Rockets launching over land for reuseability

[legoclone09]

I am wondering why NASA can't launch from somewhere at the westernmost end of the Mojave desert or something, and ditch stages to where they won't and can't hit anything because there is next to nothing there. It would allow reuse of rocket stages, cheaper recovery fees, and not impede sea trade. Of course airlines might get in the way, and other things. Can somebody tell me why NASA/JPL/SpaceX/any rocket company in America can't do this? Also if this should be moved, please move it.

[Kryten]

Because just dumping rockets over land doesn't get you anywhere closer to reusability? It just gives you a bunch of half-crushed rocket stages.

[Findthepin1]

If you're on a flight from San Francisco or Los Angeles to just about every major city on the US East Coast, you have to go over the Mojave.

[Mitchz95]

Recovering the spent stages isn't really the problem, it's recovering them intact. If it's so banged up from the landing that it can't be reused, there's no real point recovering it at all. Ditching them in the ocean where they won't damage anything is the most sensible answer.

EDIT: Ninja'd.

[Motokid600]

Itd have to be a propulsive landing like the F9. I too always wondered this, but I guess a simple answer is just too much red tape.

Parachutes would absolutely never be able to land a booster intact on land. If the shuttle SRBs had hit land they would've been crushed like a soda can.

[GeneralVeers]

Also consider that average folks are extremely paranoid of anything with the word "radiation" in it (think RTG's), and they want nothing to do with anything that can crash, explode, and scatter radioactive anything anywhere. Whereas they think "ocean equals safe".

[legoclone09]

Makes sense, typical paranoid people . I guess this won't work.

[Kryten]

You don't have to paranoid to not want rockets dropped over populated areas, and it has nothing to do with radioactivity. Most rocket fuels are pretty nasty.

[TrainEngie]

If you're on a flight from San Francisco or Los Angeles to just about every major city on the US East Coast, you have to go over the Mojave.

A rocket might hit a plane?

You don't have to paranoid to not want rockets dropped over populated areas, and it has nothing to do with radioactivity. Most rocket fuels are pretty nasty.

Just the thought of a giant falling tube is enough to scare people.

Also consider that average folks are extremely paranoid of anything with the word "radiation" in it (think RTG's), and they want nothing to do with anything that can crash, explode, and scatter radioactive anything anywhere. Whereas they think "ocean equals safe".

Precisely. Thus, giant island of trash happens.

Well, it might have one benefit: recycling rocket metal. Salt does nasty things to rockets... but the drawbacks outweigh the benefits, so... ocean's the way to go.

[magnemoe]

Itd have to be a propulsive landing like the F9. I too always wondered this, but I guess a simple answer is just too much red tape.

Parachutes would absolutely never be able to land a booster intact on land. If the shuttle SRBs had hit land they would've been crushed like a soda can.

The F9 solution should be possible its however not very easy, on the other hand having an large landing area instead of an barge will make it easier, you don't have to worry about position outside some hundred meters, just to kill speed and stay upright.

And you are right about parrashutes, even the small Russian pods need braking rockets and its still more like an crash than an landing.

Russia and China has an benefit here in that they launch over land, you can also avoid most of the boost-back issue, just put the landing pad downrange.

Another nice launch position would be south east asia as you launch over sea and close to equator but it should be possible to land on islands, added benefit is that its easy to bring stage back with boat.

[legoclone09]

What I mean is have a bunch of chutes to slow it down then a re-ignitable center engine like the Falcon 9, and land safely for refurbishment. And thank you all for taking the time to respond.

[magnemoe]

What I mean is have a bunch of chutes to slow it down then a re-ignitable center engine like the Falcon 9, and land safely for refurbishment. And thank you all for taking the time to respond.

Problem is that wind give you vertical speed unlike in KSP so you would have to cut the chutes and kill the vertical speed anyway before landing.

Your terminal speed is also pretty low, think the huge landing legs on Falcon 9 give lots of drag.

[YNM]

@ magnemoe : probably you meant lateral speed, as vertically, rockets have a fairly small cross-section.

