AIRCRAFT MAINTENANCE

1. AIRCRAFT MAINTENANCE Continuing analysis and surveillance system (CASS) Reliability& Safety

2. Reliability Definition • “The probability that an item will perform a required function, under specified conditions without failure, for a specified amount of time.” 2 Main Approaches • Looks at Whole Operation : Dispatch Reliability • Looks at Maintenance Program : Reliability Program

3. Reliability Term Reliability • Overall Reliability • Component Reliability • Process Reliability • Maintenance Program Reliability Types of Reliability (4 types) • Statistical Reliability • Historical Reliability • Event-oriented Reliability • Dispatch Reliability

4. Reliability Event-oriented Reliability • Concerned with one-time events such as bird strikes, hard landing, in-flight shutdowns, or others accidents or incidents, which these are events that do not occur on a regular basis. • Each occurrence must be investigated to determine the cause and to prevent or reduce the possibility of recurrence of the problem.

5. Reliability Dispatch Reliability (DR) • DR is a measure of the overall effectiveness of the airline operation with respect on-time departure. It is a simple calculation based on 100 flights. • DR involves more than just maintenance • Dispatch delays should look at the whole operation. • On-time departure means that the aircraft has been “pushed back” from the gate within 15 minutes of the scheduled departure time

6. Reliability Dispatch reliability

7. Reliability Reliability Department • Responsibility of monitoring failure rates, removals of A/C systems and components to measure the effectiveness of the overall maintenance program • Data Collection • Preliminary Investigation • Issue Alert Notices • Monitor Results

8. Reliability Reliability Program • A set of rules and practices for managing and controlling a maintenance program • Monitor the performance of the vehicles and their associated equipment and call attention to any need for corrective action • Monitor the effectiveness of corrective actions • Provide data to justify adjusting the maintenance intervals

9. Reliability Elements of a Reliability Program • Data collection • Problem area alerting • Data Display • Data analysis • Corrective actions • Follow-up analysis • Monthly report

10. Reliability Data collection • Flight time and cycle • Cancellations and delay over 15 minutes • Unscheduled component removals • Unscheduled engine removals • In-flight shutdowns of engines (IFSD) • Pilot reports or logbooks • Cabin logbook • Component failure (shop) • Maintenance check package findings • Critical failures ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis ▪Monthly report

11. Reliability Problem area alerting • An alerting system • Identify those areas where the performance is significantly different from the normal • Alert level is based on a statistical analysis • Alert level is set at one to three standard deviations above the mean rate • Alert level is referred as UCL (Upper Control Limit) • Additional calculation that can be made to smooth the curve (3 months average) and help eliminate “false alerts” ▪Data collection▪Problem area alerting▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis ▪Monthly report

12. Reliability Problem area alerting (cond.) • Setting and adjusting alert levels • Recommended that alert levels be recalculated yearly UCL (Upper Control Level) 3 months Offset Control Chart ▪Data collection▪Problem area alerting▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis ▪Monthly report

13. Reliability Data analysis • Reliability Department • a preliminary analysis to determine if the alert is valid • If valid, on-alert condition is sent to engineering for a more detailed analysis • Engineering Department • Troubleshoot the problem • Issue EO (Engineering Order) • Recommendations to the Airline Maintenance Program Review Board (MPRB) ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis▪Corrective actions ▪Follow-up analysis ▪Monthly report

14. Reliability Corrective actions • Modifications of equipment • Correction to line, hangar or shop processes or practices • Disposal or defective parts • Training of mechanics • Addition of maintenance tasks to the program • Decreased in maintenance intervals Completion of the corrective action is noted in the monthly reliability report ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis ▪Corrective actions▪Follow-up analysis ▪Monthly report

15. Reliability Follow-up analysis • Verify the corrective action taken was indeed effective • Reflected in decreased event rates • If no significant change, corrective action should be reanalyzed ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis▪Monthly report

16. Reliability Monthly report • Working tool for maintenance management • Picture of what problems are encountered ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis ▪Monthly report

17. Reliability Reliability Program Document • Every aspect of the reliability must be documented in an official document signed be MPRB chairman and approved be the regulatory authority • Include: • Detailed discussion • Methods used to determine alert levels • Rules relative to changing • Define MPRB activities and Responsibility • Monthly Report Format • Submitted to FAA for approval ▪Data collection▪Problem area alerting ▪Data Display ▪Data analysis ▪Corrective actions ▪Follow-up analysis ▪Monthly report

18. Safety

19. Traditional Safety Management • Loss Control - Correction approach • Loss control is the tools for - Prevention - Reduction - Elimination • Cause of incident and accident is -Unsafe Action -Unsafe Condition

20. Loss Causation Model 1. Loss - Loss of Direct cost - Loss of Indirect cost 2. Incident 3. Immediate Cause - Low standard action and Low standard condition 4. Basic Cause - Personal Factor and Job Factor 5. Lack of Control

21. Loss Control Management Process • Identification of Work • Set Standard • Measurement • Evaluation • Commendation and Correction

22. Modern Loss Management 1. Source of Loss - People - Equipment - Material - Enviroment 2. Loss Control systems - International Safety Rating System (ISRS) -US - Total Loss Control Management-UK

23. Modern Safety Management • Modern Safety Management – Prevention, Risk Assessment and Risk control approaches • Modern Safety Management is Loss Control Management • Modern Safety Management used POLC framework

24. Modern Safety Management • There are 4 approach to Modern Safety Management • 1. Management concept • 2. Management information system • 3. Performance standard • 4. Measurement and Evaluation system

25. System Safety

26. FAA - Safety Risk MatrixFAA Advisory Circular No. 120-92, Introduction of Safety Management Systems for Air Operators

27. FAA - Safety Risk Matrix • Unacceptable (Red). Where combinations of severity and likelihood cause risk to fall into the red area, the risk would be assessed as unacceptable and further work would be required to design an intervention to eliminate that associated hazard or to control the factors that lead to higher risk likelihood or severity. • Acceptable (Green). Where the assessed risk falls into the green area, it may be accepted without further action. The objective in risk management should always be to reduce risk to as low as practicable regardless of whether or not the assessment shows that it can be accepted as is. This is a fundamental principle of continuous improvement. • Acceptable with Mitigation (Yellow). Where the risk assessment falls into the yellow area, the risk may be accepted under defined conditions of mitigation. An example of this situation would be an assessment of the impact of a non-operational aircraft component for inclusion on a (MEL). Defining an Operational (“O”) or Maintenance (“M”) procedure in the MEL would constitute a mitigating action that could make an otherwise unacceptable risk acceptable, as long as the defined procedure was implemented. These situations may also require continued special emphasis in the safety assurance function

28. General Safety Rules • Fire prevention & protection • Hangar deluge systems • Fall prevention and Protection • Storage and handling • Smoking regulation • Hangar safety • Shop safety • Line safety

29. Hand Signal

30. Safety Management System • ICAO has established a framework for an SMS that incorporates four basic components and 12 elements as shown here:

31. MEDA Corrective Actions

32. THE END