TYPES OF AIRCRAFT MAINTENANCE
Aircraft maintenance is divided into two sections called 'Scheduled Maintenance' and 'Unscheduled Maintenance'. Standard scheduled maintenance is further divided into three types of checks called: A Checks C Checks D Checks The A Check Usually carried out every eight to 10 weeks, filters will be changed, key systems (like hydraulics in the ‘control surfaces’ that steer the aircraft) will be lubricated and a detailed inspection of all the emergency equipment (like inflatable slides) is completed. A typical A Check on B737 takes between six and 24 hours. The C Check Happens every 18 months to two years or 1,800 flight hours, or 2,000 cycles (depending on type of aircraft) and takes three weeks. C checks can be further subdivided into C1, C2, C3, and C4 where the level of maintenance increases. During C Check, in-depth systems checks, inspection for corrosion, cracks, structural defects, in depth lube of all fittings and cables are carried out. The D Ch