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AD 75-18-06 ACTIVE

Tail Rotor Pitch Control
Key Information
AD Number 75-18-06 Status Active
Effective Date September 19, 1975 Issue Date Not specified
Docket Number Unknown Amendment 39-2345
Product Type ["Aircraft"] Product Subtype ["Rotorcraft"]
CFR Part --- - Part 39 CFR Section N/A
Citation This information is not available.
Applicability
Manufacturer(s) Scotts-Bell 47 Inc
Model(s) 47B 47B3 47D 47D1 47E 47G 47G-2 47H-1
Regulatory Text

75-18-06 BELL: Amendment 39-2345. Applies to Bell Models 47B, 47B-3, 47D, 47D-1, 47E, 47G, 47G-2, and 47H-1 helicopters certificated in all categories that are equipped with a single-row ball bearing, P/N 47-641-146-1 (MRC R4AF4), in the tail rotor pitch control crosshead.

Compliance required within 10 hours' time in service for bearings with more than 40 hours' time in service on the effective date of this AD and prior to attaining 50 hours' time in service for bearings with less than 40 hours' time in service on the effective date of this AD.

To prevent possible failure of the tail rotor pitch control ball bearing due to inadequate lubrication, accomplish the following one-time inspection.

a. Disassemble the tail rotor pitch control crosshead assembly in accordance with Sections VI and VII, Models 47D-1, 47G, and 47G-2 Maintenance and Overhaul Instruction Manual, revised August 15, 1961, or in accordance with equivalent FAA approved procedures to expose the pitchchange bearing.

b. Inspect the bearing, P/N 47-641-146-1 (MRC P/N R4AF4) for grease dust shields.

c. Remove any pitch change bearings with two grease dust shields installed before further flight.

d. Install bearings P/N 47-641-146-1 (MRC P/N R4AF4) with only one grease dust shield installed and assemble and rig the tail rotor controls, in accordance with Sections VI and VII, Models 47D-1, 47G, and 47G-2 Maintenance and Overhaul Instruction Manual, revised August 15, 1961, or in accordance with equivalent FAA approved procedures.

e. This AD does not apply to the obsolete design, single-row ball bearings having a single grease dust shield, Norma Hoffman P/N S1RP and New Departure P/N 7R4AX1C. This AD does not apply to the duplex pitch change bearings, P/N 47-641-131-1.

This amendment becomes effective September 19, 1975.