CRAYMER’S COUNSEL
Robert Craymer - robertc@covingtonaircraft.com
Hot Section Inspections Maintenance time is just ahead for many operators. Shops are starting to fill out schedules for off-season work. One of the maintenance items that is frequently discussed is the need for an engine hot section inspection. While hot section inspection time requirements may differ by engine model, the “mid TBO” recommendation usually applies. Performance loss can also dictate the need for an inspection. For example, the PT6A-34AG engine TBO (Time Between Overhauls) is 4000 hours, and hot sections are recommended at 2000 hours. For the PT6A65AG, the basic engine TBO is 3000 hours, and the recommended hot section inspection is 1500 hours. All this information exists for all engine models in various Pratt & Whitney Canada service AF 16 | aerialfiremag.com
bulletins. Time constraints are listed in service bulletins, but each engine model’s maintenance manual defines the hot section inspection criteria. What exactly is a hot section inspection? The hot section inspection is the way of making sure the condition of some of the hardest working parts in your engine can continue to do the job up to the next inspection interval or until TBO. The PT6 engine is all about efficiency, and the hot section inspection is a simple and fast way to confirm the engine is not losing efficiency in this extreme environment. Because of the temperature and forces applied to the parts in the hot section, a wide variety of factors can change efficiency just through normal operation. Fretting, wear,
