AD FAA-2020-0684

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-300, -400, -500, -600, -700, -700C, -800, -900, and -900ER series airplanes. An emergency AD was sent to all known U.S. owners and operators of these airplanes. This AD requires inspections of the engine bleed air 5th stage check valve on each engine, and replacement of the engine bleed air 5th stage check valve if any inspection is not passed. This AD was prompted by four recent reports of single-engine shutdowns due to engine bleed air 5th stage check valves being stuck open. The FAA is issuing this AD to address the unsafe condition on these products.