Dumb question.... probably....

[jl0179]

I was just wondering why NASA or other shuttle launching companies don't launch from places that are higher up in the atmosphere to begin with? It seems logical for NASA to have a launch site in say Denver during at least the summer months in order to gain that extra altitude and save fuel since fuel is the single heaviest thing that the shuttle or any rocket for that matter ever has to carry. I realize weather would play a role in the winter months but it seems like for at least 3 months out of the year they could get some better results if they had a second site there.

 

[mikejz]

A few issues <br /><br />1) While Alt is a factor, so is the latitude of the launch site--as relatively speaking the earth turns fasts the closer you are to the equator. I'm not sure of a very southern CONUS area that is also high in elevation.<br /><br />2) Range: There is a reason why KSC launches out over the Atlantic and Vandyland over the Pacific---so the boosters do not travel over populated areas. I'm not sure there is a tract of gov't land that is large enough to provide for an orbital launch. <br />

 

[jl0179]

Ok well lets speak hypothetically then and say that we are launching from the top of a mountian site in mexico or north africa or india, is there any reason other then proximity to the equator, population density, and bad weather that would stop a company from launching off the side of a mountain? Some physical reason why this isn't feasable? Would the lower amount of oxygen hurt the initial launch or anything like that?

 

[edkyle98]

If the launch was from Denver, the first stage would fall in the general vicinity of Kansas City! Not a good thing!<br /><br />At least one U.S. launch vehicle (Pegasus) does gain an altitude advantage by being drop-launched from an aircraft at 40,000 feet. This method of launch is said to reduced delta-v requirements by 10-15%, thanks to a reduction in drag and gravity losses. By extrapolation, a launch from only 5,280 feet might only make a 1-2% difference. <br /><br /> - Ed Kyle

 

[drwayne]

There have been a number of - vigorous discussions over the years about mountain launch/rail launch/plane launch/balloon launch - some of which post date the big crash - a search might well provide some interesting reading.<br /><br /><img src="/images/icons/smile.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[tap_sa]

<font color="yellow">"Some physical reason why this isn't feasable? Would the lower amount of oxygen hurt the initial launch or anything like that?"</font><br /><br />space rockets, shuttle included, carry their own oxygen inside the tanks, so that is not the issue.<br /><br />Major why shuttle won't be launching from mexico, africa or india is that countries prefer to launch rockets from pads on their own soil. Space access is considered strategically very important and so it is natural to keep related assetts firmly on domestic soil and juristiction.<br /><br />Other reason is that possible mountain launch sites are usually on very remote areas. Launch site like KSC is a BIG infrastructure, building it is an immense task and requires oodles of resources. Building something that big to a hard to get places is prohibitely expensive.

 

[jl0179]

I did a search of mountain launches and turned up almost no results, on here as well as on google.<br />Also it seems that even a 2% diffrence in fuel would be helpful when your talking about 1000's of tons of fuel. Obviously it's not enough for NASA to just pick up and start all over again but perhaps a new space operation by a private company should look at possible high altitude sites in mexico to base it's operations. It just seems to me that if your goal is to get from A to B it's kind of dumb to start at Z unless there is a logical reason for it that can't be gained from another, just as remote, but much higher in altitude site.

 

[jschaef5]

Having the range safety factor out ways the benefits from the altitude by far...<br /><br />There is a spaceport being built in New Mexico however, but I doubt that altitude had any factor in the decision to put it out there. <div class="Discussion_UserSignature"> </div>

 

[josh_simonson]

They won't be cleared to drop empty tanks from the tourist 'spaceports' either. RLVs can launch anywhere.

 

[barrykirk]

There are some very tall mountains in Hawaii.<br /><br />That has three advantages.<br /><br />1) US Soil<br />2) High Altitude<br />3) Closer to the Equator than KSC.<br /><br />Of course it would overfly the coast which I believe is densly populated.

 

[drwayne]

"There HAVE been other flights that overflew some level of population. A series from Utah into the White Sands range comes to mind, and there must be others."<br /><br />When I was working a test program, target launches came from Fort Wingate down to WSMR, and things had to be done to make sure we didn't drop debris into the White Sands National Monument.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[frasercain]

A.... very... dumb.... question.... indeed!

 

[tap_sa]

<font color="yellow">"Of course it would overfly the coast which I believe is densly populated."</font><br /><br />But not US west coast. Depending on inclination and always aiming for the 'descending' part of orbit (it has some fancy term can cannot remember right now) the vehicle shoots directly to east or south-east from Hawaii. It flies over central or south america (and nobody cares about that... <img src="/images/icons/wink.gif" /> )

 

[teije]

The most famous 'land' launch site in the world is of course Baikonur. I think it is elevated quite a bit above sea level as well (although I can't seem to find the actual altidude at the moment.) The disadvantages are noted above. The main advantage is usually (but not necessarily) easier recovery. For example, the soyuz launch escape system (and normal landing for that matter) is designed to launch on land. This is 1 of the reasons why ESA that is building a soyuz launch facility in Kourou cannot use it (yet) for manned launches. Kourou launches over sea!<br /><br />1 of the most poetically beautiful things about cape canaveral I always find is in Jules Verne's 'From the earth to the moon in 28 days and 12 hours' written in 1865! He pinpoints his moon gun at 27 deg 7 min North, 82 deg 9 min West. Only a little more than 100 miles from the Cape. <br />Jules Verne had a huge imagination and was no fool.

 

[tomnackid]

"The most famous 'land' launch site in the world is of course Baikonur."<br />-------------------------------------------------------------------------------------------<br /><br />I understand that peasants living down range from Baikonur could make extra income by salvaging spent boosters and selling them for scrap--those that didn't succumb to poisoning from hypergolic fuel residue! Those wacky marxist countries and their concern for their citizens and the environment. <img src="/images/icons/wink.gif" />

 

[teije]

Yep, it is a scarcely populated area, but there ARE people living there. And it is NOT healthy. <br /><br />I guess the reasoning in the 50's was indeed that they just didn't care all that much. Today... well... the people may not like it that toxic rocket exhaust descends on their home every now and then, but Baikonur is a major source of income to Kazakhstan, so I don't think the (Kazakh) government will do too much about it.

 

[nacnud]

The Souyz can land on water if needed, ie an emergency. So far only Soyuz 23 has had to, but that landed on a frozen lake so I'm not sure if it counts.

 

[vogon13]

<img src="/images/icons/laugh.gif" /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[teije]

Really? I never knew... <br />O well, I was wrong about that then. <img src="/images/icons/smile.gif" /><br />Can it also land on water when the launch escape system is triggered? <br />It would have to be pre-programmed for water landing, or it would have to somehow detect that it was landing on water.

 

[vogon13]

The Soviet era 'shuttle killer' splashed down on (IIRC) 2 test flights.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[henryhallam]

<font color="yellow">Also it seems that even a 2% diffrence in fuel would be helpful when your talking about 1000's of tons of fuel.</font><br /><br />It's worth nothing that for any multi-stage launch vehicle, reducing first stage mass by x tonnes only increases the payload capacity by some smallish fraction of x. This would probably be offset by the reduced initial velocity caused by the more northern latitude.