What is your minimum orbit altitude?

[Superfluous J]

Usually between 75 and 80, sometimes as low as 72 or so, sometimes as high as 90. The biggest deciding factor really is how quickly I hit X (or how many times I mistakenly hit Z) when setting my apoapsis.

I don't worry about time warping too much. I just set a KAC alarm for whatever I want to do with the ship and then go do something else.

[PB666]

Docking is 100 to 110, since the next transfer orbit can be 75 to 100 and I can phase and serially tighten at 100apo to intersect. If you run at 70 or 75 there is no space below to accurately use to close an orbit and you will have to burn prograde well over 100 to create an apogee for phasing.

I don't find any value of trying to use anything below 75, you loose to much in drag during the gravity turn, my first apo target is 55k at which point Im turning pitch down to small theta, around 70 cutting thrust and estimating how much time I need to finish a circularizing burn and keeping my eye on the Time to apogee.

Something I remember v = h(2/r - 1/a)^0.5 h = SQRT(GM) = 1879255 <---velocity if orbit was one meter

In this case 1 r = 700000 and a = 700000 therefore v = h/836.35 = 2246.97 m/s (this seems a little low)

In the case of the transfer its 2a = 700000 + 1000000 = 2 * 850000. v = h * .00071007 = 2436.28 m/s

The transfer begins with dV of 189.3

The desired orbit is h/1000 = 1879.255 m/s elliptical apogee speed however is 1705.4 or dV = 173.86

Two acceleration events are needed.

There is a fellow by the name of Kepler he and Newton conspired to take the earth out of the center of the universe. Its all wikified now so . . . . .

[monstah]

80 gives me just enough space below to rendezvous efficiently, so it's my pick.

[Alshain]

My minimum is 70k, but I much prefer the view from 300k.

[Wabbit]

I learned my lesson about bare-minimum orbits when the Jelly Lab In Space station re-entered. There were only escape pods for 2, so Seanlocke, Joeger, Billy-Bobfred and *sniff* Bill all burned up or exploded. Seanvan and Herfen escaped in DERP pods.

So now I have an <80 standard. My new station is in a 100k.

[Freshmeat]

Usually go for 80km, but the point about accuracy in burns at a higher orbit did not escape. You learn something new every day.

[Hannu]

If I am going to Mun or Minmus, my typical orbit is 125 km because warp factor. For interplanetary burns I prefer 300 km orbit. It takes little larger launcher, but there are no tools for accurate long prograde burn.

[Slam_Jones]

In most cases, 70km. If it's a station in permanent LKO, I'll either put it at 75km (for ease of rendezvous) or 165km (for framerate).

[OhioBob]

I aim for ~75 km unless it is something that I plan to dock with. If I plan to dock with the ship then I aim for ~90 km, which allows me to launch the second ship into a ~75 km orbit and play catch up.

[Overfloater]

My minimum orbit is at the minimum orbit (69km), but usually I go for 73~75km just in case

[Renegrade]

For Kerbin SOI missions: 72km (2km buffer as I don't like it if wobble puts me under 70).

For interplanetary missions: 100km (TWP tool and page default to 100km orbit, I got tired of typing in correction. Plus it reduces the chance of a longer burn dipping into the atmosphere)

For stations that I might use on a regular basis: 120km (low to reduce fuel wastage of going to a higher orbit)

For long term stations or satellites that won't be visited often but have to be in "low space" for various reasons: 240km

My last Jool trip put the station in between Pol and Bop. Although it's probably less efficient (I have yet to do a study of that), I do find high parking orbits to be more.. relaxing.

[Robotengineer]

Usually a parking orbit at 80km, and stations at 100km to 120km+. If it's something I have to dock with later, 100 or greater. Bad rhyme.

[regex]

I generally park at about 300km ~ 400km, gives me time to make a transfer burn, but really, you have to get above 130km to clear the atmosphere, so that would be the minimum.

[Bill Phil]

Usually 70 k for most missions, but my standard fleet orbit is ~600 km.

[RogueMason]

180km at minimum for missions that are taking immediate effect. 240km plus for stations and things awaiting transfers.

[SorryDave]

For setting up an interplanetary/moon transfer, the lower the better (71K) to save fuel. I also start lower when setting up to dock with a higher (100K-200K) target.

When entering orbit of an airless target, I also aim as low as possible to get the most from my fuel. Of course I do this so the target is slowing me down, not "assisting" me out of the SOI.

[cantab]

My *minimum* is 70 km. My target might be higher, but that's the bare minimum periapsis I consider stable.

[ddenis]

I aim to Ap 100 km and Pe from 80 to 100 km. It's needed because my second stage often has TWR ~0.5-1 at ignition, so I need time for circulation.

[Bioman222]

My standard orbit is 85 km, unless my fuel budget is low, in which case 70 km is fine.

[ajburges]

My stations sit at least 120 Km for 100x time warp. All orbital ops drop all but 180 m/s dv before reentry at the stations (maybe I'll find a use for that) so I aim for that orbit during operations. (allowances for special cases requiring a tug to break 75 Km). Initial orbit is 80 Km unless the launch is close to intercept.

I may make a high efficiency tanker to support higher stations for interplanetary work (one or two timescales higher).

I keep a Kerbstationary probe for beautiful time warps (high radial symmetry).

[ScottWright]

This is a silly question isn't it? It depends entirely on your rocket's TWR and the destination.

First of all, the most efficient parking orbit, is to not have one at all. Just burn straight into the transfer from the launchpad.

But of course, it is much easier to use a parking orbit. The next best thing is to transfer from a low altitude of 69,078 meters.

Then again, you can't have a TWR of infinity, and it is more efficient to burn along the maneuver node instead of the prograde. You'll have to set a parking orbit altitude higher based on the time it will take you to do the maneuver to prevent your rocket from going into the atmosphere again.

You can improve your TWR efficiency and prevent dropping into the atmosphere by doing several orbits on the transfer burn too.

[match]

125 km standard parking orbit for me. Used it for initial orbit while inserting satellite relays with Remote Tech (3 birds @ 776 km) and found it useful as a rallying point for most other operations.

[Leszek]

My first few orbits are normally 85x85. Which is what I selected on the poll. After that, when I get the gravioli detector I start at 85x85 as well. Some of this is because one of my first orbits are collecting EVA reports from orbit and the lower faster orbit makes it easier to cover all biomes in two orbits.

After that my normal parking orbits are 110x110. My space stations are normally at 200 and 300 fro station science mod reasons. My boost to put the Komstilation geosync sat network up starts at a parking orbit of 300 to get an almost exactly 1/4 turn boost to geosync orbits.

[Excalibur.]

I aim for the x10 warp altitude.

[xrayfishx]

I use RSS so my parking orbit is 130 minimum and usually it's around 180 and can go up to 400. It depends on the launch profile of the launch vehicle and the purpose of the satellite being launched. For example, if the second stage of the launch vehicle has low TWR, then I'll throw the Ap to over 400 to be able to circularize. By the time it's circularized the Ap has fallen to below 400 and I'll circularize there with a second burn. However, if it has a high TWR, I will be able to circularize low where it's easier to deorbit the last stage. Also, with high-TWR stages getting to a higher orbit takes more time which can make it harder to circularize.

I never go below 150, because irl a satellite there would complete one orbit at best.