? :D
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Out of curiosity, why was this "crucial"?
This doesn't seem especially important (or unimportant) compared with all of the other things it has to do.
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With a system like this, all tests are "crucial", really. As a part of the landing system, it's just as important as the question whether the capsule can hold pressure. IIRC, they want to dispense with the parachutes, so the rockets working right is rather vital for the crew.
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If the rockets is indeed usable, then why does it costs a little to produce such? Is it due to 3D printing?
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I hate the term 3D printing. It's become a catchall for self-contained fabrication and machining units, and that definition really fails to translate into the term "printing".
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If the rockets is indeed usable, then why does it costs a little to produce such? Is it due to 3D printing?
Probably more due to the fact that those are very simple rockets. SuperDraco is a pressure-fed engine, which means it doesn't have to bother with a turbopump. LVs have sometimes been described as "turbopump with a rocket attached" by engineers developing them, so dispensing with that makes the whole engine a lot simpler and cheaper. It's also hypergolic, unlike their earlier Kestrel, meaning that there is no ignition system to worry about. You're essentially left with an engine which consists of a regeneratively cooled chamber (a surprisingly simple element, even with that cooling method) and the fuel lines.
Indeed, that was the only reason they were able to "3D print" it. It's basically a combustion chamber and two pipes with valves, for delivering fuel and oxidizer. It might also have a heat exchanger and a repressurization system (running either helium or nitrogen through the engine cooling system in order to expand it. It's used to pressurize the propellant tanks), but that's it. They won't be using the same process for Merlin turbopumps anytime soon, I think.
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thus it has to land more or less in the middle of nowhere. being able to fly back to a proper spaceport is a useful feature.
It'll still land in the middle of nowhere in case a malfunction sends it careening away from the landing site.
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Yes, but that's only IF something goes wrong.
Every other capsule has either ditched in the ocean (mainly US) or in an uninhabited area (Russian/Chinese). If you can fly to a spaceport and land, you can get right out and they can put the spacecraft on a truck and drive it down the road to the hangar. if you land in the middle of nowhere, they have to send trucks and boats and helicopters and such to find you