Document ID: chunk:federal_register_of_legislation:F2006B08792:body:0:p1
Version: federal_register_of_legislation:F2006B08792
Segment Type: other
Provision Reference: 
Character Range: 4–3101

Douglas DC3 Series Aeroplanes

    AD/DC3/15
    Amdt 2

    Engine Nacelle Fire Protection - Modifications 4/84

    Applicability: All models.

                 Requirement: 1. Install a fire detection system for each engine nacelle as follows:- Fire Detectors:
(a)     Install a continuous type detector or a minimum of six (6) unit detectors in the accessory compartment. Mount unit detectors or portion of the continuous type detector at suitable locations on or near the forward face of the firewall and dispose as evenly as possible about the nacelle axis. In installations where the airstream from the oil cooler is discharged into the accessory compartment, mount at least one unit detector or portion of a continuous detector in the path of the airstream.

                 (b)     All detectors used shall be of an approved type. Detector Circuits:
(a)     Provide separate independent detector circuits for each nacelle.

(b)    Provide a test switch in the cockpit in each detector circuit and arrange the circuit so that the operation of the test switch checks the circuit protection, the indicator lamps, and the continuity of the detector wiring.

                 Indicators:

(a)     Provide separate indicators in the cockpit for each nacelle; each indicator shall consist of two red lamps connected in parallel.

(b)     Ensure that the indicating lights are in the field of vision of the pilot and co- pilot and are separated sufficiently to prevent confusion as to the source of the fire.

(c)     In addition to indicating lights, install an audible warning device, which is capable of being silenced and common to all detector circuits, in the cockpit. Ensure that the noise emitted by such device is distinctive from that emitted by any other audible warning device in the cockpit.

                 Fire Extinguisher System:

                 Modify the existing fire extinguisher installation to comply with the following requirements:-

(a)     Ensure that two separate charges of extinguishant are available to each nacelle. Each extinguishant charge shall consist of at least seven (7) pounds of carbon dioxode or six (6) pounds of methyl bromide.
 COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
 SCHEDULE OF AIRWORTHINESS DIRECTIVES

                (b)     Plumb the extinguishant to an accessory compartment spray ring. Where the airstream from the oil cooler discharges into the accessory compartment, arrange the extinguisher spray line so that an adequate amount of extinguishant is discharged into the oil cooler honeycomb.

           Note: Existing installations, where portion of the extinguishant is discharged into the carburettor air intake, may be retained if not more than 25 per cent of the extinguishant, by weight, enters the intake.

                (c)     Ensure that extinguisher lines and spray rings forward of the firewall are of fireproof construction, except that short flexible lengths may consist of fire- resistant coupled hose assemblies.

                (d)     Where the