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Russian Manned Space Vehicle May Land With Rockets
The Narrative Fallacy writes "Russia's next-generation manned space vehicle may be equipped with thrusters to perform a precision landing on its return to Earth. Previous manned missions have landed on Earth using a parachute or, in the case of space shuttles, a pair of wings. Combined with retractable landing legs and a re-usable thermal protection system, the new system promises to enable not only a safe return to Earth, but also the possibility of performing multiple space missions with the same crew capsule. The spacecraft will fire its engines at an altitude of just 600-800m, as the capsule is streaking toward Earth after re-entering the atmosphere at the end of its mission. After a vertical descent, the precision landing would be initiated at the altitude of 30m above the surface. Last July, Korolev-based RKK Energia released the first drawings of a multi-purpose transport ship, known as the Advanced Crew Transportation System (ACTS), which, at the time, Russia had hoped to develop in co-operation with Europe. 'It was explained to us how it was supposed to work and, I think, from the technical point of view, there is no doubt that this concept would work,' says Christian Bank, the leading designer of manned space systems at EADS-Astrium in Bremen, Germany. However, the design of the spacecraft's crew capsule had raised eyebrows in some quarters, as it lacked a parachute — instead sporting a cluster of 12 soft-landing rockets, burning solid propellant. Inside Russia, the idea apparently has many detractors. During the formal defense of the project, one high-ranking official skeptical of the rocket-cushioned approach to landing reportedly used an unprintable expletive to describe what was going to happen to crew members unlucky enough to encounter a rocket engine failure a few seconds before touchdown."
Of all the crap I've seen on /. I didn't realize we had unprintable expletives around here? Now, I'm curious - what could be so bad that it can't be printed on a /. page?!
If you can read this... 01110101 01110010 00100000 01100001 00100000 01100111 01100101 01100101 01101011
It's Russian, and Slashdot doesn't support the russian alphabet well?
That's so retro.
I am TheRaven on Soylent News
In other words, they must think that adding that extra fuel weight (for landing) is worth the extra fuel weight that is needed to launch the rockets into space. After all, the landing fuel will cost them a lot of extra weight. I don't know how much extra it would be, but it doesn't sound like a good idea.
Full Tilt
McDonnell-Douglas did this almost 20 years ago - the DC-X (http://en.wikipedia.org/wiki/DC-X), later known as the Delta Clipper.
It seems pretty inefficient to carry the fuel mass for the retro rocket braking all the way up out of the gravity well into orbit and then back down into the gravity well so you can use it in the last kilometer of the flight. There doesn't seem any way to stop at a gas station on the way down, but maybe they are planning on lifting the fuel to orbit on non-reusable tankers, which also seems inefficient. In something like this, inefficient equates to really fucking expensive.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
Let's see, how fast might the ship being going when the landing system kicks in? Falling from orbit to the ground is going to produce a lot of velocity to bleed off in apparently a very short time. The shuttle uses both atmospheric braking and S-turns to bleed off velocity and still lands pretty darn fast.
It sounds like this just falls without a chute. I'm not going to do the math, but even if it is subsonic at 800m, you are going to have to brake like mad at the end. 10G braking? 20G doesn't sound like it would be outlandish. OK, so it is a short period of time and with solid-fuel rockets it is just one pulse. But it sounds like it would be ohe heck of a pulse.
"Imagine, an expletive so vial it transcends language barriers."
I don't have to imagine it. The word you refer to is "Belgium".
If I were God, wouldn't I protect my churches from acts of me?
It's an urban legend.
This again? Let it die.
NASA didn't fund the pen at all.
When it was developed, BOTH the Russians and the US adopted it's use.
Before that, they BOTH used grease pencils, because broken graphite and flammable wood are loads of fun in space.
http://en.wikipedia.org/wiki/Space_pen#Uses_in_the_U.S._and_Russian_space_programs
-- i am jack's amusing sig file
In French Québec, we're lucky enough to combine all four.
And not just in your profanity!
The enemies of Democracy are
I think this will work. It's used extensively on giant robots in Japanese cartoons.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
The existing Soyuz TMA capsules also have "soft-landing rockets", they're used just at the point of touchdown to cushion the landing. Of course, the TMAs also have a parachute, so it's less of a problem if the landing rockets fail.
Interestingly, the very first Soyuz TMA had all kinds of other problems, but the landing-rocket part actually worked.
2*3*3*3*3*11*251
The energy to stop a falling box of people is nowhere near the same energy it takes to get it up to where it fell from when you're dealing with high speeds. Aerodynamic resistance is signficant even on a bicycle at 30mph, never mind a space reentry behicle.
The atmospheric drag does work both ways. But on the way up, a rocket presents an aerodynamically efficient profile - i.e pointy bit first. On the way down reentry vehicles go what you might call butt first, presenting the most aerodynamically *inefficient* profile possible.
Don't get me wrong, I'm all in favor of spaceships landing on a tail of fire, "the way God and Robert Heinlein intended!" But rocket-powered landings on Earth are a questionable engineering decision even when you get to reuse some of the liquid-fueled rocket engines that you already needed for liftoff and already wanted to recover intact. If you instead have to add extra weight to your upper stage for single-purpose solid rockets of lower ISP, it seems even more dubious.
And that's before you get into the issue of "solid rockets" and "precision". Even designing a liquid-fueled rocket with adequate throttle control for a gentle landing isn't easy. (It's like brain surgery! Or possibly like some other appropriate metaphor!) But at least throttling liquid fuel consumption rates is possible. Solid rockets basically have just three settings: "off", "on", and "kaboom".
Had a friend of mine that was Lithuanian. She told me that they had no curse words.
About the worst thing you could say to someone in Lithuanian was, translated to English: "I hope your rabbit gets mange!"
Scary words, those.