(a) For each turbine engine powered rotorcraft and Category A
reciprocating engine powered rotorcraft, and for each Category B
reciprocating engine powered rotorcraft with engines of more than 900
cubic inches displacement, there must be approved, quick-acting fire
detectors in designated fire zones and in the combustor, turbine, and
tailpipe sections of turbine installations (whether or not such sections
are designated fire zones) in numbers and locations ensuring prompt
detection of fire in those zones.
(b) Each fire detector must be constructed and installed to withstand
any vibration, inertia, and other loads to which it would be subjected in
(c) No fire detector may be affected by any oil, water, other fluids,
or fumes that might be present.
(d) There must be means to allow crewmembers to check, in flight, the
functioning of each fire detector system electrical circuit.
(e) The writing and other components of each fire detector system in an
engine compartment must be at least fire resistant.
(f) No fire detector system component for any fire zone may pass
through another fire zone, unless --
(1) It is protected against the possibility of false warnings resulting
from fires in zones through which it passes; or
(2) The zones involved are simultaneously protected by the same
detector and extinguishing systems.