Aviation safety issues and actions

Floor sealing design

Issue number: AO-2008-003-SI-02
Who it affects: Operators of Boeing 747-400 aircraft
Issue owner: Boeing Co
Transport function: Aviation: Other
Background: Investigation Report AO-2008-003
Issue release date: 13 December 2010
Current issue status: Partially addressed
Issue status justification:

The ATSB is satisfied that, when completed, the actions being undertaken will adequately address the safety issue.

Safety issue description

The location of the decompression panel and absence of cabin floor sealing above the main equipment centre increased the risk of liquid ingress into the aircraft’s electrical systems.

Proactive Action

Action number: AO-2008-003-NSA-029
Action organisation: Boeing Co
Date: 13 December 2010
Action status: Closed

In response to this occurrence, the aircraft manufacturer:

  • issued a multi-operator message containing a recommendation that operators review decompression panels that have been relocated after delivery to verify that they do not become a direct water path to the main equipment centre dripshield
  • is investigating a number of methods to improve floor sealing in 747-400 aircraft.

ATSB comment:

The ATSB is satisfied that, when completed, the actions taken or that are being undertaken by the aircraft manufacturer will adequately address the safety issue.

Proactive Action

Action number: AO-2008-003-NSA-030
Action organisation: Qantas Airways
Date: 13 December 2010
Action status: Closed

The aircraft operator has advised that, in response to this occurrence, it has:

  • installed a water barrier gutter at the rear of the forward galley bulkhead on all of its 747-400 fleet
  • installed an additional bead of sealant around the first-class seat pods to protect the decompression panel on all of its 747-400 fleet.

ATSB comment:

The ATSB is satisfied that the actions taken by the aircraft operator adequately address the safety issue.

Last update 07 March 2014