Airworthiness Directive · Amendment 39-19134 · Main rotor system
The Enstrom Helicopter Corporation Helicopters
This AD applies to the Enstrom Helicopter Corporation (Enstrom) Model F-28, F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-28F-R, TH-28, 280, 280C, 280F, 280FX, 480, and 480B helicopters, certificated in any category, with a rod end bearing assembly (bearing assembly) P/N 01-824-08E-011, 09455-01-824-08E-011, ECD091-1, ASMK8T, M81935/1-08K, MS21242S8K, or MTK8 installed.
We are adopting a new airworthiness directive (AD) for the Enstrom Helicopter Corporation (Enstrom) Model F-28, F-28A, F-28C, F- 28C-2, F-28C-2R, F-28F, F-28F-R, TH-28, 280, 280C, 280F, 280FX, 480, and 480B helicopters. This AD requires inspecting certain rod end bearing assemblies. This AD is prompted by an accident. The actions of this AD are intended to prevent an unsafe condition on these helicopters.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(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.
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.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
