problem aligning orbits with atlantis space shuttle

[caningo]

Hi everyone

My name is caningo and I am new to orbiter. I must say this game is freaking amazing. I downloaded it last night and have been playing for like 6 hours hahaha. :rofl:

I was playing the flight where you liftoff from KSC and have to release a satelite in orbit. I instead decided to go to the ISS.

I've read all the steps to get there but when I get to part where i have to align orbits I get a really crappy rate of inclination diff. (-0.003 deg/s) which takes forever to reach the ISS orbit. Is that normal? My difference in orbits was like 70 something degrees but i had not even gotten to half of that when i was almost out of fuel.

Can someone plz help?? Can i get that rate of inclination diff. to be a little bigger? or is it maybe my copy of Orbiter has a bug or something? :sorry:

Thanks a lot for all your help. I look forward to good times in the game and in these forums.

caningo

 

[Woo482]

I think you might be burning in the wrong direction If I am correct you need to point 15 degrees above pro grade when you want to change orbits in the space shuttle

 

[Urwumpe]

No, all is fine. The low rate of inclination change comes from some design aspects of the space shuttle:

-Low thrust of the OMS - both OMS engines can only produce 0.6 m/s² acceleration.
-Low amount of total impulse - the OMS of the space shuttle can only change your velocity vector by 1200 feet per second or 365.76 m/s

Next problem is the required amount of impulse for changing your orbit. Plane change maneuvers are painfully expensive.

70° plane change cost dV = 2 * sin(70°/2) * current velocity ~ 8930 m/s in your case. That is almost as much as the total impulse used for putting the space shuttle into Orbit.

Better directly launch into the orbit plane of the ISS and avoid large plane changes. More than 0.5° difference is not recommended, as it leaves you with only little fuel for rendezvous after you subtracted the fuel required for orbit insertion and deorbit (both all together around 180 m/s)

For launching into the right orbit plane, you have to roll the shuttle after launch and aim for a heading of 42° from KSC, as well as launching when the orbit plane will be passing your launch site in about 85 seconds.

 

[Woo482]

wow the OMS's are very slow

 

[Urwumpe]

Slow? They have just low acceleration. The Shuttle travels at over 28000 km/h! Slow is something else.

 

[Woo482]

My car goes faster than that my car goes 28001 km/h!!!!!!!

 

[ar81]

Hi everyone

I've read all the steps to get there but when I get to part where i have to align orbits I get a really crappy rate of inclination diff. (-0.003 deg/s) which takes forever to reach the ISS orbit. Is that normal? My difference in orbits was like 70 something degrees but i had not even gotten to half of that when i was almost out of fuel.

Can someone plz help?? Can i get that rate of inclination diff. to be a little bigger? or is it maybe my copy of Orbiter has a bug or something? :sorry:

Thanks a lot for all your help. I look forward to good times in the game and in these forums.

caningo

This tutorial will help you to visually understand what you are doing when trying to reach ISS

[ame="http://www.orbithangar.com/searchid.php?ID=3074"]Tutorial: DG to ISS[/ame]

 

[caningo]

THANX

Hey guys,

Thanks a lot for everything. I figured my level of proficiency at Orbiter isnt that good to be flying the shuttle to the ISS and especially if the I have settings on limited fuel! :lol:

I decided to fly the DG and got close to the ISS but then gave up cuz my orbit got screwed up and I ended up reentering Earth... :dry:

I'll def. try the shuttle when i get better at it.

caningo

 

[Vipers]

Hi

why in the Align-plane MFD the Inclination of the ISS is 59.83° and in the Launch MFD is 51.61°?

is a problem of the mfd or am I that mistake?

I post an image

 

[Urwumpe]

Align plane MFD measures ecliptic inclination, launch MFD equatorial inclination. Both measure the same orbit plane in different reference frames.

 

[Arrowstar]

Hey guys,

Thanks a lot for everything. I figured my level of proficiency at Orbiter isnt that good to be flying the shuttle to the ISS and especially if the I have settings on limited fuel! :lol:

I decided to fly the DG and got close to the ISS but then gave up cuz my orbit got screwed up and I ended up reentering Earth... :dry:

I'll def. try the shuttle when i get better at it.

caningo

You actually need limited fuel with the shuttle or you'll never make it to orbit!

 

[SlyCoopersButt]

Not if some fuel is removed first by scenario editor.

 

[Master of Blades]

Hey Caningo, have you read "Go Play in Space"? It Provides a good tutorial on how to get to the ISS

 

[caningo]

Hey Caningo, have you read "Go Play in Space"? It Provides a good tutorial on how to get to the ISS

Hey Master of Blades,

Yes. I tried go play in space and to tell you the truth is was an amazing reference. I learned a lot from it.

One thing i wasn't doing right was waiting for the orbits to align themselves as much as they could over KSC and then do the correction burn. Most of the times i had an Rinc of like 30 degrees or some ridiculous amount. Just think how much fuel wasted!

Things you learn with practice I guess...

Thanks for the recommendation!