Hi all - my first Post here - sorry for my non-perfect english

Has anyone some tips on deorbiting and Landing at a base?
And what is that ship "jumping" on the atomsphere approach, and how can i control it? (I once have seen A
Star trek chapter where a young Officer was flying in a shuttle, who wasnt able to escape the g´s from a
Planet - Jean-Luc radioed him to approach atmosphere at straight 90 degrees so that he would bump off the
atmosphere (of course the french Captain was right

) - is this something like that ?
Thanks for your help in advance
P.S. : a (working) website with a Landing manual is okay too