American College of Technology
Project Scope and Scheduling
(MAPM512)
Chapter 4
Accelerate a Schedule
2
Chapter Objectives
At the end of this chapter, students shall be able to:
Develop the knowledge on applying the control philosophies
of early start and recovery
Understand how to analyze remedial action and resources to
accelerate schedules
Describe and contrast crash scheduling and fast-track
scheduling
4.1. The Basics of Schedule
Acceleration
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What is Schedule Acceleration?
Schedule Acceleration is a set of methods
used to minimize the duration of work
included into the project in order to:
Accomplish it faster than it was originally
estimated (to surpass the schedule);
Stay within the schedule if something critical
was previously delayed (overtake the schedule);
Decrease a serious project performance delay
down to an acceptable level;
Why Schedule Acceleration?
A need for project schedule acceleration may
arise when certain factors behind the schedule
have been changed, for example a customer
vitally demands a project to be completed
faster, or if work was delayed due to some
reasons, for example protractions with
supplies.
Methods to Accelerate the Schedule
Ø Canceling the staff’s days-off, vacations, weekends and adding
certain overtime work;
Ø Adding more resources (manpower and equipment) to
complete certain tasks and stages faster (“Crashing” method
of schedule compression);
Ø Performing more tasks in parallel mode, without adding
additional resources (“Fast Tracking” method of schedule
compression);
Ø Reducing the scope of work to skip or withdraw certain tasks
from the schedule;
Ø Implementing some innovative technologies and tools
increasing the productivity;
ANY QUESTION?
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4.2. Remedial actions and Resources
to accelerate Schedules
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Methods to Accelerate the Schedule
Methods Description
• The unit cost of work to be performed on a project is
calculated at the beginning of the project based on the
execution strategy of the project to meet the project
completion date.
Changing • If the project completion date is moved up, then the unit
Scope cost of work will likely increase.
• With more time, the project team may be able to schedule
activities in such a way to reduce their costs. For example,
an activity requiring overtime to be paid can now pay the
labor at normal rates, saving overtime premium.
• Available resources can be increased by adding overtime
Additional
to existing resource calendars or by hiring additional
Resources
contract workers or renting additional equipment.
• This is changing of the quality specifications of the
Changing
product.
Quality
• This is usually done as a scope change.
Five Ways to Accelerate Your Project Schedule
1. Accelerate early
2. Fast-track dependent activities
3. Remove activities that are no longer needed
4. Add resources to the critical path
5. Optimize your processes
ANY QUESTION?
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4.4 Crash Scheduling and Fast-track
Scheduling
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What is fast-tracking?
It’s a schedule compression technique when activities that
would have been performed sequentially based on the original
schedule are performed at the same time (in parallel or in
partial parallel with one another).
Careful consideration needs to be taken when changing the
activity relationships.
Although there aren’t really additional costs with this
technique, there are still risks involved.
Resequencing and rescheduling subs can be time-consuming
and potentially costly.
Further, scheduling parallel tasks can lead to excessive trade
stacking, and open the contractor up to possible disruption
claims.
Time-cost trade-offs (Crashing)
In some situations project organizations or
managers, may, want to reduce the length of
project by injecting additional resources. This may
be done:
v To avoid late penalties
v To take advantages of monetary incentives for timely
completion of a project
v To free resources for use on other projects
v To reduce the indirect costs associated with running
the project, such as facilities and equipment costs,
supervision, and labor costs.
Crashing …
However, such decisions makes the objectives of
projects (time and cost) to move in opposite
direction so as to force managers to make some kind of
trade-off decisions
In order to make a rational decision about which
activities (if any) to crash and the extent of crashing
desirable, a manager needs the following
information.
i. Regular time and crash time estimates for each activity
(how much schedule savings can be gained)
ii. Regular cost and crash cost estimates for each activity
(how much resources will be given up)
iii. A list of potential candidates (activities) for crashing
Crashing …
The general procedure for crashing is:
1. Obtain estimates of regular and crash times and
costs for each activity
2. Determine the lengths of all paths and path slack
times
3. Determine which activities are on the cortical path.
4. Crash critical activities, in order of increasing costs,
as long as crashing costs do not exceed benefits
Crashing …
Note that two or more paths may become
critical as the original critical path becomes
shorter, so that subsequent improvements will
require simultaneous shortening of two or more
path.
In some cases it will be most economical to
shorten an activity that is on two or more of the
critical paths.
This is true whenever the crashing cost for a joint
activity is less than the sum of crashing one
activity on each separate path.
Crashing …
Example:
Using the information on the next slide, develop an
optimum time-cost solution.
Assume that the crashing decision is initiated to save
indirect project costs, which is $1,000 per day.
Accordingly, the crashing will end when the direct
crashing cost exceeds the this cost savings.
.
Crashing …
Solution:
a. Determine which activates are on the critical path,
its length, and the length of the other path
Crashing …
b. Rank the critical path activities in order of lowest crashing cost
and determine the number of days each can be crashed
Crashing …
c. Begin shortening the project, one day at a time, and
check after each reduction to see which path is critical.
Thus;
Shorten activity C one day at a cost of $ 300. The length
of critical path now becomes 19 days.
