trailing vortex drag

20 LETTERS · STARTS WITH T

trailing vortex drag is a valid 20-letter word worth 31 points in Scrabble and 36 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

T1R1A1I1L1I1N1G2V4O1R1T1E1X8D2R1A1G2

1 + 1 + 1 + 1 + 1 + 1 + 1 + 2 + 0 + 4 + 1 + 1 + 1 + 1 + 8 + 0 + 2 + 1 + 1 + 2 =31 PTS

DOUBLE WORD → 62TRIPLE WORD → 93

MEANING

What does trailing vortex drag mean?