Abstract: A crane apparatus is provided with a lock mechanism which releasably locks the pivot axle of the personnel bucket against pivotal movement relative to the upper boom arm. The pivot axle is affixed to the bucket and projects through and is journaled on the upper boom arm. Locking elements are affixed to the pivot axle and clamping elements are affixed to and mounted within the upper boom arm. A locking bolt is operable to cause the clamping elements to be clamped against the locking elements and to lock the pivot axle against pivotal movement relative to the upper boom arm.