Appendix A APPENDIX A. DEFINITIONS
1. Airworthy. An aircraft, aircraft engine, or component that conforms to its type design and is safe to operate.
2. Air Commerce. Foreign air commerce, interstate air commerce, the transportation of mail by aircraft, the operation of aircraft within the limits of a Federal airway, or the operation of aircraft that directly affects, or may endanger safety in, foreign or interstate air commerce.
3. Aircraft Maintenance Manual (AMM). A manual developed by the manufacturer of a particular airplane that contains information necessary for the continued airworthiness of that airplane.
4. Appliance. Any instrument, mechanism, equipment, part, apparatus, appurtenance, or accessory, including communications equipment, that is used or intended to be used in operating or controlling an aircraft in flight, is installed in or attached to the aircraft, and is not part of an airframe, engine, or propeller.
5. Approved. Unless used with reference to another person, approved by the Administrator.
6. Civil Aircraft. An aircraft (except a public aircraft).
7. Component Maintenance Manual (CMM). A manual developed by a manufacturer that contains information necessary for the continued airworthiness of a particular component.
8. Continued Airworthiness. Certified aircraft, engines, propellers, and appliances are safe to operate for the intended purpose; they are maintained safely throughout their service life; the product meets its type design; and is in condition for safe operation.
9. Governmental Function. An activity undertaken by a government, such as national defense, intelligence missions, firefighting, search and rescue, law enforcement (including transport of prisoners, detainees, and illegal aliens), aeronautical research, or biological or geological resource management.
10. Instructions for Continued Airworthiness (ICA). The information developed in accordance with (IAW) applicable airworthiness requirements that include the applicable inspection tasks, intervals, methods, processes, and airworthiness limitations (AL) to keep the product airworthy throughout its operational life.
11. Maintenance. Inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance.
12. Maintenance and Inspection Instructions. Information that provides, for each part of the airplane and its engines, auxiliary power units, propellers, accessories, instruments, and equipment, the recommended periods at which they should be cleaned, inspected, adjusted, tested, lubricated, and the degree of inspection, the applicable wear tolerances, and work recommended at these periods needed to provide for the continued A-1
Appendix A airworthiness of the airplane. The recommended overhaul periods and necessary crossreference to the Airworthiness Limitation Section (ALS) of the manual are also included.
13. Maintenance Planning Data (MPD). Data developed by the manufacturer of a particular airplane which contains the information each operator of that airplane needs to develop a customized, scheduled maintenance or inspection program.
14. Major Alteration. An alteration not listed in the aircraft, aircraft engine, or propeller specifications that might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness. That is not done according to accepted practices or cannot be done by elementary operations.
15. Major Repair. A repair, that if improperly done, might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness, or that is not done according to accepted practices or cannot be done by elementary operations.
16. Person. An individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity. It includes a trustee, receiver, assignee, or similar representative of any of them.
17. Products. Products are certified aircraft, engines, propellers, and appliances.
18. Public Aircraft. Refers to any of the following:
18.1. Except with respect to an aircraft described in Title 49 of the United States Code (49 U.S.C.) § 40102 (a)(41), an aircraft used only for the United States (U.S.)
Government, except as provided in 49 U.S.C. § 40125(b).
18.2. An aircraft owned by the Government and operated by any person for purposes related to crew training, equipment development, or demonstration, except as provided in § 40125(b).
18.3. An aircraft owned and operated by the government of a State, the District of Columbia, or a territory or possession of the U.S. or a political subdivision of one of these governments, except as provided in § 40125(b).
18.4. An aircraft exclusively leased for at least 90 continuous days by the government of a State, the District of Columbia, or a territory or possession of the U.S. or a political subdivision of one of these governments, except as provided in § 40125(b).
18.5. An aircraft owned or operated by the armed forces or chartered to provide transportation to the armed forces under the conditions specified by § 40125(c).
19. Time in Service. With respect to maintenance time records, the time from the moment an aircraft leaves the surface of the earth until it touches it at the next point of landing. This is expressed in hours, cycles, or both.
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Appendix B APPENDIX B. ACRONYMS.
14 CFR Title 14 of the Code of Federal Regulations AC Advisory Circular ACO Aircraft Certification Office AD Airworthiness Directive AFS Flight Standards Service ALI Airworthiness Limitation Item ALS Airworthiness Limitation Section AMM Aircraft Maintenance Manual CMM Component Maintenance Manual FAA Federal Aviation Administration ICA Instructions for Continued Airworthiness NTSB National Transportation Safety Board B-1
Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by contacting the Flight Standards Directives Management Officer at 9-AWA-AFS-140-Directives@faa.gov.
Subject: AC 91-91, Maintaining Public Aircraft Date: _____________________ Please check all appropriate line items:
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