reliability engineering

Originally presented at IMC-2006 - The 21st International Maintenance Conference

In an airline environment, there is only one acceptable standard - perfection.

Safety is everything, and since reliability is a large factor in safety, it gets a lot of attention.

An airline looks at reliability at every level of the operation, from performance of an aircraft to performance of the individual piece-parts of that aircraft. Airlines look at the impact of everything that touches an aircraft. Everything is calculated and recalculated to determine the impact to the operation. Small changes can impact the operation in a large way, and those impacts have to be predicted and dealt with.

During my 27 years with DuPont, the safety culture was apparent. It was a part of everyone's job every day. As a result of a benchmarking study in the late 1980's and creation of a System Dynamics model to explain the benchmark results, it became clear that safety and reliability operate on the same principles. Both are significantly affected by defects and both require a commitment from everyone in the organization for improvements to be achieved.

Creating a structured reliability engineering department in a facility that has never had one is challenging enough. If you simultaneously implement a new computerized maintenance management software (CMMS) program, the hurdles get higher. The key to success is to have the right management support, good communication and a clear vision of what the future should be. This paper will discuss some of the triumphs and pitfalls that we have encountered on our unending journey through a complex culture change.

Risk management in military aviation has been a formal discipline in the field since the 1960's. The risk standards issued by the Department of Defense in 1969 was entitled "DoD Standard Practice for System Safety", MIL-STD-882. Air Force wide, the examples set forth in this standard have been used as though they were a required set of probabilities rather than examples. The semi-quantitative approach used today is further devalued by manager's arbitrary use of the Hazard Risk Matrix levels to mandate action. This paper examines the alternatives available today and recommends incorporation of a quantitative approach for more fidelity in risk management at all levels of management.

Editors Note: Although this paper is aimed at military aviation, the information on risk assessment and management is applicable to most industries as well.

Sterling Steel produces 450,000 tons of wire rod for its parent company, Leggett & Platt. The long products mini mill utilizes a 415 ton Electric Arc Furnace; two Ladle Metallurgy Facilities; an eight strand Billet Caster and a single strand Rod Mill to produce the wire rod for Leggett & Platt's Wire Mills.