Define "marginal deviation"...before I destroy my sattelite out of spite!

[strider3]

GRrrrr! I have a contract to place a new satellite in an equatorial orbit around Kerbin. All requirements of the contract are met (green check marks) except "reach the designated equatorial orbit around Kerbin within marginal deviation".

Here's how close I am:

AP: required - 3,826,804,  actual - 3,826,861

PE: required - 3,109,860,  actual - 3,109,764

Inclination - required 180/-180,  actual - 180 / -180

Argument of Pe - required 83.2*, actual - ???

All things are matched up in the orbit map with the required orbit. I don't know what "A of Pe" is, but I've been told that if everything else is matched, it does not matter?

How close do I have to be?

Vic the Newbal

[smjjames]

Do you have a screenshot of what you're trying to do?

Generally you need to have the AP and PE in the locations of the desired orbit marker.

And Argument of PE is a real PITA to do sometimes.

[reapersms]

Argument of Pe describes the orientation of the ellipse around the central body.

If your Inclination numbers are what it shows for the AN/DN indicators, it sounds like you have a perfect orbit... going the wrong direction. 180 degrees of inclination means head west from the launchpad, not east. You'll need a bit more dV, as you have to counteract the eastward boost Kerbin gives you. I think on the order of ~10% or so.

[strider3]

After digging around more deeply here, and installing KER's AoP abilities, my AoP is 284*. I do believe you are right, Reaper...I'm going the wrong way! LOL. Just to verify "0* of inclination" would mean head east? Don't think I have enough fuel to reverse rotation, going to start over...and change the LV-909 Terrier, on the probe, to a Twitch...more forgiving for fine orbital adjustments.

[Nich]

400 dv to be safe as ground speed is 175 m/s on the pad

[reapersms]

I've certainly made that mistake a few times, usually summed up with some colorful language when I get there. 0* of inclination would indeed be east, in a bog-standard equatorial orbit.

If you don't need to really get it moving, a twitch should work. Alternatively, you can adjust the thrust limiter once in flight for a lot finer control. For exceedingly fine-tuned stuff, I'll knock it down to 10-25%. Set right, you can use mammoths to adjust orbits.

[KocLobster]

26 minutes ago, reapersms said:

Argument of Pe describes the orientation of the ellipse around the central body.

If your Inclination numbers are what it shows for the AN/DN indicators, it sounds like you have a perfect orbit... going the wrong direction. 180 degrees of inclination means head west from the launchpad, not east. You'll need a bit more dV, as you have to counteract the eastward boost Kerbin gives you. I think on the order of ~10% or so.

+1 to this. Incredibly likely you've got a perfect orbit going the wrong way. I've found those particular contracts to be quite lenient. I always get surprised when it completes and I still feel like I have a bit more perfecting to do.

18 minutes ago, Victor3 said:

After digging around more deeply here, and installing KER's AoP abilities, my AoP is 284*. I do believe you are right, Reaper...I'm going the wrong way! LOL. Just to verify "0* of inclination" would mean head east? Don't think I have enough fuel to reverse rotation, going to start over...and change the LV-909 Terrier, on the probe, to a Twitch...more forgiving for fine orbital adjustments.

Are you aware you can lower engine thrust in flight? Right click and there is a slider thingie for thrust limiter. You can slide this down to decrease your engine's thrust.

Sorry if I assumed incorrectly, it just sounded like you may not be aware of this.

[strider3]

To clarify, yep, know about thrust adjustments (but thanks!). And not a Twitch (I misspoke)...I replaced the Terrier with the Spark. It's more than enough to get my orbit right.

I completed that contract, so...thanks gang! I'm onto another, around the Mun. And I hope to have enough fuel left after contract to go into a polar orbit. I have a survey scanner on this one and hope to locate some ore.

Thanks again, all!

Vic the Newbal.

[BoggyDG]

What you can also do is, if you have multiple satellite contracts, and use a rocket that is totally overpowered(on mine i don't even separate the mk2 engine off my rocket bcs i have like 3000 dv left), you can place all the necessary equipment on a single rocket, go to one of the trajectories, and then after finishing the contract reposition it to the place of the other contract. I did that once when i had all of the equipment and thought it would be cool not to send a second rocket but use that one instead. I did a gravity assist with Mun so i get the orbit with less delta v.

[mrclucks]

This isn't related to your OP but since it was answered, this relates to your other question/comment. 

After 2nd level radar, can and launch pad, I'll usually upgrade the facility that gives contracts(unsure what the name is right now) so I can accept as many satellite contracts as they will give me.  Then I build a rocket with as much DV as I can pack on and go complete them all as efficiently as I can.  I find it's the best way to get alot of munies for a small investment.  

[KocLobster]

3 hours ago, mrclucks said:

This isn't related to your OP but since it was answered, this relates to your other question/comment. 

After 2nd level radar, can and launch pad, I'll usually upgrade the facility that gives contracts(unsure what the name is right now) so I can accept as many satellite contracts as they will give me.  Then I build a rocket with as much DV as I can pack on and go complete them all as efficiently as I can.  I find it's the best way to get alot of munies for a small investment.  

Administration building.

[Chakat Firepaw]

11 hours ago, KocLobster said:

Administration building.

Mission Control actually, Admin is where you either pick strategies or simply never go.

[ColKlonk]

Argument of Pe, is the angle from the Ascending node (the point where the ship rises above the equatorial plane - Earth/Kerbin or any round object in space ) to the Periapsis point.

https://en.wikipedia.org/wiki/Argument_of_periapsis

It helps identify the rotation angle of the orbit. Apoapsis will be on the opposite side

 

Edited April 21, 2016 by ColKlonk

[KocLobster]

8 hours ago, Chakat Firepaw said:

Mission Control actually, Admin is where you either pick strategies or simply never go.

Yeah that one haha 

[Wemb]

On 19/04/2016 at 0:24 AM, Victor3 said:

After digging around more deeply here, and installing KER's AoP abilities, my AoP is 284*. I do believe you are right, Reaper...I'm going the wrong way! LOL. Just to verify "0* of inclination" would mean head east? Don't think I have enough fuel to reverse rotation, going to start over...and change the LV-909 Terrier, on the probe, to a Twitch...more forgiving for fine orbital adjustments.

I think we've -all- done that at some point.  At least, in this case, it was a satelite.  You don't want to be in the position I got myself in when I returned an Asteroid - into the correct, apart from being backward, orbit the contract requested.  That was not a profitable year for the KSP.

But, yeah, you can thrust limit the engines as others have said for fine control - though in most cases, once you've achieved orbit, a Terrier is probably huge overkill for a satellite. A spark would be better than a twitch though - you'd need two twiches for a start, they're not much lighter and their are a lot less efficient.

Wemb

[strider3]

6 hours ago, Wemb said:

I think we've -all- done that at some point.  At least, in this case, it was a satelite.  You don't want to be in the position I got myself in when I returned an Asteroid - into the correct, apart from being backward, orbit the contract requested.  That was not a profitable year for the KSP.

But, yeah, you can thrust limit the engines as others have said for fine control - though in most cases, once you've achieved orbit, a Terrier is probably huge overkill for a satellite. A spark would be better than a twitch though - you'd need two twiches for a start, they're not much lighter and their are a lot less efficient.

Wemb

Yep, meant Spark not Twitch ;-)