Action
Final rule; request for comments.
Summary
We are superseding an existing airworthiness directive (AD) for the products listed above. That AD currently requires you to incorporate operating limitations of maximum operating altitude of 37,000 feet into Section 2, Limitations, of the airplane flight manual (AFM). This AD requires you to incorporate operating limitations of maximum operating altitude of 30,000 feet into Section 2, Limitations, of the AFM. This AD was prompted by several incidents of engine surge. We are issuing this AD to prevent hard carbon buildup on the static vane, which could result in engine surges. Engine surges may result in a necessary reduction in thrust and decreased power for the affected engine. In some cases, this could result in flight and landing under single-engine conditions. It is also possible this could affect both engines at the same time, requiring dual-engine shutdown.