AC 120-42B ETOPS and Polar Ops - Code7700

AC 120-42B 6/13/08(2) Any additional restrictions imposed or, alternatively, any deviations granted tooperate in excess of the basic requirements, were based on a finding by the Administrator thatadequate safety would be provided in the proposed operation and current levels of safety wouldbe maintained when all factors were considered. This finding was never limited to enginereliability alone.(3) The airports used in meeting the provisions of the rule must be adequate for theairplane used (that is, available for safe landings and takeoff with the weights authorized).(4) Adequate levels of safety within the operation are to be maintained. Operations overincreasingly remote areas and the possibility of increased diversion lengths have a potentiallynegative impact on the safety of the diversion, and thus the operation as a whole. Additionalregulatory requirements are intended to ensure that this potential increase in risk is mitigated andthat adequate levels of safety within operations are retained.(5) When considering the impact of operating at greater distances from airports, thecertificate holder must show that the operation can be conducted at a level of reliability thatmaintains an acceptable level of risk.b. In June of 1985, responding to the industry’s desire to take advantage of the increasedreliability and capabilities of two-engine airplanes, the FAA issued AC 120-42. This ACprovided guidance on one means of obtaining deviation authority from § 121.161 to allowtwo-engine airplanes to operate on routes up to 120 minutes from an adequate airport afterdemonstration of specific levels of in-service experience and systems reliability. The FAAamended this AC in 1988 (AC 120-42A) to permit two-engine airplanes to operate up to180 minutes from an adequate airport. These ACs introduced the term “ETOPS” for thosespecific Extended Operations and addressed airplane and engine design aspects, maintenanceprograms, and operations. Both of these ACs encompassed the following precepts:(1) Reliance on a two-step approval that included type design of the airplane-enginecombination and approval of the certificate holder’s operation.(2) Risk, as measured by diversion length, is mitigated by application of regulationsand guidance reflecting current best practices that address the type certification of the ETOPSairplane and its systems as well as the operational environment of such operations.(3) ETOPS can be managed successfully, and the level of safety can be maintained, byup-to-date regulations and guidance that articulate quantifiable standards of reliability andexperience.c. The original guidance for extended-range operations with two-engine airplanes inAC 120-42 allowed an increase of up to 15 percent to the maximum diversion time of120 minutes. This provision was eliminated with the release of the guidance in AC 120-42A,providing for operations up to 180 minutes. Recognizing a need for ETOPS diversion authoritybetween 120 and 180 minutes, the FAA reinstated the 138-minute provision by issuing EPL 95-1in 1994. In March of 2000, at the request of the industry, the FAA issued ETOPS Policy Letter(EPL) 20-1, 207 Minute ETOPS Operation Approval Criteria. This document provided a similarPage 4 Par 201