Lycoming Engines released Service Instruction 1009BF, extending the operating-hour time between overhaul (TBO) to 2,600 hours for a range of factory-new and factory-rebuilt piston engines.
The update covers selected engines in the O-320, IO-320, O-360, IO-360, IO-390, O-540 and IO-540 families when they are operated and maintained in accordance with applicable Lycoming technical publications and FAA airworthiness requirements.
For qualifying fixed-wing engines, the revised interval can add 400 hours to the previous base TBO, while eligible rotorcraft engines can receive an additional 300 hours. Lycoming said the extended interval was supported by endurance testing and fleet data and was intended to reduce overhaul frequency and improve aircraft availability.
Service Instruction 1009BF also includes updated cautions, parts guidance and instructions for engines affected by AD 2012-19-01. The FAA approved the instruction as an alternative method of compliance for specified provisions of that airworthiness directive.
Eligibility depends on the exact engine model and its build or overhaul status. The current 12-year calendar TBO remains in effect, and operators must apply whichever limit is reached first. Lycoming directs owners and maintainers to the current service instruction and an authorised distributor to confirm eligibility.
