Plan landing site "perfectly" effectively without burning more fuel than necessary

[paul23]

Well I'm really wondering how you guys plan a landing?

Landing at the equator or near the poles is simple enough: you just break at the right time and plan ahead.

However landing at (say) 45 degrees longitude seems to me very hard. You can create a polar orbit and wait till your orbit is over the position. However then more often than not the satellite is on the opposite of the Mun. And once you're back you'll be off by 20-30km, far from ideal.

And then the hovering/landing in itself: even on an equatorial landing spot I can't seem to get "closer" than 2-5 km.

[ForScience6686]

I find it best to land a small probe that can be targeted. Then with the nav ball in surface mode, adjust prograde marker to slightly below target. That will indicate you're ship will over shoot the target. Adjust as you get closer. I can routinely bring it down within 100m. Atmospheric landings are much harder if you don't have a plane.

[paul23]

I find it best to land a small probe that can be targeted. Then with the nav ball in surface mode, adjust prograde marker to slightly below target. That will indicate you're ship will over shoot the target. Adjust as you get closer. I can routinely bring it down within 100m. Atmospheric landings are much harder if you don't have a plane.

Well the problem is: I don't have a probe at the "take temperature as site xyz".

[Alshain]

Well I'm really wondering how you guys plan a landing?

Landing at the equator or near the poles is simple enough: you just break at the right time and plan ahead.

However landing at (say) 45 degrees longitude seems to me very hard. You can create a polar orbit and wait till your orbit is over the position. However then more often than not the satellite is on the opposite of the Mun. And once you're back you'll be off by 20-30km, far from ideal.

And then the hovering/landing in itself: even on an equatorial landing spot I can't seem to get "closer" than 2-5 km.

The Mun is tidally locked. It takes over 6 days to rotate once, it won't move that much in a single orbit and what little it does move you can adjust with a radial burn.

[paul23]

Well I was trying to "plan ahead" so that my landing site would be in sunlight (initial approach I discovered it was in the shadow for 2+ more days). But when I landed and did the temperature measurement it didn't give me any indication I succeeded (I did manage to get a success to a part where I only needed to fly over a certain spot). Apparently I'm off a bit - but I see no indication of how far or how I should've done it.

[Retread]

I have a mining operation on Minmus at about 35° latitude, and use a tanker/rover to transfer fuel between it and an orbiting refuelling station. Here's a summary of my landing procedure. Note that the tanker starts in a 20km circular equatorial orbit.

1. On the opposite side of Minmus from the landing site, burn retrograde until the periapsis is about 3500m. This altitude varies on different bodies, I try to get as low as possible without creating a chance to impact a mountain range. Your periapsis should now be above the equator, directly south or north of the landing site.

2. Create a maneuver node halfway between apo- and periapsis, and plan for a normal or anti-normal burn that will bring your orbit directly over the landing site. Add sufficient retrograde to maintain the periapsis at the same height as before. Complete this burn, and your periapsis should now be directly over the landing site, although there's no need to be too exact.

3. Create a maneuver node about 10° before the landing site, and plan for a retrograde burn that leaves you intersecting the ground beyond the landing site. This will be your initial landing burn.

4. Create a second maneuver node between the landing site and inital landing burn, and plan for enough retrograde so that your orbit intersects the landing site.

5. As you get close to the initial landing burn, you may need to adjust where the burns are due to Minmus' rotation. The idea is to make the final burn so that the lander is coming down near vertically close to the landing site.

6. Execute both burns. You should now be close enough to the landing site to steer the lander in manually the rest of the way.

[Alshain]

Well I was trying to "plan ahead" so that my landing site would be in sunlight (initial approach I discovered it was in the shadow for 2+ more days). But when I landed and did the temperature measurement it didn't give me any indication I succeeded (I did manage to get a success to a part where I only needed to fly over a certain spot). Apparently I'm off a bit - but I see no indication of how far or how I should've done it.

It should flash a warning on the screen when you enter the zone, but it is very short lived. If you use the Waypoint manager mod, you get a persistent indicator in the form of flashing distance/countdown to target timer.

[ForScience6686]

Well you can activate navigation on those spots. No probe needed, that was more for when I set up mining where I had to continuously land in the same spot.

[FancyMouse]

I haven't landed from orbit to high latitude area, but how about the trick of burning to push retrograde towards target?

[paul23]

Well you can activate navigation on those spots. No probe needed, that was more for when I set up mining where I had to continuously land in the same spot.

I activated it and it didn't do anything, what should I see in my navball?

@fancymouse: problem is: I only see the "targets" when in orbit view, not when viewing the actual spacecraft. And even zooming in I can't seem to see it close enough for the objective.

[FancyMouse]

Oh I misunderstood. If it's a target waypoint not a ship, then the best way is unfortunately a design change - put a retro probe core on your ship, control from it while landing. This lets you see the waypoint on navball during landing.

[paul23]

retroprobe core?

[mdkendall]

retroprobe core?

FancyMouse means a probe core facing the other way, i.e. pointing downwards when you land.

When you click on the waypoint marker in the map view and choose to enable navigation, you get a marker on your navball showing the direction to the waypoint. The problem is, your ship is likely pointing upwards when you land, so you see the "sky" (blue) half of the navball, and the target is in the "ground" (brown) half, so you can't see it. One trick is to keep tilting the ship over as you come down to get a peek at the target marker. This requires you to know roughly where it is. Alternatively, if you have a probe core (e.g. the OKTO) mounted say underneath your crew cabin, facing downwards (i.e. flip it when you mount it), then before landing you can right-click on it and "control from here". The navball will flip over, showing you the brown half and the waypoint marker.

[DancesWithSquirrels]

I use the Trajectories mod - it takes into account rotation of the body you're orbiting, air resistance (make sure to specify whether you're coming in prograde or retrograde for an atmospheric body, as your aerodynamics matter quite a lot), and shows you a marker where you're going to land. I can usually get within 1km of my target with very little effort that way.

Set your initial landing point just past your target, then do a retro-burn 1-2km above it and do fine adjustments on the final descent.

The Navball should show you your target and target relative trajectory - on final keep your retrograde velocity vector on or just around your retrograde target vector, monitor your vertical speed, and there you go.

Edit: Scott Manley has a great video on landing on target:

Edited October 28, 2015 by DancesWithSquirrels

[jiminator]

The planet navigation is probably the weakest part of KSP. You can help with either NavHud and/or Waypoint Manager. NavHud will put all of your navball markers on the hud, they also move as your ship moves so it is easier to track destinations. Waypoint Manager will put a big marker on your hud, it also shows distance and ETA in addition to being able to do other things. Both IMO are essential to doing navigation on planets.

As for those types of contracts... you can just decline them with no penalties. IMO they are just too hard and annoying to do with very little payoff. On Kerbin, fine, you get to build cool planes. On moons/planets though you are mostly talking rockets and each landing is going to be expensive.

It is good to learn how to do precise landings, but probably better to use them for building a base or rescues or so on. Changing inclinations and landing for temperature readings... just not fun.

All that being said... there is an anomaly surveyor that gives contracts to visit the various easter eggs in the game. VERY worthwhile, and it will test your landing skills in some places.