Aircraft maintenance is an area of significant importance because maintaining an aircraft in a good condition increases aviation safety. Modern aviation maintenance is divided into four checks: A; B; C; and D checks. These checks are carried out at predetermined times based on the number of flight cycles (landings and take-offs) or flight time. These checks are performed under a maintenance program founded on MSG-3.
History of MSG-3
In 1968 the Boeing Company developed the Maintenance Steering Group (MSG), maintenance schedule to ensure the safety of their B747-100 aircraft . This approach moved away from the tradition of "overhaul and replace at time intervals" to one that considered the type of tasks and intervals needed to keep the aircraft safe. MSG was found to be very successful because it saved time, money and unnecessary interference with components therefore, the company found a need to apply the same approach to all their aircraft. Thus, MSG was made applicable to more aircraft by making it more general. This new general version was named as MSG-2. However, over time MSG-2 was found to have some significant drawbacks (Kinnison, 2004 1). To overcome these failures MSG-3 came into existance in 1980. Today, most of the world's aircraft maintenance organisations are using MSG-3 approach.
Drawbacks of MGS-2
- Does not take the economic view into the considerations. Simply maintains aircraft safety at any cost
- Does not treat hidden failures to pilots: electric and electronic failures, fatigue inside the structure etc
- Is a bottom-up approach requiring more staff
- The definitions in MSG-2 contradicts themselves
- Does not take the modern corrosion prevention approach into account
Advantages of MSG-3
- Top-down process
- Reduced maintenance costs
- Fewer maintenance tasks
- Some tasks are carried out for economic reasons and others for safety reasons
- Eliminates emotions
Aircraft Maintenance Checks
A Check is a light check carried out usually overnight at an airport gate. This check is carried out every month or every 500 flight hours, however, depending on the aircraft type the timing can change.
B Check is also a light check carried overnight at an airport gate. This check is normally performed every 3 months.
C Check is a heavy maintanance check usually carried out every year or every 1.5 years. Since this check requires dessembly of critical parts, this check is performed in a hangar.
D Check is sometimes called overhaul check or heavy maintenanc check. This check is performed in every 4-5 years: inspection of entire aircraft is carried out.
Knowledge Management Space
- More information about D Check