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How Planes Are Maintained

2 min read

The short answer

Airliners are checked before every flight and maintained to strict, legally required schedules — from overnight checks every few weeks to a near-complete rebuild every few years. If a plane isn't fit to fly, it doesn't fly. No exceptions.

The Most Carefully Maintained Machines

Airliners follow some of the strictest maintenance rules of any vehicle. Every check is recorded, every important part has a set lifespan, and no plane flies with an unresolved safety issue.

Four Levels of Checks

  • A-check — every 400–600 flying hours (roughly every few weeks). Routine checks of systems, fluids, tyres and safety equipment, usually done overnight.
  • B-check — every 6–8 months. A more detailed check, taking 1–3 days.
  • C-check — every 18–24 months. The plane is out of service for 1–4 weeks while almost every system is examined in detail.
  • D-check — every 6–10 years. The plane is taken apart, and every part is inspected, tested, repaired or replaced. It's essentially rebuilt over 2–3 months.

Before Every Flight

Before the first flight of the day, a licensed engineer inspects the plane and signs to confirm it's fit to fly. The pilots then walk around the outside themselves, checking the engines, tyres, wings and lights.

Strict Oversight

Airlines must follow maintenance programmes approved by the FAA in the US or EASA in Europe. These authorities make unannounced inspections of maintenance work and records. If a plane isn't fit to fly, it doesn't fly. There are no exceptions.

Parts Are Replaced on Time

Every critical part has a set life limit: a number of flights or hours. After that, it must be replaced, however good it looks. This is a legal requirement, not a choice.

A Complete History

Every plane has a detailed logbook. It records every check, repair and part change throughout the plane's life. Regulators review it, and so do airlines buying or leasing the plane.

Age Isn't the Issue

A well-maintained older plane is safer than a poorly maintained new one. How a plane is looked after matters far more than its age, and every plane must meet the same standards.

Sources

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