In considering whether to approve a proposal, the Secretary must, in respect of the effect that the controlled activity, if carried out, will have on the efficiency or regularity of existing or future air transport operations into or out of the airport concerned, have regard to:
(a) the opinion of the proponent of the activity; and
(b) the opinion of the airport - operator company (if any) for the airport; and
(c) any opinion of CASA; and
(d) any opinion of Airservices Australia; and
(e) if the airport concerned is a joint - user airport--any opinion of the Department of Defence; and
(f) any opinion of the building authority concerned; and
(g) any other matters the Secretary considers relevant.