launching vessels from a mountain base

[xendelaar]

I performed a small non scientific test just for giggles which i would like to share.

Summary

I transported a simple launch vehicle to the highest mountains near the KSC and performed a launch from there. The idea was to save delta V getting into orbit, since the atmosphere is thinner at higher altitudes.

I performed one test from the launch pad and one test from the mountains at an altitude of 5500 m. it was pretty difficult to land on the mountains and it took quite some effort to get the launching site good to go.the test from the mountains was approximately 100-200 delta v cheaper than launching from the Launchpad. I only performed one test and I have to admit that my ascent profiles were not optimal in both cases… So it would be inappropriate to draw any scientific conclusions out of this one test, but fudge it… :

Launching from the mountains will save some delta v but isn’t worth the effort.

Long story,

I was commuting from work the other day when I came up with a brilliant idea: Why not build a launch platform on the highest mountain ridge on Kerbin?! The high altitude and thin atmosphere would potentially save tons of mass and delta v. The thinner atmosphere would also make the high efficiency engines more attractive as a first stage. I knew this probably has been tested many times in the past, but I didn’t care. I just wanted to do the test and deliberately didn’t perform any search queries on the interwebs to avoid spoilers.

When I got home I did a small altitude scan of the surface of the planet and performed some math. The highest mountain on Kerbinis approximately 6000 m high… According to my excel-sheet, that would mean that I theoretically could save a “whopping†200 delta v getting into orbit. Needless to say, I was a bit disappointed. But still, I wanted to test if it could be done.

So I built a small launching vehicle with 0,25t payload with approximately 3900 delta V budget and created a TurbJet tug to transport the vehicle to the nearest mountains. I landed on a plot at an altitude of 5500m, decoupled the tug and launched my vessel into an 80 km orbit. My ascend profile wasn’t very efficient and when I reached orbit I had 200 delta V left in the tanks. I didn’t feel like redoing the test because I knew it wasn’t worth the hassle. Next, I launched the same vessel but this time I launched it from the ksc launch pad. The ascend profile in this case was also a bit inefficient. I started my gravity turn a tad too late. I ended up in an 80km orbit with 10-20 delta v left in the tanks.

So in “conclusion†I would say, launching from a mountain is viable option to reduce fuel requirements to get something into orbit. However, the gains do not outweigh the extra effort which is needed to transport your vessel

I will upload some pictures from the mission later on.

Edited October 16, 2015 by Vanamonde

[Azimech]

Probably one of the reasons Kennedy Space Center is at sea level, instead of high in the mountains: logistics. The others being safety for the public (crashes in sea) and the fact it's nearer to the equator.

So on Kerbin it's a waste of effort. Building a permanent base and launchpad on the highest point on Eve, that's a different story.

[MalfunctionM1Ke]

ONCE UPON A TIME!

There was an Eve with a different heightmap (Terrain) It also had a very large plateau-ish area and people used to land there and lift off again and it saved ALOT of deltaV.

[mikegarrison]

ONCE UPON A TIME!

There was an Eve with a different heightmap (Terrain) It also had a very large plateau-ish area and people used to land there and lift off again and it saved ALOT of deltaV.

Reminds me of Larry Niven's "Known Space" which had a planet named Plateau with only one habitable area -- the flat area on the top of Mount Lookitthat (so-named by the flight crew of the first ship exploring the planet).

[Grumman]

Reminds me of Larry Niven's "Known Space" which had a planet named Plateau with only one habitable area -- the flat area on the top of Mount Lookitthat (so-named by the flight crew of the first ship exploring the planet).

Better that than Mount Ohgodthatsnotacloud.