Taking off from other planets/moons, how to orient yourself?

[Magzimum]

When I take off from anywhere other than the launchpad, my orbits are far from parallel to the equator. I am looking for tips and tricks to improve my skills on this.

I guess it could help if I orbit the planet/moon on an equatorial orbit, but often the orbit is not along the equator. Especially with the other planets, it is often too much dV to get on an equatorial orbit. I guess it could help if I align my ship before landing, using the navball, but I am usually too busy with "not crashing". I guess it could help if I landed on a flat surface, but often I am on a hill, which means that my gravity turn starts in whatever direction I am tilted. 

On Minmus, with its low gravity, I sometimes use a tiny bit of dV to turn my ship before take-off, but on other bodies I don't because it is a risky maneuver.

I am looking for tips to take-off in the right direction, thereby making the procedure more efficient...

This is not a ship-related question, so I did not post pictures.

[mhoram]

18 minutes ago, Magzimum said:

I am looking for tips to take-off in the right direction, thereby making the procedure more efficient...

Have a look at your Navball. You can see on the edge between the blue and the orange hemisphere numbers (0, 45, 90, 135, ...). They indicate the direction you are facing with your rocket.

If you want to make your orbit after take-off as equatorial as possible, then point your rocket in the "90" direction. The reason is that the numbers represent the compass points (North = 0/360, East = 90, South = 180, West = 270). (Note: launching in the West direction also makes your orbit equatorial, but I would not recommend this since you have to counter the planetary rotation, which means that you need more fuel to get into orbit)

As you have noticed, the latitude of your landing site has also an impact on the orbit after launch. The farer you land away from the equator, the less your orbit gets equatorial after launch. If the orbit before landing is equatorial, then your landing site will also be near the equator, so this should help to get you into an equatorial orbit after launch.

[Palaceviking]

Also put a thermometer on every pod on the south side, so you are looking at it on the launchpad.

Helps to know which way is forward later.

[Plusck]

Pointing due east on takeoff will always give the least inclination to your orbit, as @mhoram has explained.

I have in the past been tempted to fly towards the equator first, then turn east as speeds increase. My reasoning was that plane changes at low speeds are not expensive, therefore reducing the inclination while still very suborbital would be efficient.
However, that doesn't work at all really - at low speeds you take a long time to cover any distance, so by the time you get closer to the equator you're going so fast that the plane change is very expensive. So as a method it fails utterly.

Instead, I do the whole takeoff and re-orbiting process in Map view only (perhaps looking at the outside view for the first few seconds just to ensure I'm not heading for a mountain) while targeting a vessel in orbit. This is to make sure that the flightpath is indeed due east to start with, and that the AN/DN with the equatorial orbit is exactly at the point that my Ap touches it at the end of the first major burn. Then I circularize with the plane-change at Ap, which is definitely the cheapest place to do so, and am perfectly aligned with the destination orbit.

Of course, the downside is you miss seeing the ground screaming past you on your way to orbit :/

Edited August 30, 2016 by Plusck

[Magzimum]

@mhoram, I know the navball, and use it. However, my landers almost never touch down the right way, so they are pointed in various directions. It is all easy if I just have to press D a bit to turn to the horizon, like from the launchpad. But I often struggle a bit, perhaps also because I watch the main screen a lot, and maybe not enough at the navball. Another reason is that I find it a lot harder if the rocket is already pointed 20 degrees towards (e.g.) the northeast, and I need 2 keys (e.g. D and S?) to get the rocket pointed to the 90 degree marker. I understand the physics, and the mechanics to steer the ship, but it's all just very clumsy and inefficient.

Is any of you able to orient the lander before landing? Or do you all rotate it the right way after take-off, then initiate the gravity turn by pressing the D to go to the 90 degree marker? Or first the gravity turn using whatever WASD keys are needed, and then rotate? Or perhaps even just start the gravity turn, and who cares about rotating the craft?

@Palaceviking, I like the idea of putting a tiny thermometer (does it have any drag?) on the capsule / pod. At least it helps to know which way is which. Going to implement that on my designs. Worst case I may get a little extra science if I accidentally pass through another biome... although the perfectionist in me would protest, and say that I then must put ALL science equipment on it, because it makes no sense to go to a new biome and not max out the science harvest.

Anyway, thanks for the answers already - looking forward to see a few more!

 

Edited August 30, 2016 by Magzimum
adding @[name] to the post

[Palaceviking]

I can see people obstructing hatches with thermometers around the world right now....doh.

[Plusck]

15 minutes ago, Magzimum said:

... But I often struggle a bit, perhaps also because I watch the main screen a lot, and maybe not enough at the navball. Another reason is that I find it a lot harder if the rocket is already pointed 20 degrees towards (e.g.) the northeast, and I need 2 keys (e.g. D and S?) to get the rocket pointed to the 90 degree marker. I understand the physics, and the mechanics to steer the ship, but it's all just very clumsy and inefficient.

