SAIB NM-18-18

FAA Aviation Safety

SPECIAL AIRWORTHINESS

INFORMATION BULLETIN SUBJ: Equipment/Furnishings – First Observer’s Seat Cup Holder SAIB: NM-18-18 Date: July 2, 2018 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin is to advise registered owners and operators of The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, and Model 737-8 airplanes, with line numbers 1 through 6,640 inclusive, of the potential for the cup holder of the First Observer’s seat to be inadvertently removed.

At this time, the airworthiness concern is not an unsafe condition that would warrant airworthiness directive (AD) action under Title 14 of the Code of Federal Regulations (14 CFR) part 39.

Background

An operator informed us about a cup holder which stuck to a cup and was inadvertently discarded with the cup. This created an open hole, exposing the P6-11 circuit breaker panel just below the cup holder (see Figure 1). The P6-11 circuit breaker panel contains some of the airplane's primary electrical power circuit breakers. Spilling liquid or dropping something metal into the open hole could result in a short circuit of primary electrical power systems during flight.

Boeing has issued Service Bulletins 737-25-1790 (for Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes), and 737-25-1791 (for Model 737-8 airplanes). This service information provides procedures to secure the cup holder by adding adhesive film to the bottom of the cup holder flange. This improves the retention force to prevent unintended removal of the cup holder.

Recommendations

The FAA recommends that all owners and operators of the affected airplanes improve the safety of their aircraft by incorporating the instructions in the applicable service information at the earliest opportunity. The design change was incorporated in production on airplanes manufactured after line number 6,640, so those airplanes are not affected.

For Further Information Contact

Susan L. Monroe, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, AIR-785, FAA, Seattle ACO Branch, 2200 South 216th Street, Des Moines, WA 98198; phone and fax: 206- 231-3570; email: susan.l.monroe@faa.gov.

For Related Service Information Contact

The Boeing Company, P.O. Box 3707, Seattle, Washington 98124; telephone: (425) 342-6176;

fax: (425) 342-7826.

P6 PANEL

FLIGHT COMPARTMENT (LOOKING AFT)

ADD ADHESIVE FILM TO THE

BOTTOM OF THE FLANGE OF

THE FIRST OBSERVER'S SEAT

CUP HOLDER ASSEMBLY

FIRST OBSERVER'S SEAT (IN THE LOWERED POSITION © Copyright The Boeing Company; used with permission.

Figure 1 - First Observer's Seat 2