Life-limited parts (LLPs) in PT6 and JT15D engines enforce mandatory replacement at specific cycles/hours to ensure safety and reliability. Proper tracking prevents surprise AOGs and overhauls for King Air, Cheyenne, and Citation operators. What Are LLPs? LLPs include critical turbine disks, shafts, and hubs certified to finite lives (e.g., 5,000-10,000 cycles). Unlike on-condition parts, they