Service Bulletin No. 643
Crankcase Nut Safety Wire Inspection
September 16, 2021
Lycoming engines identified in Tables 1 and 2
TIME OF COMPLIANCE
Aerobatic engines – within the next 10 hours of operation or next scheduled maintenance event, whichever occurs first (Table 1).
Non-aerobatic engines - within the next 50 hours of operation or next scheduled maintenance event, whichever occurs first (Table 2)
Product Support Network
Wherever you are in the world, you have access to exceptional expertise and knowledge about Lycoming engines. Get the most comprehensive customer service and support in the general aviation industry.
Get It Exchanged
Use our Engine Exchange Program to order a new, rebuilt, or overhauled engine to experience more airtime and less downtime.