53-11-02 de HAVILLAND: Applies to Model DHC-2 (Beaver) Aircraft, Serial Numbers 1 to 445 Inclusive.
Compliance required as indicated.
Cases have been reported of chafing of the engine oil sump by section assemblies. (P/N C2-E-105ND) and (P/N C2-E-107ND) of accessory firewall. An enlarged flange clearance is required to be incorporated as soon as possible but not later than the next 100 hours.
The FAA concurs in this mandatory action by the Canadian Department of Transport.
(de Havilland Technical News Sheet, Series B, No. 64 dated March 23, 1953, available from de Havilland Aircraft of Canada, Ltd., Toronto, Ontario, Canada, covers this same subject and describes method of repair.)