AD/DHC-8/116 Fuel Tank Lightning Protection (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes

AD/DHC-8/116 Fuel Tank Lightning Protection 4/2006

Applicability:	DHC-8 Series 400 aeroplanes, serial numbers (S/N) 4005, 4006, 4008 through 4010, 4012 through 4015 and 4018 through 4040.
Requirement:	1.    For aeroplanes S/N 4005, 4006, 4008 through 4010, 4012 through 4015 and 4018 through 4040 - If not previously accomplished, incorporate ModSum 4-113299.  Approved instructions for incorporating ModSum 4-113299 are detailed in the Accomplishment Instructions of Bombardier Alert Service Bulletin A84-28-02 dated 7 February 2001 or later revisions approved by the Director, Aircraft Certification, Transport Canada.
2.    For aircraft serial numbers 4006, 4008, 4012 through 4015 and 4018 through 4027 - If not previously accomplished, incorporate ModSum 4-113192.  Approved instructions for incorporating ModSum 4-113192, are detailed in the Accomplishment Instructions of Bombardier Service Bulletin 84-28-01 dated 19 December 2000 or later revisions approved by the Director, Aircraft Certification, Transport Canada.
Note:  Transport Canada AD CF-2001-14 refers.
Compliance:	For Requirements 1 and 2 - Within 30 days after the effective date of this Directive.
This Airworthiness Directive becomes effective on 13 April 2006.
Background:	Transport Canada has advised that two potential problems have been identified with the wing fuel tanks which, if not corrected, could compromise the lightning protection of the aircraft.  The first issue is the possible lack of clearance between the fuel tank vent line and rib structures at 20 wing stations (10 in each wing).  The second issue is a potential fouling condition between #1, #2 and #5 fuel probes and the wing tank structure.

James Coyne
Delegate of the Civil Aviation Safety Authority

2 March 2006