Task Scheduling Example

Given this information derived from a Work Breakdown Structure

Activity
 Immediate Predecessor
 Estimated Days
A
 -
 5
B
 -
 4
C
 A
 3
D
 B
 7
E
 C
 2
F
 D,E
 1

1. Draw the corresponding task network diagram:

task network

Now that we see the dependencies visually, it's easy to determine start/finish dates.

2. Create a table of this information:
Activity
 Earliest Start
 Earliest Finish
A
 1
 5
B
 1
 4
C
 6
 8
D
 5
 11
E
 9
 10
F
 12
 12

From this we can conclude that the project will take a minimum of 12 days.

3. Next transform this into a timeline chart but don't worry about real-life dates yet.

    1 2 3 4 5 6 7 8 9 0 1 2 3 
A   [ - - - ]
B   [ - - ]
C             [ - ]
D           [ - - - - - ] 
E                   [ ]
F                         []

 4. Now map the above chart onto an actual calendar, say Feb 5, 2003.
                       
              1                   2
    5 6 7 S S 0 1 2 3 4 S S 7 8 9 0 
A   [ - -     - ]
B   [ - -     ]
C                 [ - ]
D               [ - - -     - - ] 
E                           [ ]
F                                 []


 From this we can determine that the earliest we'll be done is Feb 21.

5. Using a tool such a Gnome Planner, you can omit steps 3 and 4 and create a Gannt chart directly.  The tool shows the critical path with arrows, and slack times are shown in green.


Gantt solution