Boeing 727 in Cargo Configuration - Service Difficulty Alert

AL 1999-01
7 January 1999

Passenger Cabin Window Failures

An in-flight failure of a passenger cabin outer window pane was reported on a Boeing 727 cargo airplane.

Inspection of the other cabin windows, which were all painted on this aircraft, revealed that a large number were damaged beyond the allowable limits prescribed in the Boeing 727 Maintenance Manual. A review of the SDR database revealed two similar incidents in B727 cargo airplanes; however, those SDRs did not indicate if the subject windows were painted.

Window failures which would normally be evident to passengers, flight and ground crew on a passenger configured airplane, are no longer evident on a cargo configuration when the windows are painted. The dormant failure of one window panel will impair the fail-safe design capability of the windows.

Therefore, Transport Canada strongly recommends that those cabin windows which are painted in cargo configuration be inspected in accordance with the Boeing 727 Maintenance Manual, Section 56-20-0 at every C check.

Any defects or further occurrences should be reported by sending a Service Difficulty Report to Transport Canada, Continuing Airworthiness, Ottawa.

For further information contact a Transport Canada Centre, or call Mr. Anthony Wan, Continuing Airworthiness, Ottawa, telephone (613) 952-4379, facsimile (613) 996-9178 or e-mail

For Director, National Aircraft Certification

B. Goyaniuk
Acting Chief, Continuing Airworthiness