PMP: Crashing vs Fast Tracking

• Crashing: crashing is a schedule compression technique to shorten the activity duration by adding extra resources (money and/or human resources)
  • involves additional costs as extra resources are needed for
    • overtime
    • extra manpower
    • outsourcing
  • normally to be explored after Fast Tracking
  • Project Manager needs to judge which activities can be “crashed” with the lowest cost for the maximum effectiveness
  • may create risks for rework/defects

(Image credit: greycampus.com)

• Fast Tracking: is a schedule compression technique to perform activities in parallel (partial or in whole) in order to save time
  • the activities to be performed in parallel should be analyzed for logical relationship and that the two activities in question can really be carried our in parallel (i.e. overlapping of part or the whole activities)
  • normally no extra resources are needed
  • additional risks may be created
  • Fast Tracking is the preferred method for schedule compression

(Image credit: greycampus.com)

Both Fast Tracking and Crashing must be applied to activities on the Critical Path in order to really shorten the project duration. When applied on activities not on the critical path, it would only increase Floats which will not shorten the project duration (note: the Critical Path may be different when there are delays to activities of the project).

Conclusion:

Crashing and Fast Tracking are the two most common schedule compression technique to shorten the project duration in case of delays while preserving the project scope. Fast Tracking is to carry out activities originally in sequence to be in parallel (partial or whole) while Crashing is to add extra resources to shorten the normal duration of the activities.

Fast Tracking is preferred over Crashing as the former does not involve extra resources and costs which would affect the project budget performance. However, it is important to note that both Fast Tracking and Crashing creates risks for rework (otherwise this would have actually been incorporated into the Project Plan at the very beginning) which needs to be carefully balanced with the benefits of schedule compression.

For information, another effective schedule compression technique is to trim down the project scope, but this would likely affect the project objectives and thus is not the preferred way to go.