52-11-02 CONVAIR: Applies to All Model 240 Aircraft.
Compliance required not later than the first major engine overhaul after February 1, 1953.
To improve further the engine nacelle fire resistance of 240 aircraft, steel facings must be installed over certain aluminum alloy components of the engine cowl panels, the oil cooler duct, and the nacelle structure forward of the firewall.
(Convair Service Bulletin No. 240-425, Revision 2, describes these changes in detail. Preliminary information on this modification is contained in Convairogram No. 30, dated April 8, 1952.)