AD/J4100/22 Main Wheel Tie Bolts (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.

BAe Systems (Operations) Jetstream 4100 Series Aeroplanes

AD/J4100/22 Main Wheel Tie Bolts 4/2008 DM

Applicability:

All Model Jetstream Series 4100 aircraft.

Requirement:

1.    Carry out the Accomplishment Instructions detailed in paragraph 2 of BAE Systems Service Bulletin (SB) J41-32-058 Revision 1, or later EASA approved revision.

a.     At every 5^th main wheel tyre change, discard and replace the main wheel tie bolts in accordance with paragraph 2 of SB J41-32-058 Revision 1, or later EASA approved revision.

b.    For main wheel tie bolts previously subject to UK CAA AD 002-05-97, the five allowable tyre changes shall continue to be counted from the initial installation of the bolts when new;

OR,

2.    From the effective date of this Directive, inspect the main wheel tie bolts at each tyre change in accordance with the instructions detailed in paragraph 2 of SB J41-32-058 Revision 2, or later EASA approved revision.  Main wheel tie bolts maintained in accordance with this requirement are not subsequently eligible for compliance with Requirement 1.

Incorporation of SB J41-32-072 Revision 1, or later EASA approved revision, which introduces a modified main wheel assembly with larger diameter wheel tie bolts, constitutes terminating action for the requirements of this Directive.

Note:  UK CAA AD G-2005-0022 refers.

Compliance:

1.    At the next main wheel tyre change after the effective date of this Directive.

2.    From the effective date of this Directive.

This Airworthiness Directive becomes effective on 20 February 2008.

Background:

Following a series of failures of 5/16-inch diameter main wheel tie bolts which could have resulted in wheel and/or tyre failure, and with consequential damage or impaired directional control, SB J41-32-058 Revision 1 was mandated by CAA AD 002-05-97.

Revision 2 of SB J41-32-058 covers revised Dunlop vendor Service Bulletin AHA1837-32-1157 at Revision 4 which changes the maintenance procedure for the main wheel tie bolts and, if carried out, removes the retirement life that was imposed on the bolts.

David Villiers
Delegate of the Civil Aviation Safety Authority

15 February 2008