Winston
7th Apr 2005, 22:41
The 738 cargo hold is FAA fire category C (Pressurized but unventilated) How are the categories made up? Does class C mean anything else apart from what is in brackets ie min/max time for supression? Do all 737s have fire DEtection in the hold ( i realise that not all have PROtection)
prop jocket
3rd May 2005, 20:56
Winston,
I was involved in the all operators consultation after the Valuejet incident, so I'll try and answer your questions. There's a bit more to it than this, but in a nutshell:-
Class A - the crew have access to the compartment and do so during their normal duties. Hand held extinguishing equipment can be easily brought to bear. Wardrobes are an example of class A.
Class B - the crew have access to the compartment in flight, but wouldn't normally do so. Therefore fire inspections are performed regularly as part of the normal operation of the aircraft.
Class C - sealed, fire proof linings, detection and extinguishing systems installed, giving fire indications on and controllable from the flight deck.
Certification of class C compartments is sub divided dependent upon the duration of suppression:
Type 1: Initial suppression certified for 90 mins, extended to 180 mins if a secondary metered bottle is installed.
Type 2: One shot bottle, certified for 90 mins.
Certification requirement is for 3% average (FAA) or 3% point to point (EASA).
Class D - no access in flight, and either detection but no suppression, or neither detection nor suppression. protection is given by it being air tight and flame proof linings.
Not all 737 a/c are class C. 737 NG's are as standard, but EASA bless them haven't approved the Boeing installation for retrofit to earlier models even though it's identical to the approved one in the NG's. You work that out!
Hope this has answered the question for you.