AD/Bell 412/45 Emergency Floatation Reservoir Adapter (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.

Bell Helicopter Textron 412 Series Helicopters

AD/BELL 412/45 Emergency Floatation Reservoir Adapter 13/2005 TX

Applicability:

Bell Helicopter Textron Model 412 and 412EP helicopters, modified with Aeronautical Accessories, Inc. (AAI), Supplemental Type Certificate (STC) SH2820SO; or with AAI Parts Manufacturer Approval (PMA) reservoir assembly, part number (P/N) 212-372-050; or with adapter, P/N 212-371-002, installed.

Requirement:

1.    Vent the nitrogen from the reservoir assembly by following the Accomplishment Instructions, Part II - Floatation System Discharging, of AAI Alert Service Bulletin (ASB) No. AA-05005, Revision A dated 27 June 27 2005 or later FAA Approved revision.

2.    Remove the valve assembly and air line from the adapter, and inspect the counter bore depth (dimension D) as shown in Figure 1 of the ASB.

(a)   If dimension D, as depicted in Figure 1 of the ASB, does not exceed .860 inch, recharge the floatation system by following the Accomplishment Instructions, Part III - Floatation System Charging, and referring to Figures 2 and 3 of the ASB.

(b)   If dimension D, as depicted in Figure 1 of the ASB, exceeds .860 inch, replace the reservoir assembly and the adapter with serviceable parts.

3.    Discharging and recharging the floatation system and inspecting the counter bore depth dimension of the adapter shall be done in accordance with the specified portions of the ASB.

Note:  FAA AD 2005-20-38 Amendment 39-14335 refers.

Compliance:

1.    Within the next 24 hours time-in-service (TIS) or before the next emergency floatation supply bottle nitrogen charging after the effective date of this AD.

2.    Within the next 24 hours time-in-service (TIS) or before the next emergency floatation supply bottle nitrogen charging after the effective date of this AD.

2.    (b)   Before further flight after the effective date of this AD.

3.    From the effective date of this AD.

This Airworthiness Directive becomes effective on 9 November 2005.
Background:	The actions detailed in this AD are intended to prevent rupture of an adapter, uncontrolled jetting of pressurized gas from the nitrogen bottle, and subsequent injury to occupants or damage to the helicopter.

James Coyne
Delegate of the Civil Aviation Safety Authority

4 November 2005