COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

DH114 (Heron) Series Aeroplanes

AD/DH114/47 Fuel System - Modification and Component Relocation

Applicability: All models which have been modified to Connair Pty. Drawing 73B006 and associated engineering drawings and orders.

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DM

Requirement: 1. Remove low level shut-off valve from inboard fuel tanks and install in outboard fuel tanks.

2.    Remove submerged boost pump from outboard tanks and install in the inboard tanks.

Note: To accomplish items 1 and 2 above, it would be preferable to install the pre mod 73B006 outboard tank base plates and associated gaskets. However, should these not be available, existing base plates may be modified to suit, or new base plates manufactured from 2024-T3 0.125 inch aluminium alloy.

The inboard tank base plate low level cut-off valve aperture will require a blanking plate to be fitted using 2024-T3 0.125 inch aluminium alloy.

3.    Modify the electrical system as required to accomplish component re-location.

4.    Placard fuel boost pump selector switches as required.

5.    Incorporate a flight manual amendment to include variation in fuel management procedures.

6.    Amend maintenance manuals and maintenance schedules in a manner approved by the Secretary.

Compliance: Before further flight after 30 September 1985.

Background: A review of the modified fuel system has revealed shortcomings which necessitate remedial action.