Aircraft appear to be damaged at random with seemingly no rhyme or reason. Attached is a video of this occuring while flying a FS-12 Revoker. Other players in the lobby reported this bug happening with every aircraft in the game. Most notable, it seems to occur in the Compass, Revoker, and Darkreach the most. At best, you'll lose your engines. At worst, your plane suddenly disintegrates.
NOTE: This behavior appears to only occur in multiplayer, as I haven't had it occur yet in singleplayer.