60-04-03 LOCKHEED: Amdt. 100 Part 507 Federal Register February 9, 1960. Applies to All Model L-188 Airplanes Equipped With Lord Engine Mounts Number LM-204A-SA4.
Compliance required as indicated.
As a result of two incidents of front Lord engine mount fatigue failures on units of old design the following must be accomplished:
(a) Inspect mounts for cracks particularly in the web and fillet areas upon next arrival at scheduled stop where maintenance facilities are available and repeat this inspection at intervals not to exceed 50 flight hours. Any mounts with cracks must be replaced immediately with LM- 204A-SA5/Lockheed P/N 632182-9.
(b) Replace all LM-204A-SA4 mounts with LM-204A-SA5 mounts within 300 flight hours after first inspection required by (a) but not later than March 1, 1960.
(c) All spare quick engine change units must be modified to include the new SA5 mounts prior to installation in aircraft.
(Lockheed Service Bulletin No. 228 covers thissame subject.)
This airworthiness directive sent by telegram to all operators of 188 aircraft on January 11, 1960.