@ OP : Well, I guess it depends on whether americans can accept if suddenly their house are, uh... hit by spent stages, like in china, or their crop fields burned, like in kazakhstan.

[Nibb31]

Launch sites are typically located near the ocean so that spent rocket stages don't fall down on populated areas. If something goes wrong, they can just blow up the rocket.

In Russia and China, launch sites are inland, and the rocket stages fall in the middle of steppes or desert areas. Occasionally on people's farms or villages.

What I mean is have a bunch of chutes to slow it down then a re-ignitable center engine like the Falcon 9, and land safely for refurbishment. And thank you all for taking the time to respond.

Nobody has managed to retreive a spent rocket stage, therefore nobody (in the US) has a reason to build a new launch pad inland. Launch sites are expensive. And even if SpaceX does manage to recover their first stages, they will be launching over the ocean and boost their way back to land, because failures do happen and nobody wants rocket stages and rocket fuel falling on their house (and SpaceX doesn't want the liability either).

Secondly, parachutes are heavy. Rocket stages are heavy. So to land a rocket stage on parachutes requires the largest and heaviest parachutes ever (like those used on the Shuttle SRBs), which makes them the most expensive parachutes ever. There is no reason to recover spent stages if it is not economical. Parachutes take a heavy bite into your payload fraction and your costs.

Finally, first stage engines aren't usually restartable. The Merlin is the first one. Engines are expensive to design, so again, it's cheaper to operate a disposable booster with an old engine design than to design a whole new vehicle.

Reusability is coming, but the reason it's not here is because it isn't economical at current flight rates and there is no actual proof that it ever will be, unless we suddenly discover new business opportunities that justify increasing flight rates.

Edited November 5, 2015 by Nibb31

[GeneralVeers]

You don't have to paranoid to not want rockets dropped over populated areas, and it has nothing to do with radioactivity.

People like us know that. The common folk don't. They think along the lines of "hey, the food processing plant is irradiating my food! THEY'RE MAKING MY FOOD RADIOACTIVE!!" They don't (and can't) understand that irradiating things (well, unless you irradiate with neutrons.....) doesn't make them radioactive--it makes them sterile so you don't get listeria from eating them. There's all kinds of ways ordinary folks misunderstand radiation. Probably comes from people watching too many movies where radiation causes ordinary creatures to turn into mutated horrors composed almost entirely of teeth.

[Van Disaster]

What I mean is have a bunch of chutes to slow it down then a re-ignitable center engine like the Falcon 9, and land safely for refurbishment. And thank you all for taking the time to respond.

The reason F9 isn't using parachutes already is because they'd take a bigger bite out of the payload than just leaving enough fuel for a propulsive descent - plus yet another system.

As for rockets over land, rockets are full of horrendous things. Planes are too, mind you ( aircraft hydraulic fluid is not nice stuff, afaik ).

[Kryten]

People like us know that. The common folk don't. They think along the lines of "hey, the food processing plant is irradiating my food! THEY'RE MAKING MY FOOD RADIOACTIVE!!" They don't (and can't) understand that irradiating things (well, unless you irradiate with neutrons.....) doesn't make them radioactive--it makes them sterile so you don't get listeria from eating them. There's all kinds of ways ordinary folks misunderstand radiation. Probably comes from people watching too many movies where radiation causes ordinary creatures to turn into mutated horrors composed almost entirely of teeth.

The only case I've ever seen of anyone connecting rocket debris with radiation fears is you, right now.

And of course even if you manage to land all of your rocket stages perfectly, overland launch still means dropping payload fairings and potentially boosters inland. So you still get stuff like this;

(Insert rant about how the owner of that has nothing to complain about because there's no radiation hazard)

Edited November 5, 2015 by Kryten

[magnemoe]

@ magnemoe : probably you meant lateral speed, as vertically, rockets have a fairly small cross-section.

@ OP : Well, I guess it depends on whether americans can accept if suddenly their house are, uh... hit by spent stages, like in china, or their crop fields burned, like in kazakhstan.

