Based on a recent report of a burnt
insulation blanket, the Federal Aviation Administration
(FAA) has ordered operators of 45 U.S.-registered MD-11s
to verify the installation of a wire harness support
bracket and clamp in the lower center cargo compartment.
A missing bracket and clamp could cause a wire bundle to
contact the insulation blanket and rub against the
fuselage frame, producing a possible fire source.
This Emergency Airworthiness Directive (AD) does not
appear to be related to the Swissair accident. However,
it is prompted by information from the agency's
continuous post-accident review of the service experience
of the MD-11 fleet. While performing routine maintenance
on an MD-11, mechanics found evidence of wire chafing in
the cargo loader control unit and burnt insulation. They
also discovered that a wiring harness support bracket and
clamp that supports a wire bundle may not have been
installed on the aircraft.
This AD affects MD-11s equipped with a 72-inch cargo
door. MD-11s with a 104-inch cargo door have a different
wire bundle configuration. Operators of the affected
aircraft are required to perform inspections, verify the
installation of the bracket and clamp, and repair any
damaged wires within five days. All findings must be
reported to the FAA within 10 days after completion of
There are 45 U.S.-registered aircraft, both passenger and
cargo, affected by this AD out of a total of 89 aircraft
worldwide. Operators include American Airlines, Delta Air
Lines, World Airways, Federal Express Corporation, and
The Boeing Company. The total estimated cost to inspect
the U.S. fleet is $8,100, $180 per aircraft.