Critical path analysis

Question 1

Define CRITICAL PATH ANALYSIS

Answer 1

Critical path analysis is a technique used to identify the order in which all activities need to be completed when planning a complex project.

Question 2

Define a CRITICAL PATH

Answer 2

A critical path is the set of tasks that will prolong the duration of the project if delayed.

Question 3

How is a critical path model drawn?

Answer 3

1. Identify all the task that need to be completed.
2. Identify how long each task will take.
3. Identify when each task is able to start, making note of any dependencies. List all this information in a table.
4. Draw circular nodes to show when a task is ending or beginning.
5. Write the name of the task above the line and the length of the task below it.
6. ESTs go in the top right hand quadrant of each node, with LFTs going in the bottom right.

Question 4

Define an EST

Answer 4

An EST is the earliest time that a task can start. They go in the top right hand quadrant of the node, to the left of the task.
To calculate: go from left to right, adding the duration of the task to the previous EST.

Question 5

Define an LFT

Answer 5

An LFT is the latest time that a task can finish without delaying the next task. They go in the bottom right hand quadrant of the node.
To calculate: work from right to left. Subtract the duration of the activity from the previous LFT. If there is more than one answer, write down the lowest result.

Question 6

Define FLOAT

Answer 6

Float is the spare time that arises between the completion of an activity and the starting time of the next activity.
To calculate: LFT - duration - EST

Question 7

What are the advantages of critical path analysis?

Answer 7

• Identifying the critical path helps to speed up the time take to complete the project, leading to possible competitive advantages.
• Speeds up product development, which could lead to a first mover advantage.
• Improves working capital by reducing cash tied up in stocks (JIT/lean production)
• Improved efficiency leads to lower costs, leading to higher profit margins.

Question 8

What are the disadvantages of critical path analysis?

Answer 8

• Reliability depends on the accuracy of the data used.
• Managers must ensure that estimated times are actually achieved - links to HR issues like motivation or trade unions.
• Estimates are vulnerable to external factors, like delivery delays.