Extended Operations (ETOPS and Polar Operations)

Original publisher: [Washington, D.C.] : U.S. Dept. of Transportation, Federal Aviation Administration, [2008]. OCLC Number: (OCoLC)303643075 Subject: Airplanes -- Speed -- Certification. Excerpt: ... 6 / 13 / 08 AC 120-42B decisions successfully throughout the flight. The suitability of an en route alternate airport for an airplane that encounters an in-flight situation that necessitates a diversion during ETOPS operations is based on a determination that the airport still is suitable for the circumstances, and the weather and field conditions at that airport permit an instrument approach to be initiated and a landing completed. 207. ETOPS IN-SERVICE EXPERIENCE REQUIREMENTS. a. When AC 120-42 was first released in 1985, two-engine ETOPS was a new concept and ETOPS approvals were sought on airframe-engine combinations that were already in service. Hence, it was logical to establish criteria for approvals based on in-service experience. At that same time, the FAA recognized the possibility that other approval methods could be developed without in-service experience, and accordingly, provided statements that recognized those options. The original two-engine ETOPS requirements for engine reliability were based on a world fleet in-service experience of 250,000 hours. For 120-minute ETOPS, the FAA additionally required the certificate holder to have 12-consecutive months of operational in-service experience with the airplane-engine combination ( AEC ). For 180-minute ETOPS, the FAA required the certificate holder to have previously gained 12 consecutive months of operational in-service experience with the specified AEC conducting 120-minute ETOPS. These basic, two-engine in-service requirements have been retained and are discussed in Appendix 3. Achieving these levels of experience, combined with the required levels of engine reliability, is an acceptable means of attaining ETOPS approval for operators of two-engine airplanes. b. At the time AC 120-42A was drafted,...