Systems Engineering: Work Breakdown Structures

MN 3221 Principles of Systems Acquisition and Program Management Systems Engineering: Work Breakdown Structures

John T. Dillard [email protected] 831.656.2650

GRADUATE SCHOOL OF BUSINESS & PUBLIC POLICY U.S. NAVAL POSTGRADUATE SCHOOL

This module is all about the Work Breakdown Structures.

1 Work Breakdown Structure

• A Tool to allow PMs and Contractors to break large tasks into smaller, understandable sub-tasks • Developed through the Systems Engineering Process (SEP) • WBS relates the elements of work to be accomplished to each other and the End Product • Can be expressed down to any level of interest – PMs usually develop the Top Three WBS Levels – More levels may be developed for Higher Risk Programs

In this lesson we look at one of the most useful tools that Project Managers across any industry have – the Work Breakdown Structure, or WBS. Nobel Laureate Herb Simon noticed hierarchy in all things natural and artificial, and here is a perfect example of how we not only observe its existence, but use systems hierarchy in a variety of ways. It’s the only way we’ve yet devised to manage the complexity of large systems.

2 Work Breakdown Structure Guidance

Defense Acquisition Guidebook

• The WBS relates the elements • Contract WBS provides a of work to each other and to the framework for ….. end product. • The program WBS is a hierarchy – Program Planning of product-oriented elements – Technical Planning – Hardware – Cost Estimating –Software – Resource Allocation – Services – Performance Measurement –Data – Facilities – Status Reporting • The program WBS is extended – Technical Assessment to a contract WBS that defines • In particular, the contract WBS the logical relationship between the elements of the program provides the reporting structure and corresponding elements of used in contract management the contract work statement. reports Requires MIL-HDBK-881 be Cited

“For Guidance Only” …… 3 the Acquisition Guidebook advises that MIL Handbook 881 is a MILSPEC that can be cited “for Guidance only” in our contracts with industry. And quoted from it are these comments here about the many uses of the WBS.

3 Basic Purposes of WBS

• Organizational: – Road Map for concurrent management of the program – Provides structure for assigning multi-disciplinary IPT’s •Technical: – Tool to design and then track technical work – Relates to SOW and CLIN development – A tool for Risk Assessment – Provides for establishing interface identification and control – Provides product items by group for specification development – A tool for managing engineering change proposals – Provides a structure for reviews and audits •Business: – Provides structure for Budgets and cost estimates – Provides a structure to collect and analyze costs for CPR or EV reporting

It truly provides these three important frameworks: Organization, Technical and Business.

43 Work Breakdown Structure (MIL-HDBK- 881) • Provides Instructions on how to Prepare, Understand and Construct a Program WBS • Provides Guidance for Preparing a Contract WBS on – the Role of WBS in Negotiation and Award – the WBS Function in Measuring Post-Contract Performance • Designed to Provide a Consistent Application of WBS across DoD – Contains many Sample Formats for WBS development

MIL HANDBOOK 881 is the true source for knowledge about WBSs – -- a direct result of the SEP process and all that functional decomposition and Synthesis we looked at earlier.

5 Program WBS

• Consists of at least the Top Three WBS Levels • Encompasses the Objectives of the Entire Program • Developed and Maintained by the PM • Used to develop the Contract WBS

A “program” WBS is typically the top 3 levels of the WBS. It’s usually about all the level of detail we have at the beginning of a program.

6 WBS Development

Aircraft System Level 1 is the “Defense Materiel Item” and refers to All elements required to Acquire, Employ & Support the system over its intended Life Cycle

1.0 Air Vehicle 2.0 Data 3.0 Training 4.0 Facilities Level 2 breaks out the “Major Elements” of the Defense Materiel Item

1.1 Air Frame 1.2 Propulsion 1.3 Flight Software 1.n Level 3 identifies Major “Subordinate Elements” of each Level 2 Major Element 7

Shown here is an airplane example. Note the kinds of things going on at the second level, versus the things at the third level. We often call Level 2 the “producing” part versus the “product” part of the WBS. It lists the activities associated with developing, testing, and producing, etc. the system.

