Aircraft Maintenance has evolved with time. Initially, maintenance was mostly reactive. What fails would be fixed. Gradually, a concept called Built-in test equipment (BITE) was introduced which refers to passive fault management and diagnosis equipment built within the module to support maintenance.
Primary maintenance processes can be broadly classified into three groups namely Hard time (HT), On condition (OC) and Condition monitoring (CM). While the HT works on preventive methodology, OC & CM works on predictive methodology. An effective Aircraft Maintenance Program (AMP) would be a combination of all these monitoring processes depending on the type of component/system being looked upon.
Systems have become so sophisticated that one should be aware of the emerging technologies. Online aviation maintenance courses concentrate on such emerging techniques.
Engine has rotating parts. In case of any unbalanced distribution of rotating masses around an axis of rotation, it leads to bearing failure. Engine repairs are expensive.
Engine Vibration Monitoring (EVM) Systems measure rotor out of balance information which can be corrected in accordance with the Engine Maintenance Manual (EMM).
Engine condition Trend Monitoring (ECTM) provides important information about engine condition. This is also called Engine Health Monitoring (EHM). The aim is to capture any defect before it proliferates and this helps in cost associated with expensive repairs. This process will help in huge savings to the company. As an OEM, the findings could improve the new design by accommodating research on the drawbacks noticed.
ECTM is an activity of using engine data to find symptoms of damage, deterioration, or excessive wear of some of the rotating components. Engine must be continuously monitored to maintain the health of its components. The computation involves the combination of aircraft parameters and engine parameters. The parameters being measured are not standard across all engines. It depends on the availability of sensors. Modern engines have many sensors which directly transmit data to the cloud and provide real time solutions. This involves data analytics. Data analytics make flying safer.
Predictive maintenance is not restrictive to the engine alone. Any part of the aircraft system can fail to operate. Depending on the relevance and importance, the Standard Operating Procedure (SOP) might recommend cancelling the planned flight until the issue is fixed. This can be an unplanned grounding and such a maintenance activity is called as unscheduled maintenance.
Unscheduled maintenance has many outcomes.
Aircraft on Ground (AOG) situations
Inconvenience to passengers
Reputation of the airline is at stake.
Predictive maintenance is one of the solutions to reduce unscheduled maintenance, and this is an integral part of online aviation maintenance courses.
If Proactive is to identify safety concerns before the event, Predictive is a method to anticipate future exposure based on past performance data. While Big data is used to make data driven decisions, Predictive analytics is for the risk evaluation and prediction of future outcomes
by Sumanth Eswar
Ex Assistant Manager-Technical Services, Jet Airways
14 years of industry experience in various sections under Engineering and Maintenance department such as Engineering Planning, Technical Services Engineering including Structures, Cabin Maintenance, Airframe and Systems, Base Maintenance, Powerplant, Reliability, Aircraft Weighing, Rotable Management. Years of Safety Office experience and was a surveyor for Aircraft Insurance