X0101 EFFECT 33 LIVE 2017-07-21 0001193125-17-230299 POS AM 0000073887 Bristow Group Inc 333-206535 0001707378 Bristow Academy, Inc. 333-206535-06 0001707377 Bristow U.S. Leasing LLC 333-206535-05 0001058606 BRISTOW U.S. LLC 333-206535-04 0001557799 BHNA Holdings Inc. 333-206535-03 0001419682 BRISTOW HELICOPTERS INC 333-206535-02 0001058607 BRISTOW ALASKA INC 333-206535-01