EASA SIB NM-18-18
Boeing 737 Aeroplanes - Equipment/Furnishings — First Observer—s Seat Cup Holder
Summary
The FAA Special Airworthiness Information Bulletin SAIB: NM-18-18 addresses a potential issue with the First Observer's seat cup holder on Boeing 737-600, -700, -700C, -800, -900, -900ER series airplanes, and Boeing 737-8 airplanes with line numbers 1 through 6,640. The bulletin informs operators about the risk of the cup holder being inadvertently removed, which could expose the P6-11 circuit breaker panel and potentially cause electrical short circuits. This information bulletin is advisory and does not mandate regulatory action.
What Changed
SAIB NM-18-18 introduces awareness of the cup holder retention issue and Boeing's service bulletins 737-25-1790 and 737-25-1791, which provide procedures to secure the cup holder by adding adhesive film to its flange. The bulletin clarifies that airplanes manufactured after line number 6,640 already incorporate this design change in production.
Why It Matters
This bulletin is important for aviation professionals because the inadvertent removal of the cup holder could expose critical electrical circuit breakers, risking electrical system failures during flight. Operators and maintenance teams need to be aware of this potential safety concern to prevent possible short circuits caused by spilled liquids or foreign objects entering the exposed panel.
What To Do
Owners and operators of affected Boeing 737 models are recommended to apply the procedures outlined in Boeing Service Bulletins 737-25-1790 or 737-25-1791 to secure the cup holder at the earliest opportunity. Airplanes produced after line number 6,640 are not affected and do not require action. No mandatory compliance deadline is specified.