EASA SIB SAFO13006
Boeing 737-100/-500 Aeroplanes - Flight Deck Overhead Wiring-Ducting Chaffing, Arcing, and Burning Damage
Summary
The Safety Alert for Operators SAFO 13006 addresses chaffing, arcing, and burning damage risks associated with the flight deck overhead wiring-ducting on Boeing 737-100 through 737-500 series aircraft. It highlights a hazardous condition caused by improper installation of the metallic gasper air duct hose thumb clamp, which has led to serious electrical damage and fire incidents. The document provides background, discusses contributing factors, and references Boeing Service Bulletin 737-21-1186 for inspection and corrective actions.
What Changed
SAFO 13006 introduces awareness of a specific wiring hazard related to the gasper air duct clamp orientation on Boeing 737-100/-500 series aircraft. It recommends inspection of the clamp orientation and part number, and offers replacement of the metal clamp with a plastic tie strap as per Boeing Service Bulletin 737-21-1186. The SAFO also calls for updates to maintenance manuals to include clearer installation instructions and warnings.
Why It Matters
This SAFO is critical for aviation professionals because improper clamp installation can cause severe electrical damage, fires, and flight disruptions. Maintenance personnel and operators must understand the risk to prevent potential in-flight or ground safety incidents. Compliance ensures continued airworthiness and reduces the likelihood of costly repairs and safety hazards.
What To Do
Operators of Boeing 737-100 through 737-500 series aircraft should immediately alert maintenance teams about the clamp installation issue and incorporate Boeing Service Bulletin 737-21-1186 at the next maintenance opportunity to inspect and replace clamps as needed. Additionally, operators should develop supplements to maintenance manuals to ensure proper installation guidance is followed. Feedback on the effectiveness of Electrical Wiring Interconnection Systems tasks is requested by the FAA.