Fast Tracking and Crashing both are two key Project Schedule Compression techniques.
But, What is Project Schedule Compression ??
In simple words, Project Schedule compression is reducing the duration of a project schedule, without compromising on the work that needs to be done in that schedule.
PMBOK says Schedule Compression techniques are used to shorten the project schedule duration without reducing the project scope, in order to meet schedule constraints, imposed dates, or other schedule objectives.
Schedule compression is required when your project is delayed and needs to be brought back on track (schedule).
Major reasons for project delays
Delays can occur to a project due to various reasons, but some common reasons are below
- Unavailability of resources – This is one of the major reasons and the higher management also has a play in this.
- Risks – Improper management of known risks, and Occurrence of unknown risks.
- Unrealistic schedule
- Force Majeure – It is a common contractual clause that frees parties, bound by a contract, from liability or obligation if an “Act of God” happens.
- Pressure from higher management for new business opportunities – This happens when the higher management sees the possibility of getting a new business or project if you can complete this project early.
- Need to launch the product early – this can happen when a competitor launches a rival product and you can’t afford to lose the market.
- etc…
Key Project Schedule Compression Techniques
There are 2 two key project schedule compression techniques that are widely used.
- Fast Tracking
- Crashing
Fast Tracking
As per the PMBOK Guide, 6th edition, fast-tracking is a schedule compression technique in which activities or phases normally performed in a sequence, are done in parallel for at least a portion of their duration.
With this technique, activities or phases normally done in sequence are performed in parallel, for at least a portion of their duration.
In the above example, activities B & C are performed in parallel, thus reducing the overall project duration to 40 from 60.
The above is a very simple example of how project schedule compression is done with Fast tracking.
In Fast Tracking, you first review the Critical path. Analyze and Identify all the activities that can be performed by overlapping (partially or fully) with other activities without compromising the Project Scope.
Fast tracking is not done to activities that are not on the Project Critical path, because they all have float, and consequently fast tracking them will not have affect on their duration.
It is important to understand that, Fast Tracking can be done only when the activities can be overlapped with out compromising on scope.
One key aspect of Fast tracking, when compared to Crashing is that No additional resources are used in fast tracking process.
Further, a drawback of Fast tracking is, it often results in Rework and Increased Risk. Further, it is important to understand that fast tracking helps you compress schedule up to a certain limit, but If you go compressing beyond the limit, risk increases and possibility of rework increases.
Crashing
The key aspect in this technique is, additional resources are used to do things more quickly, there by reducing the schedule duration.
PMBOK says that Crashing is used to shorten the schedule duration for the least incremental cost by adding resources.
Examples of crashing
- Bringing in additional resources,
- Approving overtime,
- Buying a software to do the work,
- Paying extra to expedite delivery of the required activities.
- etc..
It is important to understand that Crashing works only for activities on the critical path where additional resources will shorten the activity’s duration.
To do Crashing, you first review the Critical path. Analyze and Identify all the activities that can be completed early with the help of extra resources. Identify the activities that provides the highest compression at the least possible cost.
It is observed that the level of compression per unit cost that can be achieved on an activity is not uniform, but increases over a period of time. In such a situation, do a Cost-Benefit Analysis and proceed.
Further, Crashing does not always produce a viable alternative and may result in increased risk and/or cost.
Differences between Fast Tracking & Crashing
SUMMARY
Projects are often delayed and there are various reasons for that. In such cases you need to compress the project schedule duration in order to bring the project back on track. Fast tracking and Crashing are techniques used to compress project schedule. In Fast tracking activities or phases normally done in sequence are performed in parallel, for at least a portion of their duration. Fast Tracking does not involve costs, but may result in risks and rework. In Crashing, additional resources are used to do things quickly, there by reducing duration. Crashing does not result in too much risks, but it involves cost.