Airworthiness Directive · Amendment 39-15346 · Boeing Model 767-200 and 767-300 Series Airplanes
Boeing Model 767-200 and 767-300 Series Airplanes
This AD applies to Model 767-200 and 767-300 series airplanes, certificated in any category; as identified in Boeing Service Bulletin 767-21A0167, Revision 1, dated December 19, 2006; excluding variable number VK031.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 767-200 and 767-300 series airplanes. This AD requires reworking certain duct assemblies in the environmental control system (ECS). This AD results from reports of duct assemblies in the ECS with burned Boeing Material Specification (BMS) 8-39 polyurethane foam insulation. This AD also results from a report from the airplane manufacturer that airplanes were assembled with duct assemblies in the ECS wrapped with BMS 8-39 polyurethane foam insulation, a material of which the fire retardant properties deteriorate with age. We are issuing this AD to prevent a potential electrical arc from igniting the BMS 8-39 polyurethane foam insulation on the duct assemblies of the ECS, which could propagate a small fire and lead to a larger fire that might spread throughout the airplane through the ECS.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Except as provided by paragraph (g) of this AD, within 72 months after the effective date of this AD, rework the duct assemblies in the ECS for the air distribution system at sections 41, 45, and 46; the Gasper air system at sections 41, 43, 45, and 46; the forward electronic and electrical (E/E) compartment air supply; and the instrument panel cooling supply; in accordance with the Accomplishment Instructions and Appendices A and B of Boeing Service Bulletin 767-21A0167, Revision 1, dated December 19, 2006.
If an affected duct assembly having a part number other than part number 217T2109-12, or a part number other than any part number specified in the applicable figure of Boeing Service Bulletin 767-21A0167, Revision 1, dated December 19, 2006, is found installed, and that part number is listed as an optional part number in the table in paragraph 3.B.2., “Optional Part Table,” of the Accomplishment Instructions of the service bulletin: No rework is required for that duct assembly only.
As of the effective date of this AD, no person may install on any airplane an air distribution system, Gasper air system, forward E/E compartment air supply, or instrument panel cooling supply duct assembly with BMS 8-39 polyurethane foam insulation.
