A B777-200 diverted to a nearby airport when the cargo detectors for the aft cargo compartment faile...

Attributes
ACN	896635
Time
Date	201006
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Cargo Compartment Fire/Overheat Warning
Person 1
Function	Check Pilot Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 146 Flight Crew Total 13500 Flight Crew Type 3279
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

Narrative:

At cruise alt of FL370 a status message appeared. We looked up the info for the det zone 1 cargo aft message. This was one of three messages. Zones 1; 2; 3 showed the same message. We concluded that the aft cargo area has one smoke detector and three sensors. If the three sensors were faulted; that left the aft cargo without detection. We contacted dispatch and maintenance control. The decision was made to divert to ZZZ due to the lack of fire detection in the aft cargo area. We then dumped over 44;000 pounds of fuel coordinated with ATC. We landed uneventfully. Maintenance ran some tests and reset the system. The aircraft had a history of this issue. No parts were available in ZZZ. The cargo was removed and the detectors deferred. We then continued on to our destination. The 3 det messages came back on an hour past our coast out point. We again advised dispatch and decided to continue on to our destination.

Original NASA ASRS Text

Title: A B777-200 diverted to a nearby airport when the cargo detectors for the aft cargo compartment failed.

Narrative: At cruise alt of FL370 a status message appeared. We looked up the info for the DET ZONE 1 CARGO AFT message. This was one of three messages. Zones 1; 2; 3 showed the same message. We concluded that the aft cargo area has one smoke detector and three sensors. If the three sensors were faulted; that left the aft cargo without detection. We contacted Dispatch and Maintenance Control. The decision was made to divert to ZZZ due to the lack of fire detection in the aft cargo area. We then dumped over 44;000 pounds of fuel coordinated with ATC. We landed uneventfully. Maintenance ran some tests and reset the system. The aircraft had a history of this issue. No parts were available in ZZZ. The cargo was removed and the detectors deferred. We then continued on to our destination. The 3 DET messages came back on an hour past our coast out point. We again advised Dispatch and decided to continue on to our destination.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.