Aerobraking...

[IllicitMedic]

Been playing KSP since May...I've built a space station, been to Mun and Mimmus but have never done an interplanetary flight yet.

I see everyone talking about Aerobraking to save delta v while transferring to other planets moons...what exactly is it and how is it executed? I'm assuming it involves skimming the atmosphere?

Edited July 17, 2013 by IllicitMedic

[AlteranEmpire]

Aerobraking is skimming the atmosphere to slow down where you would normally spend a lot of fuel to slow instead.

"Aerobraking is a spaceflight maneuver that reduces the high point of an elliptical orbit (apoapsis) by flying the vehicle through the atmosphere at the low point of the orbit (periapsis). The resulting drag slows the spacecraft. Aerobraking is used when a spacecraft requires a low orbit after arriving at a body with an atmosphere, and it requires less fuel than does the direct use of a rocket engine."

[regex]

Dipping into a planet's atmosphere in order to shed excess velocity. The periapsis for aerobraking is different for each planet, but it needs to be within the planet's atmosphere.

http://wiki.kerbalspaceprogram.com/wiki/Aerobraking

[rryy]

Normally when you encounter a planet, you are traveling much faster, so it will take quite a lot of delta-v, but with aerobraking, you can save a lot of delta-v by using the atmosphere to slow you down. It involves having your periapsis low enough so that it enters the atmosphere and slowing down during recently to lower your apoapsis. However, having your periapsis too high, you will still be on a hyperbolic trajectory after aerobraking, but too low, you will soon be lithobraking.

[MockKnizzle]

Yup. You can use atmospheric friction to bleed off your excess speed. Aerobraking is particularly useful for slowing down after an interplanetary transfer out to Eve, Duna or Jool, since it allows you to get captured for free. It's also occasionally used during Kerbin returns, if you want to slow down gradually without smashing directly into the atmosphere at 10G or more.

[IllicitMedic]

Awesome guys thanks! (Don't know why I didn't check the wiki)

Thanks again.

[Flixxbeatz]

IRL, it's aerobraking. In KSP, it's aeroBREAKing

[scolton]

There's a really excellent and (relatively, in rocket science terms) simple aerobraking forumula that I've been using with good success to plan aerobraking adventures in KSP: http://www.planetaryprobe.org/sessionfiles/Session6B/Presentations/5_Forget_Aerobraking_Equation.ppt. I turned it into a spreadsheet which has served me very well, especially trying to squeeze every last ounce of fuel out for visiting Jool/Laythe.

(I know there are other tools for planning KSP aerobraking but I found it exciting that a formula developed for real-life missions can apply fairly accurately to the game using only parameters you can get from the parts list and map screen!)

Some Jool aerobraking fun:

http://i.imgur.com/LEIFQTE.jpg

[Cashen]

There's also this aerobreaking calculator online that I find useful. http://alterbaron.github.io/ksp_aerocalc/

[MalfunctionM1Ke]

But be carefull. Digging to deep into the atmosphere of a planet might be fatal.

It is like the fangs of a black widdow. She is lurking you with desire but feasts on your flesh while you are hugging on her skin.

[Kimberly]

But be carefull. Digging to deep into the atmosphere of a planet might be fatal.

It is like the fangs of a black widdow. She is lurking you with desire but feasts on your flesh while you are hugging on her skin.

In what world do black widows "lure you with desire"? Spiders creep me the heck out.