Establishment and Maintenance of Certification Standards for Helicopter and Turboprop Power Transmission Systems,

This paper discusses how the Federal Aviation Administration FAA develops qualificationcertification safety standards for helicopter and engine turboprop drive systems. The rules are always generated in coordination with industry for a minimum of economic impact, and are worded to promote design innovation while maintaining adequate safety. The rules are periodically updated to account for service experience and advancements in the state-of-the-art. A survey of the applicable Federal Aviation Regulations FARs explains how all safety aspects of a new drive system are covered during the initial certification program. The FARs also provide for continued airworthiness, as service experience is accumulated, such that inspection intervals may be increased on on condition, or decreased, if service difficulties indicate that an area of redesign is required. As further testing continues, initial limitations on component replacement times are relaxed until operating costs decrease to a minimum as the design reaches maturity. The FAA role is to assist industry in the promotion of aviation without compromising safety.