S9C4 - TASK PLANNING & CONTROL
Table of Contents
TASK PLANNING AND CONTROL
Leadership and Supervision
Task Planning Terminology
Task Assessment and Standards
Critical Path Analysis
Limitations and Constraints
Formulation of an Activity Plan
PRODUCTION PLANNING AND CONTROL PRINCIPLES
- Units shall establish task planning and control methods to maximise likelihood of success and minimise waste by accounting for:
- task complexity, criticality, interdependencies and optimum sequence for execution
- task specific limitations, constraints and environmental factors
- planning of scheduled and unscheduled activities, scalable from minor through to major tasks
- appropriate allocation of resources and execution control.
1. Task Planning and Control (TP&C) implements the overarching Integrated Activity Plan (IAP) at task level. TP&C methods detailed within this chapter and related training are essential to effective and efficient conduct of work. These contribute to well constructed maintenance events and enables confidence in safe and timely execution of the IAP.
TASK PLANNING AND CONTROL
2. The concept of TP&C is applicable across the full spectrum of maintenance activities, from a single task through to a complex scheduled servicing. Although applicable to all personnel, the act of planning maintenance tasks is the responsibility of Maintenance Managers (MM), Trade Supervisors (TS) and Self Certifying Technicians (SCT). A number of considerations to be accounted for during task planning are outlined below.
3. Each day units experience numerous maintenance events. It is equally important that minor and major activities be completed in the best possible manner to ensure the unit is functioning to its full potential. To achieve this end, TP&C concepts are scalable and applicable to any event, large or small, ensuring the optimal use of resources in achieving IAP outcomes.
Leadership and Supervision
4. Leadership style is dependent on the task context. Unit supervisors at all levels need to balance a high performance culture and the conduct of efficient operations, maintenance, supply, engineering and personnel management activities, whilst maintaining acceptable levels of safety. Increased levels of supervision may be required if personnel development is integral to the task or if abnormal factors affect the maintenance environment. These factors may include adverse weather, deployed locations or higher fatigue levels associated with high operational tempo.
Task Planning Terminology
5. To assist understanding of TP&C concepts presented in this Chapter the following terminology is used to describe the grouping of tasks.
- Sub-task – A sub-task is a piece part of another task, rather than a work package. (e.g. independent inspection of APU installation)
- Task – A task is normally the lowest level of maintenance specified in the Planned Servicing Schedule and comprises of a number of steps. (E.g. Remove APU panel)
- Work Package – Comprises of a number of tasks. (E.g. Remove, Replace and test an APU)
- Activity – Comprises of a number of work packages (e.g. A scheduled servicing)
- Event – An event is bounded by a timeframe and includes one or more maintenance activities, work packages or tasks. Events are used to control the scope of planned tasks and ensure the asset is made available for operations on time.
Task Assessment and Standards
6. An important first step in any planning activity is to understand the tasks at hand, how they relate or interact with each other and the best order in which to perform them. Even a single task may have several performance factors to consider, such as resource availability and access to facilities. As the complexity or number of tasks to be performed increases the need for a solid assessment and appreciation becomes more important. A technique known as Critical Path Analysis (CPA) can be used to identify unit task interactions, interdependencies and optimum sequencing for execution.
7. The optimum sequence for task execution should be recorded as a ‘task standard’ and where multiple tasks are conducted together, a ‘work package standard’ can be documented. Merging work package standards together form higher level ‘activity standards’. These standards also provide standard job times for planners and workforce managers to assist targeted management of underperformers and promotion of consistent high performers. Activity standards are the basis of high performing organisations and prevent re-planning for recurring tasks or groups of tasks. Standards are useful to support the cordination of resources to ensure activities are completed without undue time pressure. Ideally an activity standard should be completed within a bandwidth of 80% and 120% of the standard time. Where this is not the case investigation is warranted to determine how the activity may now be consolidated more effectively to prevent time overruns.
