60-20-04 LOCKHEED: Amdt. 203 Part 507 Federal Register September 28, 1960. Applies to 188 Aircraft Serial Numbers 1002, 1004 Through 1102, 1104 Through 1126, and 2001 Through 2015.
Compliance required by the next 300 hours' time in service after October 28, 1960.
Leaking lavatory tank ground drain valves have permitted drainage to the exterior surface of the aircraft in flight, resulting in ice formation which came off and struck the stabilizer. Since such ice formation is hazardous to aircraft in flight and to persons on the ground, all lavatory tank ground drain valves must be modified to incorporate LAC seal No. 838228-1 or equivalent. (LAC 88/SB-407 covers the intent of this change.)
This directive effective October 28, 1960.