Text in force at 23-63: from 23-43, effective 10 May 1993.
A drain [or drains] must be provided to allow safe drainage of the oil system. Each drain must--
[(a) Be accessible;
(b) Have drain valves, or other closures, employing manual or automatic shut-off means for positive locking in the closed position; and
(c) Be located or protected to prevent inadvertent operation.]
58 FR 18973 · Source