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I smell mechjeb in this one.


AngelLestat

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They are testing out the feasibility of reusing their engines as opposed to say, using parachutes to land, the actual craft is a two stage to orbit.

What is wrong with parachutes? Unless the weight of the engines and fuel somehow weighs less than the paracutes, I don't see the point in swapping them out.

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What is wrong with parachutes? Unless the weight of the engines and fuel somehow weighs less than the paracutes, I don't see the point in swapping them out.

With engines they can not only land softer but are able to choose where they land, therefore you save money not having to fish them out of the ocean.

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With engines they can not only land softer but are able to choose where they land, therefore you save money not having to fish them out of the ocean.

And since the engine is already being used to launch the craft, you really can't count its weight against the cost of this style of recovery. As for the fuel, the fuel will weigh less than the parachutes.

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It's a technology demonstrator. Eventually, they hope to be able to do this:

This looks like a good idea up until the manned stage goes to land because, and could be wrong, I didnt see any parachute backups, one good engine hiccup and bye bye crew.

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And since the engine is already being used to launch the craft, you really can't count its weight against the cost of this style of recovery. As for the fuel, the fuel will weigh less than the parachutes.

Yeah, and i want to add something.

First we know that the 3 parachutes that we need to brake something like that are really big, and that is not enoght to land on land. So we need to add the fuel of the helicopter who recover the astronauts and the capsule.

The parachutes can be damage in the re-entry, or the armospheric conditions can also be a problem.

And we only need the amount of fuel to brake the capsule from 70 m/s (terminal velocitie) to 0 m/s

So... is a good idea if one takes into account all costs from both systems.

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This looks like a good idea up until the manned stage goes to land because, and could be wrong, I didnt see any parachute backups, one good engine hiccup and bye bye crew.

...same could be said for one good parachute hiccup. By the time any potential engine hiccup could occur, it's too low for backup chutes anyway.

Damned impressive vid. That's some serious landing precision by a computer there. Wonder why the tips of the gear are smoking?

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This looks like a good idea up until the manned stage goes to land because, and could be wrong, I didnt see any parachute backups, one good engine hiccup and bye bye crew.

Probably simpler from an engineering perspective to fit the hatch with explosive bolts and issue individual parachutes to the crew.

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I suspect it has *something* to do with the giant blowtorch they're mounted next to, and plume of hot has they're flying through on descent.

Yeah, or - as much as I remember - it's actually 4 small draco thrusters that are used for micro-correction burns to keep the craft stable

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And since the engine is already being used to launch the craft, you really can't count its weight against the cost of this style of recovery. As for the fuel, the fuel will weigh less than the parachutes.

Somebody said that they mainly use the fuel reserve to land, extra fuel if something goes wrong like losing an engine. Add that it don't cost so much to land, rocket is only moving at terminal speed perhaps 400 km/h.

Main downside of parachutes is that the landing is harder and you get an horizontal speed unless its perfectly calm and this will topple the rocket.

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...same could be said for one good parachute hiccup. By the time any potential engine hiccup could occur, it's too low for backup chutes anyway.

Damned impressive vid. That's some serious landing precision by a computer there. Wonder why the tips of the gear are smoking?

So they will not backup parachutes on the pod? Depending on design you don't need to be that high for parachutes to work, yes if engines dies 50 meter over ground you are toast but this would be an pretty unlikely failure.

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Right! Off to build that!

That may be a bit tough to do. You'll need to land that first stage fast. The second stage will soon drop back into the atmosphere and disappear once it hits 20,000 meters. The video they are doing has many things happening at once.

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Now they should do the "Up-Goer Five" challenge ;-p

From what I've read, the fuel used up returning the first stage will be substantial. SpaceX's next Falcon 9 launch will be an enlarged v1.1 to carry the extra fuel for that and they'll be flying the first stage down to a simulated 'landing' at the ocean surface (I mean, they were going to throw the thing away in any case, so why not have some fun with it >:-)

In operation, it seems they'll be making a 'turn around' burn at altitude to land the first stage back at the same launch-pad. That's very fuel intensive and I think they said something about a higher payload in "expendable mode".

The fuel will definitely weight more then a set of chutes, but SpaceX is rightly more concerned with economics then with fuel or weight. Fuel cost is insignificant in the space launch business compared to vehicle and operation costs. Landing with chutes means a water recovery, damage to the stage from impact, water; lot's of expense there. Even if they have to build a bigger rocket and burn more fuel, SpaceX will be laughing if they can bring a pristine stage right back to the pad it launched off.

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To those saying there's no parachutes on the "crewed module", the dragon spacecraft is an unmanned vehicule and no, it does not have any parachutes.

The projected Dragonrider variant however, will do his first test flight this year or next year IIRC, and will come with an emergency parachute in case the engines fail.

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Damned impressive vid. That's some serious landing precision by a computer there.

Yep! Imagine what a mess it would be with a sensor installed incorrectly though. Call me old-fashioned but I'd really prefer a flesh and blood pilot at the controls if I were to be a passenger on one of those.

Wonder why the tips of the gear are smoking?
Haha! Yeah, those legs are going to need a new paintjob. :P

I went to an interesting bonfire out on Padre Island a few years back. Our genius hosts lit ~40 wooden pallets all at once. The radiant heat was too much to handle at anything less than 40 feet and bubbled the paint on car bumpers ~20 feet away. Imagine what the radiant heat coming off that exhaust plume must be like for those poor lander legs.

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