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acceleration of the design process is uneven.
The Way Forward: New Technology
Above we listed 8 factors that contribute to project failure. We will now show how a different
approach to planning can resolve some of these issues and improve project performance. To run
projects efficiently it is necessary to put accurate values into the design iteration cycle and to
understand dependencies. We contend that tools are required that can adequately model the full
complexity of the iterative design cycle on large projects, as well as representing the work breakdown
structure in a clear and user-friendly fashion. A joint project to find this kind of tool and an
accompanying project methodology has been underway for some years at the Universities of
Southampton and the West of England.
As we have argued above the existing major project planning tools, such as critical path method
(CPM) and programme evaluation review technique (PERT), use an underlying logic that was
originally developed over 50 years ago. It is clear that large, complex projects exceed the capabilities
of current project management tools and the representation on which they are based. There is a clear
need for a new approach. Our research shows the need for a new kind of project planner with a
sophisticated symbology for project representation and a methodology designed to address the causes
of project failure.
The Need to Model Iterations
In most engineering projects iterative activities can be construed as a feedback “loop”. Within this
loop interdependencies exist and there is no explicit order or sequence for the relevant activities. For
this reason existing planning tools cannot permit such constructs and they are treated as errors in the
network that need to be removed. This is highly problematic in engineering as improving project
performance requires accurate sequencing of design dependencies.23 To show an example of the
problem an extract from a complex network of information flows and dependencies for an aerospace
project is given in figure 2 above.
An illustration of a single activity loop is shown in figure 3 below. This shows that the key tasks in
designing an aerospace product such as an aircraft wing have circular dependencies forming a loop.
This apparent logical conundrum is solved by breaking the dependencies and getting one of the
activities to define an initial estimated output. By iterating round the loop a number of times this
initial estimate can be refined to an acceptable level of accuracy.
23 J.U. Mahaswari and K Varghese ‘A Structured Approach to Form a Dependency Structure Matrix for
Construction Projects’ ISAAR, Ferrara, Italy, (September 2005).
Why Projects Fail
11
Figure 3 Basic Aircraft Wing Design Iteration
To model this using existing tools requires the planner to make a guess as to the number of iterations
required for this loop. Assuming that, say, three iterations are judged to be necessary, then this would
be have to be modelled explicitly in a non-cyclic dependency network as shown in figure 4.
Figure 4 Iterations Modelled Using Existing Planning Tools
As can be clearly seen the non-cyclic dependencies for even a basic task look very complex.
Therefore, the inability to model iterations correctly is not only inaccurate; it adds unnecessary levels
of complexity into the plan. In order to conduct design activity in a more efficient manner a tool and
planning process is required than can offer the following:
 It must not be reliant on the judgement of a project manager to determine how many iterations
are required within iterative loops;
 It must give a very efficient and compact network representation;
 In order to connect with established practice it must offer compact Gantt chart representation,
which can show multiple iterations on the same activity line;
 The Planner must automatically work out how many iterations are required to best meet
project objectives;.
 It must be able to cope with a complex network containing a large number of intersecting
iterative loops typical of real project dependencies.
Determine
aerodynamic
shape
Span, Chord,
Section
Calculate
structural loads
Load cases
Design Load
bearing
structure
Wing box design,
Material volume, density
Calculate
structural mass
Mass of wing structure,
Systems, fuel
Determine
aerodynamic
shape#1
Span, Chord,
Section
Calculate structural
loads#1 Load cases
Design Load bearing
Wing box design, structure#1
Material volume, density
Calculate
structural mass
#1
　
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