WASHINGTON — The National Transportation Safety Board (NTSB) has issued a rare and “urgent” bulletin recommending safety modifications for some engines on Boeing and Airbus planes.
The safety warning was issued to address the possibility of smoke entering the cockpit or cabin of airplanes equipped with CFM International LEAP-1B engines. Additional recommendations were issued to evaluate the potential for the same issue with LEAP-1A and -1C engines.
These engines are used on variants of Airbus A320neo planes and Boeing 737 Max narrow-body passenger jets.
“The NTSB found that the engine load reduction device (LRD) a safety feature designed to reduce the severity of vibrations transmitted from a damaged engine to the airframe, can result in damage to the engine oil system. Such a condition can allow smoke from hot oil to enter the ventilation system and ultimately the cockpit or passenger cabin.”
The recommendations stem from the NTSB’s investigation into a December 2023 incident in which smoke entered the airplane after a bird flew into the left engine of a Southwest Airlines Boeing 737-8 shortly after departing New Orleans. The flight deck filled with what the crew described as “acrid white smoke” so thick that the captain had difficulty seeing the instrument panel.
The crew had to put on masks and were able to clear the smoke. The plane landed back in New Orleans and no one was injured.
A similar engine damage event occurred in March 2023 on another Southwest flight when vapor fog filled the passenger cabin after birds were ingested into the right engine shortly after departing Havana, Cuba.
“Concerned that flight crews operating these airplanes may not be fully aware of the potential hazard of an LRD smoke-related event along with the appropriate mitigation actions, the NTSB issued an urgent safety recommendation to the Federal Aviation Administration asking the agency to ensure that operators inform flight crews of airplanes equipped with the affected engines,” the NTSB wrote.
NTSB did note that Boeing has revised flight manuals for pilots detailing the steps to take to prevent smoke from entering the cockpit or cabin following an LRD activation.
The 11-page aviation investigation report is available online.
Now, the NTSB is asking the Federal Aviation Administration (FAA) to warn flight crews about the issues.
They’re also asking the FAA to require planes with affected engines to incorporate software modifications.
In a statement, Boeing told CNN: “CFM International and Boeing have been working on a software design update. We support the NTSB’s recommendation.”
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