AD 2017-26-03 Airworthiness Directives; The Enstrom Helicopter Corporation Helicopters

Makes named: enstrom. Read the applicability below — it usually turns on serial or part numbers too.

This AD becomes effective January 4, 2018.

A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 30 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW, Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.

(1) The Manager, Chicago ACO Branch, Compliance and Airworthiness Division, Aircraft Certification Service, FAA, may approve AMOCs for this AD. Send your proposal to: Manzoor Javed, Senior Aerospace Engineer, Chicago ACO Branch, Compliance and Airworthiness Division, Aircraft Certification Service, FAA, 2300 East Devon Ave., Des Plaines, IL 60018; telephone (847) 294-8112; email manzoor.javed@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.

(1) Within 5 hours time-in-service (TIS), using a 5X or higher power magnifying glass, inspect each main rotor damper bearing assembly for corrosion on the threaded portion of the rod end as shown in Figure 1 of Enstrom Service Directive Bulletin (SDB) No. 0127, Revision 1, dated October 6, 2017 (SDB 0127), for Model F-28, F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-28F-R, 280, 280C, 280F, and 280FX helicopters or Enstrom SDB No. T-058, dated August 2, 2017 (SDB T-058), for model TH-28, 480, and 480B helicopters, as appropriate for your model helicopter. If there is any corrosion, before further flight, replace the bearing assembly. (2) For Model F-28, F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-28F-R, 280, 280C, 280F, and 280FX helicopters, within 5 hours TIS, using a 5X or higher power magnifying glass, inspect each belt tension shaft rod end bearing assembly for corrosion on the threaded portion of the rod end as shown in Figure 1 of SDB 0127. If there is any corrosion, before further flight, replace the bearing assembly. (3) Within 10 days after completing the inspections required by paragraph (e)(1) and (e)(2) of this AD, report the findings of each inspection, including the helicopter owner, address, telephone number, email address, helicopter model, helicopter registration number, date of inspection, total hours TIS of the helicopter, total hours TIS of the bearing, bearing assembly serial number, location of any corrosion, and a description of any corrosion, by mail or email to the individual listed in paragraph (g)(1) of this AD.

This AD defines the unsafe condition as corrosion on a bearing assembly rod end thread. This condition could result in a crack in the bearing assembly, failure of the rod end resulting in loss of a main rotor blade, and loss of control of the helicopter.