core:doevent("open terminal").
wait 3.
local shipheight to alt:radar + vdot(core:part:position, up:vector).

local lptgt to latlng(latitude, longitude).

local tth to lptgt:terrainheight.
lock steering to lookdirup(up:vector, facing:upvector).
lock throttle to 1.
stage.

lock steering to lookdirup(up:vector + north:vector * 0.01, facing:upvector).

wait until apoapsis > 3000 + tth.
lock throttle to 0.
wait until verticalspeed < -40.

local hnow to alt:radar + vdot(core:part:position, up:vector) - shipheight.
set drawVel to vecdraw(v(0,0,0), v(0,0,0), blue, "Landing target", 1.0, true).
until hnow < 0.3 {
  set hnow to altitude - tth + vdot(core:part:position, up:vector) - shipheight.
  local vs to velocity:surface.
  local vv to verticalspeed.
  local tpos to lptgt:position.
  set drawVel:vecupdater to { return tpos. }.
  local bp to body:position.
  local avmag to vv * vv * 0.5 / hnow.
  local avthrmag to avmag + body:mu / bp:sqrmagnitude.
  local tti to abs(vv) / avmag.
  local ah to vxcl(bp, (12 * tpos / tti - 6 * vs)) / tti.
  if ah:mag / avthrmag > 0.1 set ah to 0.1 * ah:normalized * avthrmag.
  local steervec to up:vector * avthrmag + ah.
  lock steering to lookdirup(steervec, facing:upvector).
  local hovslthrot to mass * sqrt(ah:sqrmagnitude + avthrmag^2) / availablethrust.
  if throttle > 0 or hovslthrot > 0.95 {
    set throttle to hovslthrot.
  }
  wait 0.
}

lock throttle to 0.
wait until ship:status = "landed".
set ship:control:pilotmainthrottle to 0.
unlock all.