Schedule Margin

Survey of Schedule Acceleration Techniques

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Survey of 
Schedule Acceleration Techniques - An overview of schedule acceleration techniques discussed in the PASEG

The NDIA Integrated Program Management Division (IPMD) Planning and Scheduling Excellence Guide (PASEG) includes a list of the acceleration techniques that can be applied to reduce project schedule duration. That section of the guide provides the background for project team discussions on accelerating complex integrated master schedules (IMS) in government contracting environments. This blog is intended to increase awareness of the techniques in the guide and provide some additional insight into their application. It relies heavily on the guide’s content. 

An additional purpose of this blog is to promote the use of the NDIA IPMD nomenclature across the defense industry spectrum. In much the same way as the earned value management (EVM) acronyms of BCWS, BCWP, ACWP and others have become standard terminology, it would be beneficial to have a more standard way of discussing schedule acceleration techniques. As the PASEG is an industry guide developed and maintained in collaboration with U.S Government agencies, the PASEG promotes a common understanding of these techniques.

One caution. Modifications like the ones discussed here can introduce additional risk into the schedule and reduces flexibility. Be careful when modifying the schedule. A good practice is to first create a copy of the schedule and assess the effects of your changes before you adopt them. The trade-offs may or may not be acceptable depending upon the objective you want to achieve. If the schedule is the priority, there is likely to be an impact on the work scope or cost. There can also be unintended consequences when potential impacts are overlooked. 

Let’s review the techniques from the PASEG. 

  1. Crashing. 

The guide says “This technique allows for the acceleration of schedule by applying additional resources or more experienced resources to do the work in a shorter period of time. This method assumes that the task can be completed in a shorter amount of time with the increase in resources.”

We probably have all used this method when we are shopping on the internet and we are faced with the choice between receiving the item in 5 days or accelerating that to 3 days or even the next day. We are paying more to get it faster. But what is really happening behind the scenes? Do they pick your order first? Do they pack it first? Do they ship it on faster carrier? Those are the actions you would be considering on your project when you want to accelerate something by crashing the schedule.

Using outside or contract labor is a form of this where we boost our workforce for a period when we need extra effort. A form of this is offloading some work to a subcontractor.

A more detailed example comes from the factory setting where certain orders are “expedited”. What that might mean is that the normal movement process is subverted. The normal process might be as shown in Figure 1 with a queue time while your order waits for the machine. The machine will be torn down and set up for your work when it is most efficient to do so.

Process with wait time
Figure 1: Process with wait time

When you crash this process, you might simply remove the queue time so that as soon as your order arrives the machine is torn down and set up for your job to eliminate the wait time as shown in Figure 2.

Process with wait time eliminated
Figure 2: Process with wait time eliminated

However, using this approach is likely to increase cost and has the potential to introduce other risks to the project. A real-world example comes from the semiconductor industry where the factory was running both standard products and custom products. A normal custom order time of 8 weeks was cut to 2 weeks by using this approach. The cost that was charged to the customer for the rushed custom order was about 10 times the normal cost of an order to repay the factory for lost efficiency. 

  1. Fast-tracking.

The guide tells us “This technique accelerates the plan by performing work in parallel. With this method, extra attention needs to be put on resource de-confliction to ensure resources are not over allocated.”

We have all used this technique and probably had mixed outcomes. It seems simple and attractive. It embodies a “just get it done” mentality. If there are sufficient trained and capable resources then this can work. The resources can be used on both efforts at the same time. If that is not the case, then basically we would have to revert to pushing effort out of the way for another effort. This type of modification can introduce additional risk that may need to be mitigated.

  1. Streamlining.

The guide defines this technique in this way: “This technique depends on the team’s ability to find an alternate and more efficient completion methodology for the task/s. This includes reuse, innovation, and possibly eliminating non-value-added work. With this method, the program has to weigh the level of potential risk involved with these choices. Make sure that this does not drive a “run to fail” mode on the program. Ensure that tasks are meeting the full requirements and scope.”

Here we really need to be careful. In some cases, we might be working with specifications or requirements that demand a certain approach and cannot be changed or waived. Then we need to ask the question, “If there is a better way, why didn’t we assume that in the first place?”

In some cases, we might find this approach fits in with opportunity management. Maybe there is new software or a new machine available that can speed things up and still get things done correctly. We have all been in that situation; just remember the last time you went through a Windows upgrade. Did that go smoothly for you? 

In the area of software in particular, we must be aware of the entire ecosystem of tools we use and consider that any new tool applied in a hurry can result in problems. Case in point: one large contractor shifted from 2D drawings to 3D models to speed up and improve the processes, however not all the key suppliers were able to receive and use 3D models. The supply chain broke. Mom and Pop at the M&P Shop could not understand the new work orders. 