7 Aircraft Systems Work Breakdown Structure Level 1 Aircraft System Level 2

Air Vehicle Sys Eng/ System Training Data Peculiar Common Opn'l/Site Industrial Initial Program T&E Support Support Activation Facilities Spares Mgmt Equipment Equipment & Initial Repair Airframe DT&E Equipment Tech Test & Test & Sys Assembly,Construction/ Parts Conversion/ Propulsion Pubs Measurement Measurement Installation & OT&E Services Equipment Equipment Checkout on Expansion (Specify by Application Software Eng Allowance Data Support & Support & Site System Software Mockups Facilities Equipment List, Support Handling Handling Contractor Acquisition Grouping, Comm's/Identification T&E Data Equipment Equipment Tech Support or Mod or H/W Support Element) Navigation/Guidance Management Site Central Computer Construction Maintenance Test Data Fire Control Facilities Data Site/Ship Repository Vehicle Data Display & Controls Conversion Survivability Reconnaissance Automatic Flight Control Level 3 Central Integrated Reference: Checkout Antisubmarine Warfare MIL-HDBK 881 Armament Weapons Delivery Auxiliary Equipment

From MIL-Handbook 881A – a further refined WBS showing all 3 levels in more detail.

8 Contract WBS

• Includes Program WBS elements that are the Contractor’s responsibility • Used to Organize and Identify Contractor tasks • Contract WBS is developed at least to the lowest level contractually required for status reporting • High Risk or High Cost or very Complex elements may require more WBS levels of detail • Forms the Structure for the Contractor’s Management Control System (usually Earned Value)

A Contract WBS elaborates on the Program WBS, and takes it to 4th, 5th 6th levels and beyond if necessary. It’s usually proposed back to the government from industry for a contract to be awarded.

9 Work Breakdown Structure

WBS Lvl 1 AIRCRAFT SYSTEM PRODUCT

WBS Lvl 2 TEST AIR SUPPORT VEHICLE

FIRE WBS Lvl 3 (1) CONTROL

WBS Lvl 4 (2) TEST RADAR SUPPORT

RECEIVER ANTENNA TRANSMITTER WBS Lvl 5 (3) GROUP GROUP

WBS Lvl 6 (4) UNIT 1 UNIT 2 UNIT 3

The size of this hierarchical “project tree” can really grow as we go further and further down. We get all the way down to micro circuitry and fasteners if need be.

10 The Control Account

• Lowest level of the WBS from a PM’s perspective – Control account may include work packages (Engr perspective) • WBS level at which management control is established – Specific Functional responsibility – Specific WBS responsibility – Work planning and assignment – Baseline (BCWS) – Performance Measurement – Earned (BCWP) – Collect Costs (ACWP) – Analyze Variance in cost or schedule – Basis for WBS Summarization

The more detail the better, as we use WBS for the cost accounting of the project. After all, it represents the “scope of work” – everything that needs to be done on the project. At the lowest level, we establish (cost) “control accounts” to track the time and materials needed for each work package or several collective work packages of effort.

1122 The Control Account

An interesting visual correlation is an organization turned on its side, aligned with the cross-functional work that must get done. We will typically take control accounts down to a 40-hour man-week of labor. That’s about as detailed as we’ll get on a big system like an aircraft or submarine.

12 WBS and the 5000 Framework

Concept Refinement

Technology Development

Progressive elaboration of the WBS proceeds as we go through time and acquisition phases.

13 WBS and the 5000 Framework

Engineering & Manufacturing Development (formerly called SDD)

And when we commence SDD/EMD, we should be able to specify to our teammates in industry what our system looks like to the top three levels of specificity.

14 WBS Summary

• WBS Provides a Product-Oriented definition of the Entire System to any desired level of detail • MIL-HDBK-881 must be cited ‘For Guidance Only’ – Contains guidance for WBS development – Contains Sample WBS formats for many types of development •Two types of WBS – Program WBS – at least the Top Three WBS Levels – Contract WBS – Requires sufficient detail to accomplish contractual reporting requirements

So in summary, the WBS is this product-oriented hierarchical “tree” that defines the entire system down to the circuit card level – or even below. It thereby gives us our business, technical, and organizational frameworks for advanced development. And it progresses in detail over time.