Its not like vtols have random movement... you decide to cruise or flank, you decide when and where you will turn, you decide if you will continue moving after a turn, and you know before you make the PSR exactly where you will end up if you fail. If a vtol can crash is entirely determined by the controlling player.
Not entirely true. While the movement is not 100% random, unintentional Sideslipping IS random because it is based on dice roll's Margin of Failure. There is some control over it by choosing not to Flank, keeping the movement to the potential Sideslip minimal, and/or having a well-skilled pilot, but it actually happening and the distance can be random in most games.
While VTOLs have more control over this than Hovercraft, I've Slipped Hovercraft in to terrain too many times because of the nature of the terrain. I either have to stop early (thus minimizing TMM) or have to turn late to avoid making another turn or more to get to my desired location. VTOLs can at least alter their Elevation to avoid problematical terrain before committing to the turn, but sometimes one forgets, or one Slips just that one hex too far and greets Woods the next hex over. It also usually means being at an elevation where one can be seen, and therefore shot. In a world of Pulse Lasers and Flak, that can be just as dangerous.
So while control exists, the randomness also exists.
I have no idea what this has to do with AM engines, though, other than providing an interesting random way of accidentally clearing terrain.
