EASA SIB 2007-31
FAA SAIB NM-07-55 - Gulfstream GV series aircraft - Loss of Normal Cabin Pressurization Control due to a Pack Inlet Valve Failure
Summary
FAA Special Airworthiness Information Bulletin NM-07-55 is an informational bulletin addressing a loss of normal cabin pressurization control in Gulfstream GV series aircraft, specifically serial numbers 501 through 686 and 699, equipped with pack inlet valves part numbers 396610-1 or 396610-2. The bulletin reports incidents where pack inlet valve failures caused abnormal cabin altitude increases during descent. This document is supported by EASA Safety Information Notice 2007-31, which informs European operators of the same issue.
What Changed
This bulletin introduces awareness of a potential failure mode in the Environmental Control System pack inlet valves on affected Gulfstream GV aircraft that can lead to loss of normal cabin pressurization control. It recommends inspection of the pack inlet valves as detailed in Gulfstream GV Customer Bulletin 84 but does not mandate any regulatory action or Airworthiness Directive at this time.
Why It Matters
The loss of cabin pressurization control poses a safety risk during flight, potentially leading to rapid cabin altitude increases and crew alerts. Operators, maintenance organizations, and compliance teams need to be aware of this issue to prevent in-flight pressurization anomalies and ensure continued airworthiness. Early detection and corrective action can mitigate operational disruptions and enhance passenger safety.
What To Do
Operators of Gulfstream GV series aircraft with the specified pack inlet valves should perform a one-time inspection of the left and right pack inlet valves following the procedures outlined in Gulfstream GV Customer Bulletin 84. While no mandatory compliance deadline is set, it is strongly recommended to complete the inspection promptly to identify and address any valve malfunctions.
AI-generated summary from official EASA source document. Always verify against the original.