Orbit over a specific point on land?

[Oddible]

Having a lot of trouble getting into orbit over a specific point on land without burning up all my fuel and electrical resources trying to get there. I'm using the 2,868.75Km orbit for geosynchronous but I can't line it up with KSC. I don't have any problems getting a nice circular geosynchronous orbit, my problem is lining it up over KSC. Any recommendations appreciated.

I first launch, then get a stable lower orbit, then prograde burn up to my gso, but I have no idea of where my vehicle will be after the burn, is there some way to get a better sense of my destination location (of course the Pe burn to get my orbit circular blows me way off course). Any adjustments to get over KSC result in changes to my Ap/Pe and after countless adjustments I'm out of fuel or electricity (usually both).

Edited July 19, 2013 by Oddible

[stupid_chris]

How would you be out of electricity?? If you use a probe, you'll have to stick solar panels or an RTG to it, else you'll lose control over it no matter what.

[Starwaster]

raise your apoapsis to GSO when you as close to opposite of KSC as you can. then wait until you are at Ap to finalize your orbit.

it's easier if you use mechjeb because it will detect low TWR and mostly start your burn early if it has to. Mostly.

If you do it by hand then take TWR into consideration when starting your burn. node placement stays the same.

and yes, for godssake put solar panels and batts or rtg...

[Alistone]

You're nearly there.

The "trick" is to just place yourself in a nice circular orbit at 2.5 million m and you will be orbiting with a shorter period than kerbin. This means you will slowly progress until you are almost above KSC. When you get close, increase your apoapsis to the magic number; when you get to your higher orbit apoapsis circularize and you should be nearly perfectly above KSC.

EDIT: And if you don't have an electric generator on board you need to add one to your vessel. Not a battery; an actual generator. (Alternately you could probably get by with battery & solar panels).

Edited July 20, 2013 by Alistone

[arq]

If you launch straight from KSC out to a 2868km apo, then raise your peri so that you have a 4-hour orbital period (use Engineer, Mechjeb, or double the time difference between your apo/peri), and wait 1 or 2 orbits like that, you will get an apo very close over KSC. Scott Manley has a recent YouTube video about geosync that does that.

Otherwise, from geosync, if you drop your orbit slightly you will move faster relative to the surface and you you raise it you will move slower. The issue is that you want to be at 2868km when KSC goes under you.

Remember, the most important part for staying over a place on the ground is to have exactly a 6-hour orbital period. Really, without a ton of extra work, most of my geosync orbits vary by maybe 5km, but I use engineer to get 0.1s/orbit synchronization so they don't drift.

[Oddible]

Thanks all, I use Engineer (I don't want the hand holding of MechJeb just yet, plus I find all the MechJeb parts ugly and huge, and they consume electricity).

I have 4 batteries currently, and I DO have solar panels but you can't burn with solar panels out right?

An electric generator consumes fuel.

[Kimberly]

Thanks all, I use Engineer (I don't want the hand holding of MechJeb just yet, plus I find all the MechJeb parts ugly and huge, and they consume electricity).

I have 4 batteries currently, and I DO have solar panels but you can't burn with solar panels out right?

An electric generator consumes fuel.

You can burn with solar panels just fine. If you do this in the atmosphere, then there will be drag on the solar panels as you move through the air and the force causes them to break. But in vacuum, there's no drag, so it makes no difference whether your solar panels are extended or not.

[NGTOne]

Thanks all, I use Engineer (I don't want the hand holding of MechJeb just yet, plus I find all the MechJeb parts ugly and huge, and they consume electricity).

I have 4 batteries currently, and I DO have solar panels but you can't burn with solar panels out right?

An electric generator consumes fuel.

You can burn with panels out, you just can't fly through atmo with them.

And the RTG (stock generator) only produces a trickle of power, but doesn't consume fuel.

[astropapi1]

Just set your Ap at keosync, coast until you reach it, and burn prograde until your Pe is ~15 km below keosync. Timewarp until you're roughly over KSC, and the circularize at AP.

IIRC, you want your orbital period to be 6 hours, as that's what a Kerbin day lasts.

Hope it helped.

[Starwaster]

You're nearly there.

The "trick" is to just place yourself in a nice circular orbit at 2.5 million km and you will be orbiting with a shorter period than kerbin. This means you will slowly progress until you are almost above KSC. When you get close, increase your apoapsis to the magic number; when you get to your higher orbit apoapsis circularize and you should be nearly perfectly above KSC.

EDIT: And if you don't have an electric generator on board you need to add one to your vessel. Not a battery; an actual generator. (Alternately you could probably get by with battery & solar panels).

reread that.... two point five MILLION KILOMETERS???

Thanks all, I use Engineer (I don't want the hand holding of MechJeb just yet, plus I find all the MechJeb parts ugly and huge, and they consume electricity).

I have 4 batteries currently, and I DO have solar panels but you can't burn with solar panels out right?

An electric generator consumes fuel.

sounds like you're buying into the hype. some people around here would have you believe that if you use mechjeb you're cheating. that it's a magic one button solution to everything. want to go to the Mun today? just click here and it will launch, plan your orbit and transfer and do an orbital insertion not to mention planning your Kerbal's itinerary when they land. The truth is that you will be the one doing the hand holding. you will watch over it's shoulder every step of the way. you will ask for an orbital solution and then cancel it and ask again. or after a few times of that you will plot it yourself because Eve is coming up awful fast and you only want to visit, not die here.

you will tell it to give you a munar flyby with a periapsis of 20 miles only to have it try to plow right through the Mun.

You will assume manual control because the rudder on your rocket is waving frantically to and fro like mechjeb is trying to wave down a taxi and you need that rudder hard to starboard because you REALLY want to go to space today.

dont get me wrong, I love mechjeb and I DO let it fly my ship alot but it needs watching and a human to take over frequently because it doesnt always do the right thing. It's a tool and I've learned a lot watching how orbital mechanics work because of mechjeb. I'm probably a better pilot now than I was before.

Edited July 20, 2013 by Starwaster

[lammatt]

true, mechjeb is only good at lifting the vessel into kerbin orbit