Yes, horizontal speed. the purpose of an parachute is to reduce vertical speed

None would build an launchpad inland today unless forced of geographical reasons like Russia. Both Russia and China probably put them inland of security reasons too back in the cold war then they was communist dictatorships. Coast would make then easy to spy on or destroy/ interrupt.

Southern part of China would be an better location and over sea.

You also do not want to launch over other countries.

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The only case I've ever seen of anyone connecting rocket debris with radiation fears is you, right now.

And of course even if you manage to land all of your rocket stages perfectly, overland launch still means dropping payload fairings and potentially boosters inland. So you still get stuff like this;

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=37977.0;attach=1071198;image

(Insert rant about how the owner of that has nothing to complete about because there's no radiation hazard)

More an issue is that the fuel and oxidizer in Russian rockets are very toxic and that people scavenge the crashed stages even if they don't hit any they are still dangerous.

[fredinno]

I am wondering why NASA can't launch from somewhere at the westernmost end of the Mojave desert or something, and ditch stages to where they won't and can't hit anything because there is next to nothing there. It would allow reuse of rocket stages, cheaper recovery fees, and not impede sea trade. Of course airlines might get in the way, and other things. Can somebody tell me why NASA/JPL/SpaceX/any rocket company in America can't do this? Also if this should be moved, please move it.

Actually, Kistler Aerospace wanted to do this, so they could recover stages by parachute and airbag.

Kistler went under a while ago.

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Because just dumping rockets over land doesn't get you anywhere closer to reusability? It just gives you a bunch of half-crushed rocket stages.

I think he means that parachute is used to slow the stages down before hitting the ground.

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Problem is that wind give you vertical speed unlike in KSP so you would have to cut the chutes and kill the vertical speed anyway before landing.

Your terminal speed is also pretty low, think the huge landing legs on Falcon 9 give lots of drag.

It would help stabilize the rocket for the final powered landing- and you could use airbags for the final portion.

I wonder if Parafoil would help increase locational accuracy?

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Launch sites are typically located near the ocean so that spent rocket stages don't fall down on populated areas. If something goes wrong, they can just blow up the rocket.

In Russia and China, launch sites are inland, and the rocket stages fall in the middle of steppes or desert areas. Occasionally on people's farms or villages.

Nobody has managed to retreive a spent rocket stage, therefore nobody (in the US) has a reason to build a new launch pad inland. Launch sites are expensive. And even if SpaceX does manage to recover their first stages, they will be launching over the ocean and boost their way back to land, because failures do happen and nobody wants rocket stages and rocket fuel falling on their house (and SpaceX doesn't want the liability either).

Secondly, parachutes are heavy. Rocket stages are heavy. So to land a rocket stage on parachutes requires the largest and heaviest parachutes ever (like those used on the Shuttle SRBs), which makes them the most expensive parachutes ever. There is no reason to recover spent stages if it is not economical. Parachutes take a heavy bite into your payload fraction and your costs.

Finally, first stage engines aren't usually restartable. The Merlin is the first one. Engines are expensive to design, so again, it's cheaper to operate a disposable booster with an old engine design than to design a whole new vehicle.

Reusability is coming, but the reason it's not here is because it isn't economical at current flight rates and there is no actual proof that it ever will be, unless we suddenly discover new business opportunities that justify increasing flight rates.

Yes chutes are heavy, but more heavy than tons and tons of rocket fuel to land, meaning a (much) larger, less economical rocket (and more expensive due to more insulation, tanking, engines, etc) for the same payload? I don't think so.

Well, making engines restartable- is that really so difficult?

I agree reusability is a pain.

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People like us know that. The common folk don't. They think along the lines of "hey, the food processing plant is irradiating my food! THEY'RE MAKING MY FOOD RADIOACTIVE!!" They don't (and can't) understand that irradiating things (well, unless you irradiate with neutrons.....) doesn't make them radioactive--it makes them sterile so you don't get listeria from eating them. There's all kinds of ways ordinary folks misunderstand radiation. Probably comes from people watching too many movies where radiation causes ordinary creatures to turn into mutated horrors composed almost entirely of teeth.