Critical Path Analysis
8. The goal of CPA is to identify the critical path, which is the set of tasks that must be performed in strict sequence to finish the event as soon as possible with the available resources. CPA also identifies the critical time, which is the minimum time required to complete the task. Once the critical path activities have been identified they must be carefully managed to ensure they are accomplished without extending the critical time duration. If there were no precedence relations, all the tasks could be performed simultaneously and the event would be complete when the task with the largest duration was finished. If tasks must be performed sequentially rather than in parallel, then the event completion time is the sum of the task times. Generally, activities will comprise a mixture of serial and parallel tasks that have precedence relations restricting the order of conduct. CPA allows managers to set due dates, organise the means of production, schedule the need for resources and track progress against activity standards. CPA is applicable for even the simplest of tasks as displayed in Figure 1 (This example is deliberately sub-optimal to provoke thought).
Figure 1 - Example of Critical Path for Simple Maintenance Task (Sub-optimal)
9. CPA is particularly beneficial when planning large maintenance events that are complicated by limited resource availability. The information yielded from CPA provides the foundation for schedule preparation, resource planning and allocation, which serves to de-mystify the planning process. It is important to reassess the critical path after any change to plan or schedule and adjust as necessary
10. Activity Precedence Relations. Any maintenance event will have sequential and/or parallel task relationships to the other tasks within the schedule:
- Series dependency. A series dependency exists between tasks where a previous or subsequent task has a dependency with the start or completion of the subject task respectively. These dependencies generally have the greatest influence on total time for the event and may form part of the critical path.
- Parallel tasking. Parallel tasks may be completed concurrently with tasks that do not create conflict, however may have a series dependency with other tasks in the schedule. Generally, the more parallel tasks there are, the shorter the event timeframe. The completion of parallel tasks does remain dependant on availability of resources.
- Float tasks. Float tasks are a subset of parallel tasks and generally have no dependences. These can be accomplished at any time without affecting the schedule and provide an excellent opportunity for workforce load levelling.
- Exclusive tasks. Exclusive tasks are those that require complete exclusion of other work being performed concurrently (e.g. No application of power during fuel tank entry). Exclusive tasks will likely form part of the critical path in the plan.
11. Series, parallel, float and exclusive tasks need to be identified and scheduled to enable optimal execution of maintenance events. Refinement of task scheduling and recording of lessons learned in activity standards will occur over time, with repetition of successive maintenance tasks. These terms and skills must be familiar to all unit tradespersons and engineers, which enables a high degree of understanding and professionalism in further senior positions such as WOE and SMM.
12. A consideration when carrying out CPA for scheduled maintenance activities is the inspection phase. Inspection will often yield emergent work which can significantly alter the critical path of the activity and may require additional spares or engineering decisions. Due to this potential, identification of emergent work impacting the critical time will need to be included in the critical path of an activity standard. If detected early through inspection, these additional tasks can be actioned in parallel rather than necessarily impacting the critical path.
Limitations and Constraints
13. Effective task planning requires an understanding of aggregate limitations and constraints associated with the task. These include:
- hardstand weight loading
- wind speed for jacking
- sequence of work
- programming and rostering personnel
- appropriate preparation for hangar entry
- factors unique to trades and local environment
- periods of power on/off
- hydraulics on/off
- engine running
- towing/transit time of asset resources
- constraints as identified within regulatory and platform specific maintenance documentation
- activities that require multiple systems to be operated .i.e. autopilot functional tests.
14. To ensure TP&C is able to effectively implement the IAP, the unit must be adequately resourced. Resource requirements can be identified in advance for the conduct of maintenance, allowing for inclusion in task planning. Questioning resource management practices that do not deliver safety or productivity will assist in identification and reduction of waste. Resourcing includes, but is not limited to:
- Task Teams. Unless an SCT is performing a task there will be a requirement to form a team, the composition of which will be determined by balancing task and training requirements. The team size and skills-set must align with the volume and skill level of maintenance to be performed. Incorrect team allocation or composition can result in inefficiency, waste (e.g. manpower and financial cost) or unsafe practice. The following provides an outline of considerations when formulating team composition and size:
- supervisory requirements
- training requirements and authorisation of tradepersons
- development of capability enhancing options, such as SCT
- costs and benefits of using/procuring support equipment versus the use of additional manpower
- assurance that airworthiness and safety requirements are maintained
- measurement of resource cost per hour and hours of effective usage to inform future planning. In support of cost analysis, PACMAN Vol 1 Chapter 3.1.1 Part B provides cost breakdowns per rank/employment group. These costs can be used to inform cost-benefit analysis such as that identified in paragraph 12b.
