Text in force at CAR3-14: from CAR3-0, effective 1 Nov 1949. OCR text
(a) Oil tanks shall be vented to the engine crankcase from the top of the expansion space in such a manner that the vent connection is not covered by oil under an normal flight conditions. Oil tank vents shall be so arranged that condensed water vapor which might freeze and obstruct the line cannot accumulate at any point.
(b) Category A. Provision shall be made to prevent hazardous loss of oil during acrobatic maneuvers including short periods of inverted flight.