AD 2017-05-51 Airworthiness Directives; Bell Helicopter Textron Canada Helicopters

This AD becomes effective April 25, 2017 to all persons except those persons to whom it was made immediately effective by Emergency AD 2017-05-51, issued on March 3, 2017, which contains the requirements of this AD.

(1) The Manager, Denver Aircraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Matthew Bryant, Aerospace Engineer, Denver Aircraft Certification Office, FAA, Technical Operations Center, 26805 East 68th Avenue, Room 214, Denver, CO 80249; fax (303) 342-1088; email Matthew.Bryant@faa.gov. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC.

Joint Aircraft Service Component (JASC) Code: 2150, Cabin Cooling System.

Before further flight, and thereafter at intervals not to exceed 25 hours time-in-service: (1) Inspect the motor and condenser blower to determine whether the motor is attached to the shroud. (i) If the motor is not attached, before further flight: (A) Inspect the collective flight control tube for loss of protective primer, a scratch, any gouging, and a dent. If there is any loss of protective primer, a scratch, any gouging, or a dent, repair or replace the control tube. (B) Inspect the area under the forward transmission cowling for loss of protective primer, a scratch, any gouging, and a dent. Inspect each wiring harness for any cuts, chafing, and exposed wires. If there is any loss of protective primer, a scratch, any gouging, a dent, or if any wiring harness has a cut, chafing, or an exposed wire, repair or replace the affected parts. (C) Inspect the area under the forward transmission cowling for the three fasteners as depicted in Figure 1 of SB 429-201-1. Also inspect for the crimp-on external fan retaining ring (crimp ring) and the slotted fan drive spring (commonly known as a roll pin), which may have fallen loose with the motor. Remove any fasteners, the crimp ring, and the roll pin if found detached. (D) Deactivate the air conditioning system by following the instructions in Procedure, paragraphs B.2.d.i. through B.2.d.v., of SB 429-201-1. (ii) If the motor is attached to the shroud but a fastener is missing or loose, before further flight: (A) Remove any detached fasteners found in the area under the forward transmission cowling. (B) Deactivate the air conditioning system as follows: ( 1 ) Pull and red collar the air conditioning COND circuit breaker. ( 2 ) Pull and red collar the air-conditioning COMP circuit breaker. ( 3 ) Remove the compressor drive belt. ( 4 ) Remove the condenser blower assembly. (2) Deactivating the air conditioning system as required by paragraph (e)(1) of this AD constitutes terminating action for the repetitive inspections required by paragraph (e)(1) of this AD. (3) If the air conditioning system is deactivated as required by paragraph (e)(1) of this AD, within 10 days after completing the inspection, report the information requested in Appendix 1 to this AD by mail to the Manager, Denver Aircraft Certification Office, FAA, Technical Operations Center, 26805 East 68th Avenue, Room 214, Denver, CO 80249, ATTN: Matthew Bryant; by fax to (303) 342-1088; or by email to Matthew.Bryant@faa.gov.

This AD defines the unsafe condition as a condenser blower motor (motor) detaching from the condenser blower support (shroud). This condition could lead to failure of the primary flight controls and subsequent loss of helicopter control.