Never mind that 40% of the radiation you are exposed to comes from within you.

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Also consider that average folks are extremely paranoid of anything with the word "radiation" in it (think RTG's), and they want nothing to do with anything that can crash, explode, and scatter radioactive anything anywhere. Whereas they think "ocean equals safe".

Rockets aren't radioactive.

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You don't have to paranoid to not want rockets dropped over populated areas, and it has nothing to do with radioactivity. Most rocket fuels are pretty nasty.

Well, rockets are being moved towards soild fuel, RP-1 LOX, H2 LOX, and CH4 LOX fuels, and the gaseous cryogenic fuels probably can be ejected automatically before crashing to prevent explosions.

[Nibb31]

Yes chutes are heavy, but more heavy than tons and tons of rocket fuel to land, meaning a (much) larger, less economical rocket (and more expensive due to more insulation, tanking, engines, etc) for the same payload? I don't think so.

Actually, yes. Which is why SpaceX doesn't use parachutes. The Shuttle SRB parachutes and deployment systems weighed about 4 tons for each SRB. That's nearly 8 tons of wasted payload, and all that for a pretty hard splashdown.

Well, making engines restartable- is that really so difficult?

Most first stage engines are started or primed or ignited with ground support equipment. Air starting requires a major redesign of the engine where everything you need to start the engine is integrated into the engine.

[GeneralVeers]

Never mind that 40% of the radiation you are exposed to comes from within you.

Which is one more thing average folks don't know.

Rockets aren't radioactive.

Same as above. People see news articles about radiothermal generators on spacecraft, and they generalize. They are already thinking "radioactive = dangerous", then they see something mentioning radiation on spacecraft, and they think a spaceship crash could poison an entire continent. Which it can't.

You're arguing with me about things I see other people around me doing all the time. I know it happens because I see it happen. I see people have panic attacks about radiation on spacecraft whenever I get in a chat about space (which is, as you can guess, a lot). It's not only RTG's that worry average people, sometimes they worry about the fact that the spacecraft "was exposed to intense solar radiation" and therefore the craft shouldn't be returned to Earth. And it's impossible to set these people straight because they don't listen.

<cue random segue>

Just as the guys running the NASA social gatherings complain all the time about how there's always one idiot asking them if Jupiter could be turned into a star so we can colonize its moons. It's impossible, Jupiter doesn't have enough mass to initiate fusion, the guys at NASA explain this to people repeatedly, the facts are available online, but it simply doesn't sink in to the general public because they SAW Jupiter get turned into a star in the movie "2010".

[Kryten]

Again, you're literally the only person I've ever seen say anything like that except for an actual mission with RTGs. Even stuff like the protests over Cassini/MSL got maybe a dozen people each. You're making a mountain out of a molehill.

I think he means that parachute is used to slow the stages down before hitting the ground.

Which gets you a half-crushed rocket stage without some additional damping force.

Edited November 5, 2015 by Kryten

[fredinno]

Again, you're literally the only person I've ever seen say anything like that except for an actual mission with RTGs. Even stuff like the protests over Cassini/MSL got maybe a dozen people each. You're making a mountain out of a molehill.

Which gets you a half-crushed rocket stage without some additional damping force.

This is what he's talking about: http://www.astronautix.com/lvs/kislerk1.htm\

Parachutes and airbag assisted landing.

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Actually, yes. Which is why SpaceX doesn't use parachutes. The Shuttle SRB parachutes and deployment systems weighed about 4 tons for each SRB. That's nearly 8 tons of wasted payload, and all that for a pretty hard splashdown.

Most first stage engines are started or primed or ignited with ground support equipment. Air starting requires a major redesign of the engine where everything you need to start the engine is integrated into the engine.

I can't find any stats for the amount of fuel used for landing Falcon 9 cores. Do you?