The Federal Aviation Administration (FAA) has issued a new airworthiness directive for certain models of Boeing 737 after it received reports that the emergency escape slide had been known to accidentally and unexpectedly inflate inside the passenger cabin.
Airlines were first made aware of the danger in August 2021 after Boeing sent out a ‘Special Attention’ bulletin to affected operators, including American Airlines, Southwest Airlines and Singapore Airlines, although the directive won’t officially come into force until June 29, 2023.
The FAA described the problem as “uncommanded escape slide deployments in the passenger compartment”, which were “caused by too much tension in the inflation cable and the movement of the escape slide assembly in the escape slide compartment”.
Affected aircraft operators will be required to inspect all escape slide assemblies to identify if it has an affected part and, if identified, replace the entire assembly at a cost of $19,000 per slide.
The slides are door mounted inside the cabin and, in the event of an evacuation, are designed to drop outside and attach to the seal of the doorway. If deployed inside the passenger cabin, the slides have the potential to cause serious injury and damage.
The FAA said it had taken the decision to issue the airworthiness directive to “address the unsafe condition on these products.”
“The FAA is issuing this AD to address inflation of the escape slide while it is in the escape slide compartment, which could result in injury to passengers and crew during normal operation, or impede an emergency evacuation by rendering the exit unusable,” the agency said on Thursday.
As many as 2,502 aircraft registered in the U.S. alone will need to be inspected, although it’s not known how many will require additional work to render them safe.
