Commonwealth Numbered Regulations

1988 NO. 158 CIVIL AVIATION REGULATIONS - REG 258

258. An aircraft shall not fly over water at a distance from land greater than
the distance from which the aircraft could reach land if the engine, or, in
the case of a multi-engined aircraft, the critical engine (being the engine
the non-operation of which when the other engines are in operation gives the
highest minimum speed at which the aircraft can be controlled) were
inoperative, except:

   (a)  with the prior approval of the Authority; or

   (b)  in the course of departing from or landing at an aerodrome in
        accordance with a normal navigational procedure for departing from or
        landing at that aerodrome.