Question

Your boss wants you to propose ideas on how to significantly cut the schedule on a project (e.g. crash the schedule) by reallocation of resources. Explain the notion of “crashing a schedule” and how one can determine if investments require will have any positive effect at all.

Answer 1

1. There are two recommended techniques to compress the schedule of a project. They are:

a. Crashing the project

b. Fast Tracking the project

2. Crashing means addition of resources whereas Fast Tracking means performing some activities of the project in parallel.

3. Fast Tracking usually increases project Risk while Crashing increases project cost.

Since, the boss has asked me to cut the schdule by reallocation of resources, I would do the following step-wise:

1. Make a table of all activities, their predecessors, duration and resources required for each activity.

2. Make a project network and represent it using Activity on Node graph.

3. Determine the Critical path, which takes the longest time.

4. Review whether the completion time required is less than critical path time or not. If yes, then would not do anything. If not, would look into the resource allocation.

5. If the project has already started, I would review the complete resource allocation and determine "slacks" for each activity.

6. Review the additional resources allocated to those activities which have slacks, starting from the highest slack to the lowest slack, but all slack > 0, since slack = 0 for critical activities.

7. Check if the resources removed from non-critical activities can be used for critical activities. This is called "resource allocation" in this context. Thus, I have "crashed" the project by putting "additional" resources to critical activities by removing those additional resources from non-critical activities.

8. If some critical activities remain where the "additional" resources, removed from non-critical activities, cannot be assigned, I would look for hiring additional resources at additional cost/investment and look at the amount of time that can be crashing for each activity.

9. In the same table (as in Step 1), I would write down th Crashing Cost per resource and Maximum Time by which an activity can be crashed.

10. Start crashing the activities on the "critical path" (which have slack = 0), starting with the least expensive activity (which has the least crashing cost per resource) and ending with the most expensive crashing cost activity.

11. Determine after crashing each activity whether (and these are the two objectives I am working with):

a. My target schedule is met or not. If met, STOP crashing more activities. If not met, continue.

b. No other non-critical activity becomes a critical activity.

12. Continue the above steps 10 and 11 till I reach any of the two objectives stated above.