AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BELL 407/9 Amdt 1 and issues the following AD under subregulation 39.1 (1) of CAR 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 Canada (BHTC) 407 Series Helicopters
AD/BELL 407/9
Amdt 2
Tailboom Skin 8/2002 DM
Applicability: Model 407 helicopters, serial numbers 53000 through 53475. Requirement: 1. For aircraft fitted with tailbooms P/N 407-030-801-101 and -105:
- Inspection:
(i). Unless modification of the tailboom in accordance with Bell Helicopter Textron Canada (BHTC) Alert Service Bulletin (ASB) 407-01-48 dated 20 December 2001 has been accomplished, visually inspect the tailboom in accordance with Part I and Part II of BHTC ASB 407-99-26 Revision C, dated 15 January 2002.
(ii). For tailbooms modified in accordance with ASB 407-01-48, visually inspect the tailboom in accordance with Part IV and V of BHTC ASB 407-01-48.
b. Modification:
Modify the tailboom in accordance with BHTC ASB 407-101-48.
Create a new tailboom Historical Record sheet indicating time when ASB 407- 01-48 was embodied and assign a life limit of 5,000 hours.
2. For aircraft fitted with tailbooms P/N 407-030-801-107:
Create a new tailboom Historical Service Record sheet, assign a life limit of 5,000 hours, and inspect the tailboom in accordance with Part IV and Part V of BHTC ASB 407-01-48.
3. Life limit:
Tailbooms P/N 407-530-014-101, -103 and 407-030-801-107 are to be removed from service at 5,000 hours and replaced with a serviceable part.
If a crack is found on the tailboom skin as a result of Requirement 1 or 2 inspections, before further flight, replace the tailboom.
Note: Transport Canada AD CF-1999-17R2 refers.
Compliance: 1. a. (i). For Part I of ASB 407-99-26: Inspect before the first flight of each day
after 26 June 2000.
For Part II of ASB 407-99-26: Inspect within 50 hours time in service after 26 June 2002, and thereafter at intervals not to exceed 50 hours time in service.
This Directive shall be entered on the Maintenance Release as maintenance required. The visual inspection required by Part I of ASB 407-99-26 may be performed by the Pilot in Command who has been trained to do the inspection by an appropriately qualified person, in which case, a copy of the Requirement document and this Directive are to be carried in the aircraft.
(ii). Within 150 hours time in service after 26 June 2002, and thereafter at intervals not to exceed 150 hours time in service.
b. Within 600 hours time in service after 26 June 2002, but not later than 31 January 2003.
2. Inspect within 150 hours time in service after 26 June 2002, and thereafter at intervals not to exceed 150 hours time in service.
3. With effect from 26 June 2002.
This Amendment becomes effective on 26 June 2002.
Background: There have been several reports of cracks to the tailboom skin on the left side of the horizontal stabiliser. The cracks were found by normal visual inspection. The inspections required by this directive are intended as an interim measure pending completion of a design change to the tailboom skin.
Amendment 1 limited the applicability to those helicopters equipped with certain part number tailbooms. BHTC recently introduced a new tailboom with a chemically milled skin which is not subject to the inspections required by this Directive.
Amendment 2 is issued in response to a revision of the related Transport Canada AD which introduces modifications to some of the existing tailbooms, a life limitation of 5,000 hours, and a new inspection interval of 150 hours.
Amendment 1 of this Airworthiness Directive became effective on 1 November 2001.
The original issue of this Airworthiness Directive became effective on 9 September 1999.
David Alan Villiers
Delegate of the Civil Aviation Safety Authority 19 June 2002
The above AD is notified in the Commonwealth of Australia Gazette on. 26 June 2002.