89. Which operation would be described as preventive maintenance?

Title 14 Appendix A to Part 43—Major Alterations, Major Repairs, and Preventive Maintenance

(a) General. No person may operate a civil aircraft of U.S. registry—

(c) Preventive maintenance. Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations:
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(4) Servicing landing gear wheel bearings, such as cleaning and greasing.
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