AD/B737/348 AN-26 Insulation Blankets (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Boeing 737 Series Aeroplanes

AD/B737/348 AN-26 Insulation Blankets 1/2009

Applicability:

Boeing 737-200, 737-200C, 737-300, and 737-400 series aircraft, serial numbers as defined in Boeing Special Attention Service Bulletin 737-25-1572.

Requirement:

1.    Either:

a.     Remove all insulation blankets from the pressurized areas of the fuselage and install new insulation blankets using a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA.  The new insulation blankets must comply with 14 Code of Federal Regulations (CFR) 25.856(a).  The areas where the affected insulation blankets are installed include, but are not limited to, the following areas:

(i)      Crown area of the airplane;

(ii)      Areas behind flight deck panels and circuit breaker panels;

(iii)     Areas behind sidewalls, lavatories, closets, and galleys;

(iv)     Cargo compartment areas;

(v)     Air ducting;

(vi)     Waste and water tubing; and

(vii)    Areas attached to the underside of floor panels. ; or

b.    Remove the existing fuselage insulation blankets and install new insulation blankets, in accordance with the Accomplishment Instructions of the Boeing Special Attention Service Bulletin 737-25-1572.

However, these actions are not required for any insulation blanket that is determined not to be constructed of Orcon Orcofilm AN-26, using an identification method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA or in accordance with Appendix A of Boeing Special Attention Service Bulletin 737-25-1572.

2.    No person may install any insulation blanket constructed of AN-26 as a replacement unless it has been modified to comply with 14 CFR 25.856(a).

Note 1:  Insulation material that is part-marked with a date of manufacture indicating that it was manufactured before July 1981 or after December 1988 is not constructed of AN-26.

Note 2:  FAA AD 2008-23-09 refers.

Compliance:

1.    Within 96 months after the effective date of this Airworthiness Directive.

2.    After the effective date of this Airworthiness Directive.

This Airworthiness Directive becomes effective on 15 January 2009.

Background:

This Airworthiness Directive results from reports of in-flight and ground fires on certain airplanes manufactured with insulation blankets covered with a specific polyethyleneteraphthalate (PET), ORCON Orcofilm AN-26 (all variants, including AN-26, AN-26A, and AN-26B), which may contribute to the spread of a fire when ignition occurs from sources such as electrical arcing.  We are issuing this Airworthiness Directive to ensure that insulation blankets constructed of AN-26 are removed from the fuselage.  Such insulation blankets could ignite and propagate a fire that is the result of electrical arcing or sparking.

David Villiers
Delegate of the Civil Aviation Safety Authority

24 November 2008