Activity C cannot be shortened any more. Shorten
activity E by one day at a cost of $600. The length of path
C-D-E-F now becomes 18 days, which is the same as path
A-B-F.
• The crashing sequence is summarized below:
Crashing …
At this point it is good to consider an activity
that appears on both path as it would be
more economical to crash it.
Thus, shorten f by one day for a cost of $800.
The project duration is now 17 days.
At this point no additional improvement is
feasible. The cost to crash b is $500 and the
cost to crash e is $600 for a total of $1,100,
and that would exceed the project costs of
$1,000 per day.
Crashing …
In summary,
Total direct crashing cost =
300+600+800=$2700
Total indirect cost savings due to
crashing= number of days shortened *
indirect cost per day = 3*1000= $3000
Fast-tracking vs crashing
One common thread is that both involve
making adjustments to critical path activities.
If the schedule has been affected by severe
weather delays, fast-tracking should be the
best option.
On the other hand, if the client requests an
early delivery and is willing to pay, then
crashing may be the best method.
For instances that aren’t as clear-cut, it’s
always wise to start with fast-tracking. This is
because fast-tracking doesn’t involve any extra
resources, and it usually involves less risk.
Fast-tracking vs crashing…
If the adjustment still doesn’t get the
project back on track, then its time to
decide if crashing is necessary.
To do this, a contractor should weigh the
risk of late delivery against the cost of
crashing the schedule.
Sometimes, the harm to a company’s
reputation can be enough to outweigh
the crash-costs.
ANY QUESTION?
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Chapter 5
Managing the Schedule
(Update a schedule, prepare Progress
Report and post job review)
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Chapter Objectives
At the end of this chapter, students shall be able to:
Describe and apply the planning and control cycle
Understand how to revise schedules and resources for
actual progress and compare to baseline
Describe the concept of earned value and perform basic
earned value calculations
5.1. Describe and apply the
planning and control cycle
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Controlling Project Schedule
Controlling Schedule is the project
management activity in which progress on
project activities is compared against Schedule
baseline to understand whether project is
ahead of the schedule or behind.
Based on the deviation we can plan on
corrective or preventive actions and manage
changes to baseline.
This process helps thus reduces the risk of
delivery slippage when managed well.
Controlling Project Schedule… process
ØDetermine current status of project based on
completed deliverables against planned iteration
ØAt the end of each iteration conduct retrospective
review meetings to identify improvement areas
ØAdjust project backlog based on outcome of
retrospective review meetings
ØFind out iteration velocity (number of features
implemented per fixed duration of iteration )
ØIf all this needs schedule to change, manage the
changes and baseline it again.
Controlling Project Schedule… process
ANY QUESTION?
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5.3. Earned Value Analysis
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The Earned Value Chart…
The earned value of work performed (value
completed) for those tasks in progress is found by
multiplying the estimated percent completion for each
task by the planned cost for that task
The result is the amount that should have been spent
on the task so far
The concept of earned value combines cost reporting
and aggregate performance reporting into one
comprehensive chart
The Earned Value Chart…
Graph to evaluate cost and performance to date:
The Earned Value Chart…
Variances on the earned value chart follow two primary
guidelines:
1. A negative means there is a deviation from plan—not good
2. The cost variances are calculated as the earned value minus some other
measure
EV - Earned Value: budgeted cost of work performed
AC - actual cost of work performed
PV - Planned Value: budgeted cost of work scheduled
ST - scheduled time for work performed
AT - actual time of work performed
The Earned Value Chart…
EV - AC = cost variance (CV, overrun is negative)
EV - PV = schedule variance (SV, late is negative)
ST - AT = time variance (TV, delay is negative)
If the earned value chart shows a cost overrun or performance
underrun, the project manager must figure out what to do to
get the system back on target
Options may include borrowing resources, or holding a meeting
of project team members to suggest solutions, or notifying the
client that the project may be late or over budget
The Earned Value Chart…
Variances are also formulated as ratios rather than
differences
Cost Performance Index (CPI) = EV/AC
Schedule Performance Index (SPI) = EV/PV
Time Performance Index (TPI) = ST/AT
Use of ratios is particularly helpful when
comparing the performance of several projects
Variance Analysis Questions
What is the problem causing the variance?
What is the impact on time, cost, and
performance?
What is the impact on other efforts, if any?
What corrective action is planned or under way?
What are the expected results of the corrective
action?
Example
Planned $1500 to complete work package.
Scheduled to have been finished today.
Actual expenditure to date is $1350.
Estimate work is 2/3 complete.
What are cost and schedule variances?
Cost variance
Cost variance = EV – AC
= $1500(2/3) - $1350
= $1000 - $1350
= -$350
Schedule variance
Schedule variance = EV – PV
= $1500(2/3) - $1500
= -$500
CPI (cost performance index)
CPI = EV/AC
=($1500/(2/3) / $1350)
= 1000/1350
= 0.74
SPI (schedule performance index)
SPI = EV/PV
= ($1500(2/3))/$1500
= $1000/$1500
= 0.67
ETC and EAC
Estimate to complete = (BAC-EV)/CPI
=(1500-1000)/.74
= $676
Estimate at completion = ETC + AC
= $676 + $1350
= $2026
ANY QUESTION?
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