51.—(1) Every ship shall have sufficient power for going astern to secure proper control of the ship in all normal circumstances. The ability of the machinery to reverse the direction of thrust of the propeller in sufficient time, and so to bring the ship to rest from maximum ahead service speed shall be demonstrated and recorded.
(2) The effectiveness of any supplementary means of stopping or manoeuvring the ship shall be demonstrated and recorded.
(3) Every ship with multiple propellers shall undergo trials to determine the ability of the ship to manoeuvre with one propeller inoperative.