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Headings and degrees


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21 minutes ago, Venus_Andromeda said:

My question is, how can I find out what my degrees are when I'm looking at the navball

Depends what you mean by "what my degrees are".  If you just want to know "which direction is the nose of my ship pointed", you can get that off the navball, it's well-marked.

yDLLtPC.png

...in the above picture, the inclination markers (see the red arrows) tell you how many degrees above or below the horizontal you are, and the azimuth markers (see the green arrows) tell you which compass direction you're heading (0 = north, 90 = east, 180 = south, 270 = west).

However, based on your next comment,

24 minutes ago, Venus_Andromeda said:

i have a craft on the launch pad and I want to do a rendezvous with a craft that's sitting at 400 km with an inc if 29°

...I'm guessing that "which direction is my ship pointed?" isn't actually what you want to know.  I'm guessing that what you really want to know is, "how can I set up a rendezvous?", yes?

If that's the case, then the answer is "it depends"-- specifically, it depends on your ship's current situation (are you on the surface? in orbit? which orbit?  etc.)  So it's hard to give advice without having more specific information about exactly what your situation is and what you're trying to accomplish.

Can you describe in more detail just what it is that you're trying to do?  For example, "I have a ship in <description of orbit> and I want to rendezvous with a ship in <some other orbit>".  It would also help if you could post a screenshot of the map view, showing the ships in question and their orbits.

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Thanks for the fast response

So i have a craft on the pad with an inc of 28.6º.

And another in orbit at 400.5 km x 409.7 km with an inc of 28.2º.

my problem is that if i launch  now when my orbit in complete my inc will be the opposite. i can launch later and line up for the rendezvous but it will be at night and i'd rather launch during the day. so I'm trying to figure out what my HDG should be to achieve the 28.xxº inc when I'm done my burn so i can start my approach. this will be my first of many to come rendezvous 

https://www.dropbox.com/s/1yuj0fdstoreeii/screenshot2.png?dl=0

https://www.dropbox.com/s/kgl95ip6e92jp6y/screenshot3.png?dl=0

i do understand (0 = north, 90 = east, 180 = south, 270 = west). just not sure where to point when i launch so I'm heading in the right direction.

 

thank you very much for the help

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1 hour ago, Venus_Andromeda said:

So i have a craft on the pad with an inc of 28.6º.

And another in orbit at 400.5 km x 409.7 km with an inc of 28.2º.

my problem is that if i launch  now when my orbit in complete my inc will be the opposite. i can launch later and line up for the rendezvous but it will be at night and i'd rather launch during the day. so I'm trying to figure out what my HDG should be to achieve the 28.xxº inc when I'm done my burn so i can start my approach. this will be my first of many to come rendezvous

Gotcha, that helps.

So, if you are launching from KSC, and you want to launch to intercept a craft that has an inclined orbit, you need to launch when Kerbin is rotated such that your ship is under the orbital track of the target (i.e. when you're under the AN/DN of the target's orbit, with respect to Kerbin's equator).

There are two places on Kerbin that will be appropriate for this, located 180 degrees apart from each other (one at the AN, one at the DN).  So, if you like launching during the day, one of those two spots will be in daylight, just pick that one.  You'll either launch slightly north of east or slightly south of east, depending on whether you're launching at the AN or the DN.

Your direction will (roughly) need to match the inclination of the target orbit.  So, if it's at the AN, you'd launch at close to 28 degrees north of east, or roughly 28 degrees south of east if you're at the DN.

I say "roughly" because Kerbin is rotating, and you already have some eastward velocity (a shade over 170 m/s) just due to that.  So your actual surface-relative launch path will be inclined slightly more than the target's inclination, but not all that much-- a couple of degrees or so.

 

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14 hours ago, Venus_Andromeda said:

just not sure where to point when i launch so I'm heading in the right direction.

Just to expand on @Snark's excellent answer, the specific term you're looking for is the launch azimuth. See this thread, and in particular OhioBob's responses, for more in-depth explanation and formulas for how to exactly calculate what launch heading you need. 

 

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