- Workspace Layout. An optimised workspace layout will maximise work flow and minimise waste through travel-time, supported by appropriate location of tools, authorised maintenance data, spares, workspaces and amenities. Where this is not the case, investigation and action to remediate is warranted on the basis of a cost benefit analysis (e.g. a reduction in man hours can be achieved through a workspace modification that demonstrates a return on investment).
- Support Equipment. S&TE, GSE and safety equipment is to be programmed for tasking. Priority tasking identified by Critical Path Analysis (CPA) takes precedence when multiple tasks require the same equipment concurrently. The application of TP&C will mitigate availability risk of these resources. Early engagement with support equipment personnel via the Principal Maintenance Coordinator (PMC) will ensure timely availability of necessary equipment.
- Tools. All tools required for the maintenance activity must be serviceable and made available for use. Tool selection best practice to obtain all necessary tools on the first visit to the tool board improving productivity through reduced travel time. Consider the use of mobile Composite Tool Kits commensurate with the size and duration of the task.
- Authorised Maintenance Data. Access to required maintenance publications for the activity must be assured prior to commencement. Where workflow inefficiencies are identified through analysis of activity standards, publication improvement requests will ensure safety and productivity benefits are captured in authoritative documentation.
- Spares. Forecasting and ordering of spares for scheduled maintenance is to occur at the earliest possible opportunity to minimise downtime, maximise productivity and reduce administrative overheads. Best practice is to draw the correct number of spares needed and track quantities before and after the task. Timely assessment of spares requirements for unscheduled maintenance events including justifiable prioritisation of demands will reduce completion time for maintenance tasks.
15. The situation within which maintenance is conducted can vary greatly depending on location and prevailing environmental conditions. Some considerations include:
- Home Base Operations. Where facilities, tooling, GSE and support arrangements are specifically set up to conduct maintenance of the applicable platform.
- Away/Forward Operating Base Operations. Where environmental factors may be similar to home-base operations, however, they differ in their structure and support mechanisms.
- Deployed Operations. Where there may be limited facilities or support mechanisms with the only support available being deployed with the platform.
- Inherent in previous paragraphs a - c. Climatic conditions may vary considerably and have a significant impact on unit activities.
- Common Deployment Practices. Practices employed from previous deployments are duplicated for ease of start-up without critical review. This is characterised by ‘that’s the way we’ve always done it’ practices. The more resource intensive an activity is, the more likely improvements can be identified.
16. Maintenance requires a methodical approach to achieve optimum results. The phases below are typically applicable to any maintenance activity:
- Planning. Planning is an essential phase for any task regardless of complexity or duration. Benefits from deliberate planning include prevention of safety occurrences and enhanced performance. A task planning sheet template and planning guidance can be found via the Maintenance Operations ToolBox, which may enhance task planning processes within the unit. Reference to pre-existing activity standards serves to shorten the time needed for planning.
- Fault Diagnosis and Finding. This phase normally occurs during unscheduled maintenance, however may be performed at any time to identify the root cause of component failure or incorrect system functionality. Effective fault analysis is vital to correct fault diagnosis prior to rectifications being initiated. Supervisors must monitor and record fault finding as a portion of the rectification time to identify where further resources, refresher or remediation training is necessary. Robust fault finding abilities reduce variability in establishing task completion timeframes and success in achieving those timeframes.
- Drawing of Resources. The prior identification and timely demanding of spares, tools, authorised maintenance data and S&TE, including specific quantities of each is vital to the successful completion of the task. Accounting and control of these resources throughout the task is vital to maintaining safety and achieving good performance.
- Tear Down. This phase involves removal of panels, inspection covers and Repairable Items (RIs) to enable access, or inspection, of required areas for maintenance activity. To assist capture of emergent maintenance, it is vital that all items removed are thoroughly inspected for signs of damage, corrosion and poor surface finish.
- Inspect. A thorough system or platform inspection conducted to identify faults or emergent work requiring rectification. Examples include out of tolerance corrosion, cracks, chaffing, leaks and damage to structural components or RIs. The inspection phase will likely necessitate additional resources required to undertake the repair of emergent work. Rectification of this emergent work must be recorded in the activity plan to ensure its impact on the critical path is understood and minimised.
