Crashing and Overtime Scheduling in a Project

The project has been crashed, reducing the activities' duration to a total of 13 days. The use of overtime can be applied to reduce the cost expense and help reduce the duration, bringing the project within a 12-day target without using crashed durations.

1.
Task Name Duration Start Finish Predecessor
s
Early
Start
Early
Finish Critical Free
Slack/Float
LaunchProjec
t 16 days
Thu
22-12-
16
Wed
12-04-
17
Thu
22-12-
16
Wed
12-04-
17
Yes 0 wks
A 3 wks
Thu
22-12-
16
Wed 11-
01-17
Thu 22-
12-16
Wed 11-
01-17 Yes 0 wks
B 5 wks
Thu
12-01-
17
Wed 15-
02-17 2 Thu 12-
01-17
Wed 15-
02-17 Yes 0 wks
C 3 wks
Thu
12-01-
17
Wed 01-
02-17 2 Thu 12-
01-17
Wed 01-
02-17 No 0 wks
D 1 wk
Thu
02-02-
17
Wed 08-
02-17 4 Thu 02-
02-17
Wed 08-
02-17 No 1 wk
E 3 wks
Thu
16-02-
17
Wed 08-
03-17 3 Thu 16-
02-17
Wed 08-
03-17 No 4 wks
F 4 wks
Thu
16-02-
17
Wed 15-
03-17 3,5 Thu 16-
02-17
Wed 15-
03-17 Yes 0 wks
G 2 wks
Thu
02-02-
17
Wed 15-
02-17 4 Thu 02-
02-17
Wed 15-
02-17 No 4 wks
H 3 wks
Thu
16-03-
17
Wed 05-
04-17 7,8 Thu 16-
03-17
Wed 05-
04-17 Yes 0 wks
I 1 wk
Thu
06-04-
17
Wed 12-
04-17 6,9 Thu 06-
04-17
Wed 12-
04-17 Yes 0 wks

The result above has been taken from the MS Project. It cannot begin earlier than first day of
the project. It will take more than 12 weeks to complete the project. A, B, H, F, and I are
critical activities Slacks are available in D (1 week), E (4 weeks), and G (4 weeks).
2.
Task Name Duration Start Finish Predecessor
s
Early
Start
Early
Finish Critical Free
Slack/Float
LaunchProjec
t 13 wks
Thu
22-12-
16
Wed
22-03-
17
Thu
22-12-
16
Wed
22-03-
17
Yes 0 wks
A 2 wks
Thu
22-12-
16
Wed 04-
01-17
Thu 22-
12-16
Wed 04-
01-17 Yes 0 wks
B 4 wks
Thu
05-01-
17
Wed 01-
02-17 2 Thu 05-
01-17
Wed 01-
02-17 Yes 0 wks
C 1 wk
Thu
05-01-
17
Wed 11-
01-17 2 Thu 05-
01-17
Wed 11-
01-17 No 0 wks
D 1 wk
Thu
12-01-
17
Wed 18-
01-17 4 Thu 12-
01-17
Wed 18-
01-17 No 2 wks
E 3 wks
Thu
02-02-
17
Wed 22-
02-17 3 Thu 02-
02-17
Wed 22-
02-17 No 3 wks
F 4 wks
Thu
02-02-
17
Wed 01-
03-17 3,5 Thu 02-
02-17
Wed 01-
03-17 Yes 0 wks
G 1 wk
Thu
12-01-
17
Wed 18-
01-17 4 Thu 12-
01-17
Wed 18-
01-17 No 6 wks
H 2 wks
Thu
02-03-
17
Wed 15-
03-17 7,8 Thu 02-
03-17
Wed 15-
03-17 Yes 0 wks
I 1 wk Thu
16-03-
Wed 22- 6,9 Thu 16- Wed 22- Yes 0 wks

17 03-17 03-17 03-17
The crashing all the activities mentioned in the table reduces the activities’ duration to13 days
in total.
3.
Task Name Duration Start Finish Predecessor
s
Early
Start
Early
Finish Critical Free
Slack/Float
LaunchProjec
t 16 wks
Thu
22-12-
16
Wed
12-04-
17
Thu
22-12-
16
Wed
12-04-
17
Yes 0 wks
A 3 wks
Thu
22-12-
16
Wed 11-
01-17
Thu 22-
12-16
Wed 11-
01-17 Yes 0 wks
B 5 wks
Thu
12-01-
17
Wed 15-
02-17 2 Thu 12-
01-17
Wed 15-
02-17 Yes 0 wks
C 1 wk
Thu
12-01-
17
Wed 18-
01-17 2 Thu 12-
01-17
Wed 18-
01-17 No 0 wks
D 1 wk
Thu
19-01-
17
Wed 25-
01-17 4 Thu 19-
01-17
Wed 25-
01-17 No 3 wks
E 3 wks
Thu
16-02-
17
Wed 08-
03-17 3 Thu 16-
02-17
Wed 08-
03-17 No 4 wks
F 4 wks
Thu
16-02-
17
Wed 15-
03-17 3,5 Thu 16-
02-17
Wed 15-
03-17 Yes 0 wks
G 2 wks
Thu
19-01-
17
Wed 01-
02-17 4 Thu 19-
01-17
Wed 01-
02-17 No 6 wks

H 3 wks
Thu
16-03-
17
Wed 05-
04-17 7,8 Thu 16-
03-17
Wed 05-
04-17 Yes 0 wks
I 1 wk
Thu
06-04-
17
Wed 12-
04-17 6,9 Thu 06-
04-17
Wed 12-
04-17 Yes 0 wks
The reduction of C considering in crash is not going to help. The decrease in the duration of
C by three days gives D and G (dependent on C) increase of slack days of two more days that
is to 3 days and 6 days respectively but does not changes the overall duration. The reason is
the starting date of tasks D and G.
4.
The method that can be applied to reduce the cost expense and also help reduce the duration
is the use of overtime. The overtime can be used by the company to reduce the costs which
comes generally cheaper than crashing the project. Adding 4 hours of overtime every day
from the day one will bring the project within 12 days target and the company does not have
to use even crashed durations.
Calculation:
Required duration = 12 weeks
Extended duration = 16 weeks
Duration to adjust = 4 weeks
Total work hours to adjust = 4weeks x 40 hours/week = 160 hours
If employees work overtime for four hours for everyday from day one, then total available
overtime hours = 12weeks x 4hours x 5days = 240 hours
Here, required is 240 hours, but needed is 160 hours. This seems more than enough. Also,
overtime is likely to cost less.