AD/PC-12/43 Amdt 1 Crew Seats Backrest Tubes (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PC-12/43 and issues the following 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.

Pilatus PC-12 Series Aeroplanes

AD/PC-12/43 Amdt 1 Crew Seats Backrest Tubes 2/2006

Applicability:

All Model PC-12 and PC-12/45 airplanes equipped with backrest tubes on crew seats, with and without a recline system installed, as listed below:

1.    Backrest tubes on crew seats with a recline system:
Seat Part Numbers (P/Ns) 959.30.01.111, 959.30.01.112, 959.30.01.121 and 959.30.01.122.

2.    Backrest tubes on crew seats without a recline system:
Seat P/Ns 959.30.01.131, 959.30.01.132, 959.30.01.133 and 959.30.01.134.

Requirement:

New Component Life Limitations are mandated as follows:

1.    Backrest tubes on crew seats with a recline system:
Seat P/Ns 959.30.01.111, 959.30.01.112, 959.30.01.121 and 959.30.01.122 - 5000 flying hours.

2.    Backrest tubes on crew seats without a recline system:
Seat P/Ns 959.30.01.131, 959.30.01.132, 959.30.01.133 and 959.30.01.134 - 10000 flying hours.

Follow up action - All the replaced backrest tubes must be returned to Pilatus Aircraft Ltd, Structural Analysis Group ECE, CH-6371 Stans, Switzerland, including the following information:

- Crew seat Part Number (Seat P/N) and Serial Number (S/N),
- Aircraft Manufacturer Serial Number (MSN),
- Aircraft flying hours and number of flights; and
- Replacement date of the backrest tubes.

Note:  Switzerland FOCA AD HB-2005-470 and Pilatus PC-12 Maintenance Manual Temporary Revision No. 04-13 refers.

Compliance:

1.    For backrest tubes on crew seats with a recline system
(Seat P/Ns 959.30.01.111, 959.30.01.112, 959.30.01.121 and 959.30.01.122): Within the next 100 hours TIS after the effective date of this AD, but not later than 31 March 2006.

2.    For backrest tubes on crew seats without a recline system
(Seat P/Ns 959.30.01.131, 959.30.01.132, 959.30.01.133 and 959.30.01.134): Within the next 500 hours TIS after the effective date of this AD, but not later than 31 March 2006.

This Amendment becomes effective on 16 February 2006.

Background:

A report was received of the failure of a crew seat’s bucket assembly tubes, which was detected during a maintenance inspection.  Investigation revealed the tubes failed at the location of the energy device pins.  The lower tubes remained attached, but the upper parts were completely disconnected.  This could lead to reduced ability of the pilots to control the aircraft.

The original issue of this Directive required all crew seats above 6000 flying hours be inspected according to Pilatus PC-12 Service Bulletin No. 25-031, dated 21 July 2004. The Directive required, as an interim action, a one-time inspection of the pilot and co-pilot seat bucket assembly tubes for cracks, reporting of the inspection results and if necessary the replacement of the bucket assembly tubes.

This amendment specifies, as terminating action, the life limitations for the backrest tubes on crew seats with and without a recline system installed.

The original issue of this Airworthiness Directive became effective on 1 September 2004.

David Punshon
Delegate of the Civil Aviation Safety Authority

5 January 2006