- Reporting. Concurrent with inspect phase is consideration for submission of engineering reports (e.g. Non-compliance Report and Disposition, Deficiency Reports, Defect Reporting). These reports highlight tasks requiring support agency disposition and timely submission will provide a realistic timeframe for investigation and response. The requested ‘due by’ date on such submissions must realistically describe the effect on the task’s critical path.
- Rectifications. The process of conducting work to:
- rectify a particular fault
- complete activities associated with the particular event
- rectify any emergent work
- implement and complete other outstanding activities such as incorporation of Modifications, repair or replacement of subcomponents (MMIs, spares), Deferred Maintenance, and STIs.
- Rebuild. Elements of this phase may occur coincident with the "Functional Tests" phase (below). This phase involves:
- reassembly of systems and subsystems
- conduct of work to restore the asset to a serviceable condition including reinstallation of panels, inspection covers and RIs.
- Functional Tests. As systems and subsystems are reassembled to a serviceable condition, tests are conducted to verify the correct function of each system. Elements of this phase may occur coincident with the "Rebuild" phase, described above.
- Maintenance Ground Run and Maintenance Test Flight. Once the asset has been serviced, is fully assembled and has undergone functional testing, it may be required to undergo a ground run and/or a post maintenance test flight. This confirms that systems requiring operational testing are performing as designed and are fully serviceable.
- Recording Completion of Maintenance. Provided successful testing is completed, relevant documentation must be certified and forwarded to appropriate section (e.g. Maintenance Control Office (MCO)) for recording and retention.
- Return of serviceable materiel. The unused and/or serviceable materiel drawn in paragraph c is to be returned prior to the commencement of a new task.
- Disposal of unserviceable materiel. Unserviceable materiel drawn in paragraph c must be disposed or returned in accordance with eSCM and WHS requirements.
- Return of Unserviceable Resources. The timely return of unserviceable RIs, tools, authorised maintenance data and S&TE by unit personnel directly affects future availability of serviceable assets. Critically managed items require priority return to the repair pipeline.
- Debriefing. There is a need to debrief all tasks, as there is merit in correcting behaviours and acknowledging achievements of the members involved. A debrief sheet would aid this process and examples are provided on the Maintenance Operations ToolBox. Updating the applicable activity standards with lessons learned must be conducted at the completion of maintenance.
17. Task planning must occur for all scheduled and unscheduled maintenance events. The nature of scheduled maintenance presents greater opportunity for deliberate planning in advance and therefore these tasks have a higher degree of certainty. The following considerations should be included whilst planning maintenance activities.
18. Commencement, Completion and Progression Reporting. The commencement timeframe for maintenance tasks is provided by the PMC for scheduled and unscheduled maintenance. For scheduled activities, this date is usually known in advance and presents greater opportunity in task planning. The commencement date/time for work on unscheduled maintenance will come from the PMC and will be a deliberate decision to expend manpower and resources on the activity to satisfy operational tasking. There will often be little lead time on unscheduled maintenance tasks but this does not devalue the importance of planning.
19. The completion date/time is the pre-determined date/time by which the asset must be made serviceable to meet operational requirements. The completion date/time is estimated via activity standards, CPA and experience. The completion date/time is used in planning to determine the amount of workforce capacity required to meet the target.
20. Progress reporting is essential to ensure the PMC is aware of progress to plan, which allows the PMC to allocate extra manpower or resources where needed or to swap operational requirements to other assets if required. To assist analysis of maintenance performance, a log (electronic being preferred for archiving purposes) of daily work accomplished should be captured. This log will be utilised to document progress of the activity (against the plan), and measure overall success of maintenance planning. Information collected within the log will be used to enable performance analysis, assisting continual improvement.
21. Maintenance Forecast. When conducting planning for scheduled maintenance it is essential that maintenance forecasting for the asset be conducted prior to the planned induction date/time. Maintenance forecasting leads to the identification of any additional tasks to be performed concurrent to the planned activity. The maintenance forecast must cover the planned completion date and out to a PMC pre-determined post completion date. This generates a maintenance tasking picture, which provides an indication of activity scope and duration. For long duration unscheduled maintenance events there may be opportunity to concurrently replace components which are close to falling due, thereby reducing future down time.
