Delta Air Lines

DAL Flight Operations agrees and understands the importance of mitigating Engine Flameout due to encountering ice crystals. However in reference to the recent Supplemental NPRM FAA-2008-0402, DAL provides the following comments. In referencing Boeing’s original FCOMB DAL 4-17 titled "Engine Flameout Protection GE CF6-80C2 Engines" along with subsequent communication; it is DAL understanding that the risk of flameout due to ice crystals occurs only when the aircraft is near convective weather systems. Since our flight crews can recognize nearby convective weather, DAL requests the qualifier (or prerequisite) “when near convective weather systems, including thunderstorms” is added to the compliance statement. This would prevent the unnecessary increase in fuel burn and overuse of Engine Anti-Ice when engine flameouts due to ice crystals are not a factor. DAL suggests the statement can be reworded as follows: “Prior to descent in visible moisture with TAT less than 10°C, including SAT less than -40°C when near convective weather systems, including thunderstorms, nacelle anti-ice switch must be in the ON position. At or below 22,000 ft, wing anti-ice selector must be in the ON position.''