From dec15th there is ONE 'direct' train to and from BRU (Brussels Airport) .
departure 06.29 in BRUGES, arriving in BRU-airport 08.04 .
from BRU-airport towards BRUGES(destination OSTEND):
departure 16.06 at BRU-airport, arriving in BRUGES 17.37.
the word 'direct' means here: you don't have to change trains. and these 'P' trains (P stands for PEAKHOUR) stop in several stations.
of course there are a lot more trains to the bru-airport from bruges, roughly every half an hour, but you have to change trains then.