  1. Focused Work.

The guide describes focused work like this: “This technique employs the program management team to help in reducing multitasking and to remove barriers for the personnel on the program that are working critical and near critical program tasks. This method requires the program culture to adapt and “protect the critical/driving path” and to support the people that are working those efforts. This also requires the program manager to perform daily barrier resolution.”

A discussion on multi-tasking might be fun here, but we will assume for this blog that multi-tasking pulls resources away from tasks to do other selected tasks and that is not always the best approach. The big question here is what happens to the other efforts on the project when we focus on certain tasks. This technique can work well but only if we are aware of the impact to the other work and manage that work as well. Risk can be increased by adopting this approach so be alert. If we really are just removing barriers then we can benefit from this method. If we are just pushing aside other efforts to concentrate on this one, we need to know that and handle all the work properly.

  1. Calendar Adjustment.

The guide tells us, “This technique accelerates the plan by changing the amount of working hours available each day or working days available each week. This method is possible only if the resources and task location support working the increased work periods. Attention needs to be put on resource de-confliction to ensure resources are not over allocated.”

This is possibly the most attractive technique. Who has never had to resort to overtime to get something done? It is common to work extra hours, even over some weekends to get back on schedule. To a schedule practitioner, the calendar adjustment wording refers to the calendar in the scheduling tool and how it can be changed to add time in a day or convert non-working days to working days. 

This approach is not free. Overtime costs more than regular time and added shifts bring added costs. You should be aware you need to make a trade-off to determine whether the cost can be justified.

  1. Delay or Descope.

The guide advises, “If other techniques are not a viable option and the resultant schedule delay impact is unacceptable, an option exists to propose delaying or removing the selected scope.”

Notice the use of the word “propose.” Working on a contract may not afford the opportunity to eliminate work or consciously delay work. Coordination with the customer is required. Depending upon the customer’s immediate needs, they may be willing to take a more flexible approach to which work scope items can be delivered in a given time frame when they need to deploy something quickly. 

The PASEG goes on to tells us about things to promote and things to avoid. Those discussions are informative and useful. You are encouraged to obtain a copy of the PASEG and learn more on your own. More than that, you are encouraged to use this terminology and spread the use of it so that adoption spreads. 

Interested in learning more? The H&A Three Day Project Scheduling Workshop includes content on schedule acceleration techniques as well as managing schedule risk. This is a standard public workshop. Many of our clients schedule an in-house workshop that is specific to the scheduling tools they use such as Microsoft Project or Oracle Primavera P6. Call us today to get started.

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Using Schedule Margin to Increase the Accuracy of Forecast Completion Dates

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Header Image with geometric background that says Schedule Margin - Increase the Accuracy of Forecast Completion Dates

As part of our project scheduling workshops, hands-on Oracle Primavera P6 or Microsoft Project (MSP) workshops, or scheduling support assignments, we often assist clients with establishing their scheduling best practices. One of the techniques we cover in our EVM training workshops or help incorporate into our client’s scheduling process and procedures is the use of schedule margin as a means to handle schedule risks on a project. The proper use of schedule margin as well as making it a part of a project’s risk and opportunity management process can help to increase the accuracy of an integrated master schedule (IMS) to forecast milestone or project completion dates. 

What is Schedule Margin?

The NDIA Planning and Scheduling Excellence Guide (PASEG) Version 4.0 dated August 2019, defines schedule margin as “an optional technique used for insight and management of schedule risks.” Schedule margin is a period of time that is identified in the project’s plan for risk mitigation where an internal target date is set prior to a commitment date such a major project milestone or deliverable. Schedule margin is a defined task in the integrated master schedule (IMS) with logic ties (the immediate predecessor task) to a project finish milestone or intermediate decision point/milestone.

The placement and duration of the schedule margin task is based on a risk management assessment that may include a probabilistic three-point Schedule Risk Assessment (SRA). It may also be driven by schedule incentives, stakeholders needs, subcontractor interfaces, customer provided inputs, tightening of range estimates to single point estimates, or other influences.  

Some have described schedule margin as management reserve for time. A simple example would be scheduling your drive to work. Should you easily get through the traffic lights and there are no issues, you can usually make it in 30 minutes. However, because of the “risks” associated with hitting more red lights and other issues, coupled with the penalty of being late, you might plan for the trip to take 45 minutes. Those additional 15 minutes are your schedule margin.

Note however, schedule margin is not a space filler to hide positive float, a schedule stash to cover slippage, or a method used to hold an event’s date. It is a way to incorporate risk into the schedule and improve the forecast accuracy. Some government customers have refined the definition and usage of schedule margin which can impact how you incorporate schedule margin in a given project’s IMS. We will address a couple of specific government customer requirements below.

Applying the Schedule Margin Technique

The customer and contractor project manager both have a vested interest in establishing and using schedule margin. During the development of the project’s requirements definition and planning, the customer will establish need dates. Based on these need dates, target dates for key decision points/milestones are established based on an assessment of risks and constraints. Depending on the complexity, life cycle phase, and risk, the targets may be stated as a single date or range of dates. These targets are provided in the request for proposal or as guidance to the internal project team. The contractor creates a plan and estimate based on their proposal process that includes a risk management assessment. The risks that impact the ability to achieve the target dates are included in the assessment and schedule margin tasks are identified as needed.

