The U.S. Federal Aviation Administration (FAA) issued Airworthiness Directive (AD) 2026-13-05, effective July 16, 2026, addressing an unsafe condition affecting Boeing 737-8, 737-9, and 737-8200 airplanes. The directive addresses potential BAT BUS SECT 2 and environmental control system (ECS) circuit-breaker trips that could lead to an air-conditioning system malfunction and uncontrollably high temperatures in the cabin and flight deck. The FAA determined that this condition could potentially result in injury or incapacitation of flightcrew and passengers and affect the ability to maintain safe flight and landing. AD 2026-13-05 required operators to revise the existing Airplane Flight Manual (AFM) to incorporate specified non-normal operating procedures and checklists for affected circuit-breaker scenarios. However, AD 2026-13-05 was subsequently superseded by FAA AD 2026-14-11, effective July 13, 2026, after the FAA identified a formatting error that omitted part of an appendix in the original directive. The replacement AD retained the applicable requirements and incorporated the corrected material. Operators and aviation maintenance professionals should therefore refer to the current FAA requirements under AD 2026-14-11 and the associated FAA docket for the latest compliance information.