Rocket base too high removes cone

If the landing pad is build to near the top, the rocket lands, but the cone is not accessible anymore. If you remove one part, the cone comes down though, so its still there, but you cant use it, and therefore you cant set a new destination anymore. Only "solution" rebuild the rocket on lower space. 

Suggestion: Check if the rocket will fit the pad, and refuse to move there, if the rocket would be too large.