Upon award, the contractor creates a baseline IMS with defined schedule margin tasks. These schedule margin tasks are identified as schedule visibility tasks (SVTs) within the IMS. These SVTs are usually placed immediately prior to the decision point/milestone or project finish milestone. The schedule margin SVTs do not have associated resources, they represent a time reserve. Each SVT should be clearly labeled as Schedule Margin and defined. There should be linkage and traceability between the schedule margin SVTs and the risk management plan. The customer may also identify additional schedule margin beyond the contractor’s project target dates to reflect risk to the customer need dates.

As work progresses on the project, the assessment of risks and impact to schedule margin are evaluated. Performance is measured against the baseline targets and forecasts are provided. The risk management plan is also assessed, and mitigations adjusted as needed. These assessments provide input into determining whether the schedule margin requires an updated forecast. Any changes or consumption of the schedule margin should be documented and communicated.

Specific Contracting Requirements

Know your customer’s requirements! Customers may have specific requirements related to the creation, management, and reporting of the IMS. Within the IMS requirements, the customer may have included specific guidance for the use of schedule margin. Be sure you have considered all contract clauses, data item descriptions, and statement of work requirements when planning the project. Views into the Department of Defense (DoD) and Department of Energy (DOE) schedule margin requirements are provided below. Note: we are focusing on schedule margin for this discussion and purposely avoiding other IMS related topics.

Use of Schedule Margin on DoD Contracts

Schedule margin is an optional technique used for insight and management of schedule risks. It is represented by a task or tasks within the IMS with no assigned resources and is established as part of the baseline. In a DoD contractual environment, schedule margin:

  • Resides in both the baseline and forecast schedules.
  • Should be under the control of the contractor’s project manager.
  • Is only placed as the last task before key contractual events, significant logical integration/test milestones, end item deliverables, or contract completion.
  • Is associated with schedule risk as part of a formal risk management plan.

The duration of the schedule margin task should be based on risk in subsequent events and traceable to the risk management plan. Schedule margin may be directly or indirectly connected to discrete predecessor and successor activities and fall on critical paths. All schedule margin tasks should be clearly and consistently identifiable. Schedule margin tasks should be excluded (zero duration) when performing a Schedule Risk Assessment (SRA).

Significant changes to the status of schedule margin tasks and impacts to the project’s primary critical path, if any, should be discussed in the Integrated Program Management Report (IPMR) Format 5 or the Integrated Program Management Data and Analysis (IPMDAR) Performance Narrative Report.

Figure 1 is a conceptual diagram of applying a schedule margin task before the Preliminary Design Review (PDR) milestone.

Example of a Schedule Margin Task Before a Major Milestone
Figure 1: Example of a Schedule Margin Task Before a Major Milestone

Use of Schedule Margin on DOE Contracts

The DOE has provided more specific definitions for schedule margin. They have also defined the use of DOE owned schedule contingency to buffer the schedule against unforeseen events that could cause a delay. This is documented in the DOE Guide 413.3-24 for Planning and Scheduling.

The contractor is responsible for managing their schedule margin. It resides as a single task just prior to the contractor’s project completion milestone. The DOE program office is responsible for managing schedule contingency. Schedule contingency resides after the contractor’s project completion milestone and just prior to the Critical Decision (CD) 4 milestone (Approve Start of Operations or Project Completion).

The contractor’s schedule margin and the DOE schedule contingency are both established in conjunction with CD-2 (Approve Performance Baseline), but updates may occur in conjunction with changes. The schedule margin is set commensurate with the schedule risk calculated at a probability level typically between 70 and 90 percent. The SRA accounts for risk events assigned to the contractor and contractor activity duration uncertainty. Activity duration uncertainty is determined either through a three-point duration estimate or by confidence level (high, medium, or low).

Similar to schedule margin, the DOE owned schedule contingency is set commensurate with the schedule risk calculated at a probability level typically between 70 and 90 percent. This SRA accounts for risk events assigned to DOE and DOE activity duration uncertainty.

The IMS may depict these activities as SVTs. Figure 2 is a conceptual diagram that shows the application of the schedule margin task before the contractor’s completion milestone and the DOE schedule contingency before the project finish milestone.

Example of a Schedule Margin Task and DOE Schedule Contingency Task
Figure 2: Example of a Schedule Margin Task and DOE Schedule Contingency Task

Interested in incorporating the schedule margin technique into your scheduling best practices? Call us today at (714) 685-1730. We have experienced master schedulers familiar with a variety of scheduling tools that can help you incorporate industry best practices into your scheduling process and procedures. They also well versed in applying schedule risk analysis techniques that complements incorporating schedule margin tasks into an IMS.

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