What is Half-life and Full-life?

Aircraft maintenance status terminology 

Half-life

Sometimes also known as half-time – is a standard industry appraisal term to indicate that no value adjustment has been made for the actual maintenance status of the aircraft. It thus enables a comparison to be made between values of aircraft of different types and ages using a common denominator. It does not indicate that the aircraft is half-way through its useful life.

The term “half-life” refers to the airframe, engines, (propellers, blades, gearboxes where relevant) landing gear, APU and all major components being halfway between major overhauls, inspections or performance restorations as appropriate; with engine life limited parts (LLPs) having 50% of their certified lives remaining.

The values for new or nearly new aircraft are given assuming a “half-life or better” status, which is explained later.

Full-Life

The term “full-life” assumes that the airframe, engines, (propellers, blades, gearboxes where relevant) landing gear, APU and all major components are either new or have just undergone a major overhaul, inspection or performance restoration as appropriate; with engine LLPs having 100% of their certified lives remaining.

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