47-10-22 LOCKHEED: (Was Mandatory Note 24 of AD-763-3.) Applies to Model 49 Serials 1975, 1976, 1977, and 2021 Through 2065.
Compliance required prior to March 1, 1947.
Install steel retainer washer (American LaFranch P/N 2CD-3054C) in place of existing aluminum alloy retainer washer on fire extinguisher selector valve.
(LAC Service Bulletin 49/SB-27 covers this same subject.)