Is any of you able to orient the lander before landing? Or do you all rotate it the right way after take-off, then initiate the gravity turn by pressing the D to go to the 90 degree marker? Or first the gravity turn using whatever WASD keys are needed, and then rotate? Or perhaps even just start the gravity turn, and who cares about rotating the craft?

It sounds like you should force yourself to look only at the NavBall. It's difficult to ignore what you see on the screen but (mountains aside) it's much less important than what the NavBall is teling you.

You have plenty of time to orient yourself once you've taken off. It isn't like landing when a misstep will have you crashing to earth, and it isn't like taking off from Kerbin with the atmosphere forcing you to get the right path straight away.

So just take off at full power, then look only at the NavBall and turn gently to face slightly above the horizon line at 90°. If prograde starts dropping too much towards the horizon, point more towards radial-out. It doesn't matter if you take a bit of time to do this - it'll be slightly less efficient but it'll also make sure you're above any hills.

 

And no, I don't orient the lander as such when landing. Rather, on the final approach to landing, I rotate so that the "ground" brown part of the NavBall forms an arc at the top. That means that when following the craft, left and right are the right way around and forwards and back are inverted, which for my brain is easier to manage. It also means that if I land without rotating, it's just W again to head east.

[Red Iron Crown]

1 hour ago, Magzimum said:

Or do you all rotate it the right way after take-off, then initiate the gravity turn by pressing the D to go to the 90 degree marker?

I do it this way. Don't worry if your lander is on a slope and pointed in the "wrong" direction, that is pretty easy to fix in the first few seconds after lift off. My method is: Launch -> point straight up -> roll to preferred orientation -> begin gravity turn. Better pilots probably skip the roll and go straight to the gravity turn, but for someone with modest piloting skills like me this works well enough.

[Aegolius13]

As mentioned above, the best way to get an equitorial orbit after landing is to be in one before you land.  And the best way to do that is to plane change at the AN or DN, or at least well away from the planet/moon while maneuvers are still cheap.  This may seem like overkill for the Mun or Minmus, but it's a vital skill for Moho, the Jool moons, etc.

If you start at an inclined orbitand don't want to plane change, the best thing you can do is to land where your orbit crosses the equator.  But that may be hard based on topography.  You can always wait for the planet to rotate a bit and put better terrain under the equator.

On takeoff, just point navball at 90 degrees and burn as flat as you can while avoiding the terrain (in vacuum, at least).

[OhioBob]

3 hours ago, Red Iron Crown said:

I do it this way. Don't worry if your lander is on a slope and pointed in the "wrong" direction, that is pretty easy to fix in the first few seconds after lift off. My method is: Launch -> point straight up -> roll to preferred orientation -> begin gravity turn. Better pilots probably skip the roll and go straight to the gravity turn, but for someone with modest piloting skills like me this works well enough.

^this^

Plus I always roll to the correct takeoff attitude while descending.  Just before landing rotate the craft so that it is in the orientation you want it to be for the latter takeoff.

(edit)  Assuming you want to takeoff due east using right yaw (D key), as you're falling rotate the vessel until the orange radial line on the NavBall (indicating North) is pointed straight downward.

 

Edited August 30, 2016 by OhioBob

[pincushionman]

4 hours ago, Palaceviking said:

I can see people obstructing hatches with thermometers around the world right now....doh.

If you have a hatch there you don't need an extra feature. Though the problem isn't usually (lt least for me) aligning the the ship with the camera, it's in aligning the camera with the planet. Knowing how the navball works helps a lot, but having a camera snap-to-direction would be a great boon. The "project navball on the screen" mods help with this, though.

[Magzimum]

Well, the good news is that I did this: All your help (in this thread and a few others) resulted in Jeb having a pretty decent launch from Eve, aligned with the orbital plane of the orbiter (only 2.1 degrees off), and eventually meeting up with the orbiter with some fuel left in the tanks. First time that I landed at Eve, and actually made it back to orbit!!  

I did the method of pointing straight up (which was an issue, since I was on a hill), and looking only at the navball. On Eve you want to go straight up for quite a while so after I had managed to get the prograde marker also pointing straight up, I had time to rotate my ship. Then I initiated the gravity turn - or something that could perhaps go for one, because I started turning it pretty late because of some design flaws (ship wanted to flip in thick atmosphere). Regardless of the tiny issues I still had, I am delighted, and so is Jeb. Your feedback helped. Thanks all! 

I'll probably post some pics of the whole endeavour at a later stage - too tired now  

p.s. I asked about the equatorial orbit to keep the discussion/tips a little easier to follow. My actual problem was to meet up with the orbiter which was not equatorial at all - but the problem is the same, just the navball marker is a different one. I mostly wanted to know what steps you all take, and in which order, so I could work on my own take-off strategy, to replace the current "press Z and panic" method... 

