NASA tests rocket-disaster escape rocket NASA has announced a successful test of its "Max Launch Abort System" (MLAS), essentially a rocket ejector seat writ large and applied to an entire space capsule. The system is designed to let astronauts escape and parachute to safety in the event of a launcher stack crackup. The Max Launch Abort System tested at Wallops …
Used to be called the Launch Escape System in days of yore, i.e. during the Mercury and Apollo programs. MLAS is different in that the solid state rockets are integrated into the module rather than the old style bolt on missile with deflected thrust.
Paris cos she knows all about thrust, deflected or otherwise.
I see two immediate problems:
1. This looks quite heavy. That means the basic launch vehicle is going to need to be an awful lot bigger to compensate.
2. If the launch vehicle is designed to take off at pretty much the maximum G-force that the crew can withstand, they aren't going to enjoy the extra acceleration it will take for this to clear the expanding fireball behind them shortly after launch.
I don't understand the rationale behind this. With the old system, you could jettison the escape rocket as soon as it was clear that it was no longer necessary. With this system, it looks like you have to carry the useless rockets around with you until you are ready for re-entry (or at least finished with everything behind the crew module). Why carry the dead weight all the way up into orbit?
"If the launch vehicle is designed to take off at pretty much the maximum G-force that the crew can withstand, they aren't going to enjoy the extra acceleration it will take for this to clear the expanding fireball behind them shortly after launch."
Passing the commonly known 9 G limit won't instantly kill you. The problem is that you just can't maintain consciousness with over 9 Gs pulling down - that's bad for fighter jets because when you're pulling 9 Gs is usually the worst time to lose consciousness.
In this case, however, the crew is on their backs and the abort will only be a very brief jolt - and once it goes, the crew is just cargo. They don't need to be conscious. They just have to be in better shape than if they got blown up by a boned LV!
One of the Soyuz aborts IRL had a crew experience over TWENTY Gs due to the bad trajectory in which they had to bug out. They survived. It wasn't GOOD, but they lived, which is the point.
Ru - Thank you for pointing that out.
I think the Liquid VS Rocket debate will go to how stable the fuel is in space. Liquid Fuel can still be harmful in space unused and poses further risk (Think Apollo 11) Where solid fuel would be much more stable in that environment. Also probably safer to handle in general.
This article doesn't state so but my guess is they do re-enter with them attached, for sake of re-use. True, this poses a different danger. (it is space travel "Safe" is not exactly always easy, think lesser of two evils)
And as for "carrying around something you don't use" - someone needs to go back to physics class, as you are weightless (not accurate, but you know what I'm saying), once in orbit. Space on the craft I'm sure would be a premium, however, for the sake of launch safety, again, this is probably a weighted option.
Go go Gadget NASA
Someone else needs to go back to Physics class as well - and re-read the stuff about momentum / mass etc., if the object in space is twice as heavy as it needs to be, then it will take twice as much power to maneouvre it. That in turn requires more liquid fuel to be carried into space, requiring a consequently larger amount of power to get into space in the first place, asevery gram that is raised into orbit takes about a tonne of rocket fuel (I don't know the exact figures, but it is truly staggering proportion).
"And as for "carrying around something you don't use" - someone needs to go back to physics class, as you are weightless (not accurate, but you know what I'm saying),"
Oops...... will you be requiring a satchel or a nice adidas bag for that journey old geezer ?
Acceleration is in proportion to force and inverse proportion to mass.........in any environment, including zero G. Abort motors once in orbit are indeed useless, and do indeed have mass.
Sandwiches or school dinners ?
NASA (Need A Serious Ambition) are now reinventing something they perfected 40 years ago - the Apollo Escape Tower system.
Oh, that's right, the destroyed all the tools, plans and documentation because the Shuttle was All We'd Ever Need.
Paris, because she knows how to get things up.
READ about it !
The system IS jettisonned during launch (after the final stage) it is not carried around in space or connected during reentry...
Look at the construction image: you will see it adds a 6ft section to the rocket with 4 solid rocket boosters its a big hollow skirt not much extra mass!!
The escape rockets whether below (in this system) or above (as in previous) the crew module still only lift themselves, the crew module and nose fairing...
The entire vehicle = crew module and nose fairing and escape booster weigh in at a total of 20 tonnes, for the purpose of escape the nose fairing has to carry chutes but the crew module will land using its Normal decent chutes.. this was still the case with the old systems...
The questions that need to be asked are: what is the weight difference from the old system and the new? and what is the survivabuility improvement? ie is it worth it?
remember this escape method has never been used in NASA's entire history.
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