47-20-08: Battery box drain

47-20-08 ERCO: (Was Mandatory Note 16 of AD-718-6.) Applies to 415-C, -CD and -D Aircraft. Compliance required prior to July 1, 1947. (a) Install a new battery box drain tube to extend at least 1/2 inch below the fuselage belly skin if this has not been already incorporated in the airplane. (b) Examine the fuselage structure and controls carefully for corrosion. If corrosion is found on the structure, the affected areas should be washed with an alkaline solution and followed by a thorough clear water rinse. Corroded controls should be replaced. (c) Examine the baggage compartment for deterioration. If damage is evident, wash the affected area with a diluted alkaline solution and rinse with clear water. Reinforce any damaged areas with 10 1/2-ounce single filled water-resistant canvas, double sewn with 16-4 glace finished thread. (d) Install decalcomania (Erco P/N 415-54062) on the top of the battery box cover. (Ercoupe Service Department Memorandum No. 44 dated February 17, 1947, and Ercoupe Service Department Bulletins No. 8 dated May 24, 1946, and No. 22, dated February 3, 1947, also cover the above subjects.)