 

Edited August 30, 2016 by Magzimum

[Plusck]

2 hours ago, Magzimum said:

Well, the good news is that I did this: All your help (in this thread and a few others) resulted in Jeb having a pretty decent launch from Eve, aligned with the orbital plane of the orbiter (only 2.1 degrees off), and eventually meeting up with the orbiter with some fuel left in the tanks. First time that I landed at Eve, and actually made it back to orbit!!  

I did the method of pointing straight up (which was an issue, since I was on a hill), and looking only at the navball. On Eve you want to go straight up for quite a while so after I had managed to get the prograde marker also pointing straight up, I had time to rotate my ship. Then I initiated the gravity turn - or something that could perhaps go for one, because I started turning it pretty late because of some design flaws (ship wanted to flip in thick atmosphere). Regardless of the tiny issues I still had, I am delighted, and so is Jeb. Your feedback helped. Thanks all!

 

Wait, what... this was Eve you were talking about.

Eve is hard. Really hard. You get gazillions of brownie points for it.

I'm sorry, I wouldn't have said anything like "you have plenty of time to orient yourself" if I had thought for a second you were talking about Eve, ffs!

Did I miss something in the OP?

Eve.

[Magzimum]

5 hours ago, Plusck said:

Did I miss something in the OP?

Nah, but if I had said Eve, then people would go on about all kinds of other issues than the problem I had (at least that's what I expected)...

[edit] Actually, until quite recently I would also waste a lot of fuel launching from other bodies, because I was disoriented and did not have a clear plan how to get the rocket/lander into a proper orbit. My previous "strategy" was to just hit Z, and correct the course until it was in some orbit. So, this was not only about Eve. I just decided to test the lessons learned on Eve first.

Edited August 31, 2016 by Magzimum

[Laie]

Actually, RIC's advise is double worthwhile on Eve. Even with the much reduced atmosphere, you still have to go straight up for quite some time before you can even think about doing a turn. Plenty of opportunity to adjust your roll as you like it.

On a low-g place like Gilly, you just take off in whatever direction you're pointed, kill engines, turn sideways, and boost. Again, plenty of time.

The tricky ones are places like the Mun or Duna where you want to initiate a turn quickly.

[Magzimum]

I agree with @Laie that the Mun and Duna are places where quick turns are needed. With some practice and determination, you can probably still go straight up first, then rotate, and then do the gravity turn.

On Gilly, the story is quite different. If Jeb farts, the whole mothership will hover for 30 seconds.

[Sonny_Jim]

20 hours ago, Aegolius13 said:

As mentioned above, the best way to get an equitorial orbit after landing is to be in one before you land.

Correct me if I'm wrong, but every single orbit possible will cross over the equator at some point, so unless I am going for a specific biome, I land on the equator, makes taking off again that bit easier.

 

Also, on any body without an atmosphere you want to start going sideways as soon as possible, not just Duna/Mun.

Edited August 31, 2016 by Sonny_Jim

[Aegolius13]

2 hours ago, Sonny_Jim said:

Correct me if I'm wrong, but every single orbit possible will cross over the equator at some point, so unless I am going for a specific biome, I land on the equator, makes taking off again that bit easier.

Correct.  But the closer your starting orbit is to equitorial, the closer your landing site will be if you don't get it exactly right.And if you're equitorial beforehand, you can pick and choose for the best terrain, needed biome, etc.

 

3 hours ago, Sonny_Jim said:

Also, on any body without an atmosphere you want to start going sideways as soon as possible, not just Duna/Mun.

Also true, though sometimes you have to go steeper to avoid mountains in your way and so forth.  Duna does have an atmosphere but it's very thin, do you may want to go a bit steeper than in a vacuum.

[Sonny_Jim]

18 minutes ago, Aegolius13 said:

Duna does have an atmosphere but it's very thin, do you may want to go a bit steeper than in a vacuum.

Ah of course, it's so thin I forget it's there sometimes lol.  

I seem to remember reading somewhere that the effects of atmospheric drag are minuscule compared to the losses of going straight up to orbital height then gaining horizontal speed takeaway I took from this was, it doesn't matter that much how early you start your gravity turn on Duna/Laythe/Kerbin (Eve I wouldn't be so sure of).

Edited August 31, 2016 by Sonny_Jim
Err orbital speed, not height

[Red Iron Crown]

Just now, Sonny_Jim said:

I seem to remember reading somewhere that the effects of atmospheric drag are minuscule compared to the losses of going straight up to orbital height then gaining horizontal height.  The takeaway I took from this was, it doesn't matter that much how early you start your gravity turn on Duna/Laythe/Kerbin (Eve I wouldn't be so sure of).

Generally speaking gravity losses are greater than drag losses, so yes it's better to make an early, fairly aggressive gravity turn. The limit on Kerbin and Eve tends to be thermal, ideally the rocket goes as fast as it can as low as it can without burning up. Duna can effectively be treated like a vacuum world; its cold, very thin atmosphere and reduced orbital speed means it's pretty unlikely you'll burn up.