Introduction to Work Breakdown Structures

Work Breakdown Structures is a key project deliverable and defines the scope of work required to complete a project. WBS  is defined by the project team and it may vary from project to project depending on its requirements and complexity.

Aerospace and Defense manufacturing is a complex domain, though it involves a lot of tasks and activities, they are not like each other. Hence, using information and resources becomes a challenge without a WBS in place.

What is a Work Breakdown Structure WBS?

Work Breakdown Structure breaks down the large chunk of tasks into smaller parts which are then taken up by respective department and management groups, and each one of them needs to complete the task within the boundaries set by the amount of resources available, budget, man-power etc. as agreed with the project team. A very important definition with respect to a WBS is a deliverable, which is a unique product or capability that is required to fulfill a particular task. On the other hand, a work package is a deliverable which is at the bottom of the work breakdown structure. Consider, the construction of a commercial purpose building. In such an instance, the work package will be the roofing activity. In simple words, a work breakdown is an outline for the project and it defines the boundaries of it.

Why is there a need for a Work Breakdown Structure?

If a work breakdown structure is established in place, it is not only beneficial for the specific project and enables it to be completed successfully, it can bring benefits to the organization as well. The advantages include:

  • It helps identify the most important details of the project including the budget and risks at all points of completion.
  • Provides a deeper outlook to the project beyond the top-level requirement which helps in scheduling it effectively among different teams.
  • Helps build team communication so that every member is in sync with the other during the course of the project.
  • Aids in tracking the progress easily. If it is falling behind in deadlines, one can look at the work breakdown structure to identify the work package that is causing the delay.
  • Facilitates the assignment of tasks to team members, which helps the members to recognize their accountability for their work.

Work Breakdown Structure for Aerospace and Defense Manufacturing

It is important in Aerospace Manufacturing to have a detailed and robust WBS because it involves the development of many small and big parts and then all of them are usually assembled at one unit. Also, it is usually the different vendors who develop different parts. Thus, there is a need for effective communication to be established between the project team so that the work is in sync at all times.

aerospace defense wbs

The image provided above is a sample WBS for manufacturing an aircraft. The WBS process involves defining the major deliverables and their work packages which are Project Management, Employee Training, Data Management, Aircraft Equipment, Support Equipment, Facilities Management, and Test Evaluations. Each major deliverable can (and often does) have multiple distinct activities or work packages which can be broken down even further with more complex projects. The major deliverable cannot be completed until all of the supporting work packages have been completed.

The example above is of course overly simplified. The WBS for an aircraft assembly is exceedingly more complicated and could have hundreds of deliverables and thousands of work packages. WBS is not just a requirement for manufacturing very large equipment like aircraft or tanks. WBS is prolific throughout the A&D industry including downstream suppliers of most components utilized in the final products.

Work Breakdown Structure Modifications in A&D

Note that the WBS structure is not static, it is extremely important to note that all elements of the WBS may be different based on variables such as the type of equipment or even the model or year of the manufacturing. There are multiple reasons for this but WBS ensures that everything is completed on time, all parts and systems are compatible and tested, and that employees have been properly trained, and all other factors have been addressed before the completion of the project.

It is also important to understand that there can be multiple companies, departments, and employees working on various aspects of the WBS at the same time and each will have their own nuances and details for their assigned deliverable or work package.

Companies often start with a WBS template that includes similar deliverables and work packages common for the products they make. They then tailor the template WBS based on the specific project they’re working on.


WBS defines the scope of the aerospace and defense projects and serves as the backbone for the completion of them. The defense projects which again involve a lot of complexity, makes it extremely hard to obtain a holistic view of the project and to reuse the existing information. The nature of WBS is also dynamic and is made to be evolved to meet the changing demands of the project.

Infor CloudSuite Industrial

Infor CloudSuite Industrial ERP products offer a robust and comprehensive set of business applications supporting much of the WBS process with critical information on items, vendors, item details, serial and lot information, reporting, and more. Further, some aspects of the WBS can be managed directly inside Infor CSI which provides in-the-box project management features. Integration to leading third party WBS applications is common for larger companies.

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