47-10-26 LOCKHEED: (Was Mandatory Note 29 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075.
Compliance required prior to June 1, 1947.
Reroute flap and fan motor drain lines to return direct to main hydraulic system instead of through aspirator, and install check valves at points where drain lines connect to the main system.
(LAC Service Bulletin 49/SB-169 covers this same subject.)