AD/BELL 412/12 Amdt 5 - Vertical Fin Forward Spar (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Bell Helicopter Textron 412 Series Helicopters

AD/BELL412/12 Amdt 5

Applicability: All models.

Vertical Fin Forward Spar 6/93 DM

Requirement: 1. For helicopters fitted with fin spar cap P/N 212-030-447-001: Inspect the spar cap for cracks, corrosion and doubler debonding in accordance with Bell ASB 412-92- 65.

Note: FAA AD 93-02-07 refers.

Note: All fin spar caps P/N 212-030-447-001 should have been modified with a cold bonded doubler in accordance with Bell ASB 412-85-20 not later than 31 March 1986. Amendment 2 to this AD referred.

2. For helicopters fitted with fin spar cap P/N 212-030-447-101:

1. If cap thickness is greater than or equal to 0.190 inches when measured as shown in Bell ASB 412-86-24, no further action is required by this AD;

b. If cap thickness is less than 0.190 inches and the cap has been modified with a cold bonded doubler in accordance with Bell ASB 412-86-24, inspect for cracks, corrosion and doubler debonding using the inspection technique described in Part I of Bell ASB 412-92-65. Inspect at intervals not exceeding 100 hours time in service or 25 flight operation days, whichever occurs earlier, until replaced by a new cap P/N 212-030-447-101 in accordance with Bell ASB 412-92-65;

c. If cap thickness is less than 0.190 inches, but not less than 0.155 inches, and the cap has not been modified with a cold bonded doubler in accordance with Bell ASB 412-86-24, inspect for cracks in accordance with the inspection technique described in Part I of Bell ASB 412-85-20 Revision B. Inspect at intervals not exceeding 20 hours time in service or 5 flight operation days, whichever occurs earlier, until replaced with a new cap P/N 212-030-447-101 in accordance with Bell ASB 412-92-65.