EASA SIB NM-17-06: Boeing 737 Aeroplanes - Fuselage Skin Panels at the Chem-mill Steps

What to do

Operators of Boeing 737-200, -200C, -300, -400, and -500 series airplanes should follow the inspection procedure outlined in Boeing 737 NDT Manual Part 4, Section 53-30-12, dated November 1, 2016, as recommended by the FAA. They should coordinate with maintenance and inspection teams to implement this procedure in accordance with the existing Airworthiness Directives 2011-24-12 and 2012-26-02. No new compliance deadlines are specified in this bulletin.

Summary

The Special Airworthiness Information Bulletin SAIB: NM-17-06 is an FAA informational bulletin addressing inspection procedures for fuselage skin panels at the chem-mill steps on Boeing 737-200, -200C, -300, -400, and -500 series airplanes. It informs operators about a new inspection procedure published by Boeing to detect cracking using an improved ultrasonic phased array method. This bulletin provides guidance but does not impose mandatory requirements.

What changed

SAIB: NM-17-06 introduces a new inspection procedure documented in Boeing 737 NDT Manual Part 4, Section 53-30-12, dated November 1, 2016, as an alternative to the previously required procedure in Section 53-30-07. The FAA approved this alternative method of compliance to improve human factors when inspecting large fuselage skin areas. This update supplements existing Airworthiness Directives 2011-24-12 and 2012-26-02 by providing an enhanced inspection technique.

Why it matters

This bulletin matters because it offers operators and maintenance teams a more efficient and potentially more reliable inspection method for detecting fuselage skin cracking, which is critical for maintaining structural integrity and airworthiness. Adopting the new procedure can improve inspection accuracy and reduce human error during large-area inspections. Compliance with these inspection methods supports continued safe operation of affected Boeing 737 models.