Airplanes play a significant role in making flying the safest medium of travel. Operators expect their aircraft to fly safely with minimal or no incidents caused by mechanical failure. With hundreds of moving parts and highly-complex mechanisms, airplanes require routine inspection and maintenance.

The aircraft structure goes through extreme stresses during a routine flight from point A to point B. While the cabin is pressurized and depressurized for the breathability of passengers, the outer body is exposed to extreme temperatures.

Similarly, landing gears absorb large forces upon touchdown while brakes and tires take a significant beating. The same goes for hundreds of other parts and systems.

Preventive maintenance philosophy

In the early days of commercial aviation, the aircraft maintenance philosophy was based on timed inspections and maintenance. With a preventive maintenance strategy, almost all critical and non-critical systems came with a time limit for maintenance.

For example, an Auxiliary Power Unit (APU) would go through dismantling and maintenance at regular intervals. During a maintenance check, functional parts would be replaced with new parts, and the limit is zeroed until the next interval is reached.

In 1960, the Federal Aviation Administration (FAA) and several airlines from around the world established a task force to measure the effectiveness of the preventive…