Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, and 747-300 Series Airplanes; and Model 747SP and 747SR Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747- 200C, 747-200F, and 747-300 series airplanes; and Model 747SP and 747SR series airplanes. This AD requires revising the airplane flight manual to prohibit operation of the autopilot/flight director in command mode with performance management system selected on the speed mode switch during cruise in reduced vertical separation minimum (RVSM) airspace. This AD is prompted by reports of unexpected autopilot disconnects induced by the passing of another airplane within 1,000 feet below the airplane while they were operating in RVSM airspace. We are issuing this AD to prevent unexpected disconnect of the autopilot during operation in RVSM airspace due to close passage of another airplane, which may result in altitude deviation, and consequently, could lead to a possible mid-air collision or a near miss with aggressive evasive action (by either or both airplanes). Aggressive maneuvering at cruise altitudes and airspeeds could result in loss of control of the airplane and/or injury to passengers and crew.