Formulation of an Activity Plan
22. Unscheduled Maintenance. Irrespective of the complexity and duration of unscheduled maintenance an activity plan must be developed. Even the simplest of tasks will benefit from a degree of planning and as complexity increases the need for further detail in the plan increases. For simple work packages the plan may be informal, however, complex activities covering multiple shifts will require formal planning. The plan should cover considerations such as:
- start time
- target completion time
- workforce and other resources required/allocated to tasks
- training opportunities for team members
- fault finding/identification plan (if required)
- identification of Critical Path activities using activity standards or CPA
- allocation of team members to activities based on activity standards or CPA
- plan for briefing team members on the sequence of activity execution
- spares required and lead time
- tools required
- GSE and ST&E required
- facilities required (hangar, etc)
- schedule for reporting progress to PMC or delegate
- maintenance documentation – entries in documentation such as “No Power to be applied”, “No Hydraulics to be applied”
- inspection requirements and availability of personnel
- potential for the activity to span more than one shift driving certification of maintenance and targeting of a logical safe hand over point
- requirements for other trades to perform supporting activities such as engine runs.
23. As experience on a particular asset type increases over time, many unscheduled maintenance events can be anticipated depending on mission profiles, environment and other local factors. Some preplanning for potential unscheduled events can be done in advance, thereby reducing planning time if the failure occurs. Unscheduled activity standards should be developed in anticipation of recurring unscheduled unserviceabilities, therefore diminishing the impact of reduced notice for task planning. Pre-positioning resources can also assist in reducing rectification timeframes. The development of fly away kits also requires this kind of risk-based predictive planning for the conduct of successful deployments.
24. Scheduled Maintenance. Scheduled activity plans must be documented using an activity standard in advance of commencement. As a minimum, the activity standard should detail the following:
- An induction date and a PMC provided completion date, which must include an allocation of time for emergent work from the inspect phase. The completion date/time may be sooner or later depending on emergent work discovered during the inspect phase and is altered once scope of emergent work is understood. Duration data should be recorded for typical maintenance activities and be used to predict a bandwidth of likely completion dates for similar future activities.
- An outline of tasks against a timeline which identifies the critical path and concurrent tasks for the activity.
- Identification of limitations, constraints, environmental factors and resources to complete the activity.
- A complete list of engineering, maintenance, supply and operational tasks and equipment needed for completion of the activity including:
- routine servicings
- special servicings (due, advanced, and/or extended)
- deferred maintenance
- Special Technical Instructions
- Maintenance Interval Extension Request (MIER) related penalty maintenance
- Maintenance Managed Items (MMI) due for servicing
- reconfiguration or role equipment
- operations staff liaison and advice
- GSE and ST&E (including special support equipment not typically utilised during conduct of maintenance) required to complete the activity
- supply personnel liaison and lead time advice related to RIs and spares required to support all above activities.
25. TP&C methodologies allow implementation of multiple concurrent tasking within the scope of an IAP. Successfully meshing and de-conflicting these tasks requires collaboration of unit functions including:
- Operations Plan. Formulation of the Operations plan, derived from the daily operations program following allocation of suitable assets and creation of a work plan.
- Supply. Management of spares demands to match the IAP in advance, return of unserviceable items to store and consumable item replenishment.
- Maintenance. Section workforce plans, individual task plans and scheduled servicing plans that are linked to achievement of the IAP.
- Maintenance Support. Quality management, safety, unit training and governance requirements.
- Engineering Support. Deferred maintenance authorisation and review, oversight of technical investigation and reporting (e.g. Defects, MIER, MDR, NCRD and ASOR), including negotiation of support agency requirements.
- Operations. Executing the plan and early negotiation of changes. Provision of accurate fault symptoms to assist with diagnosis and timely rectification.
- External Support Elements.Elements to support the achievement of the IAP (e.g. Base Fuel Facility, Air Movements, Air Traffic Control, Base Security and Fire Section). This requires the unit to communicate relevant IAP requirements to enabling agencies with sufficient lead time.
- Internal Support Elements. Personnel management including leave, travel and passport management, pay and allowances, deployment accommodation and transport arrangements.