tivity, distortion, spurious radiation, AVC characteristics, or ability to meet environmental test conditions or any other changes which have an effect on the performance of the equipment are considered to be major appliance alterations. [Supp. 1, 18 F.R. 7387, Nov. 21, 1953, as amended by Supp. 3, 19 F.R. 4185, July 9, 1954; Supp. 5, 20 F.R. 7535, Oct. 8, 1955; Supp. 9, 23 F.R. 1718, Mar. 13, 1958; 24 FR. 5, Jan. 1, 1959] § 18.1-2 Procedures for handling certain typical major alterations or modifications (FAA policies which apply to § 18.1). Procedures for handling certain typical alterations or modifications are discussed in detail in § 18.30-17. [Supp. 1, 18 F. R. 7387, Nov. 21, 1953] § 18.1-3 Major repairs (FAA interpretations which apply to § 18.1). Repairs of the following types to an airframe, powerplant, propeller, or appliance are considered to be major repairs: (a) Airframe major repairs. (1) All repairs involving the strengthening, reinforcing, splicing and manufacturing of primary structural members or their replacement, when replacement is by fabrication such as riveting or welding, are considered airframe major repairs. The following are examples of such members: (2) The repair of damaged areas in metal or plywood stressed covering exceeding six inches in any direction; the repair of portions of skin sheets by making additional seams; splicing of skin sheets. (3) Repair of three or more adjacent wing or control surface ribs or leading edge of wings and control surfaces, between such adjacent ribs. (4) Repair of fabric covering involving a greater area than required to repair two adjacent ribs; replacement of fabric on fabric covered components such as wings, fuselages, stabilizers, and control surfaces. (5) Rebuilding, including rebottoming, of removable or integral fuel tanks, and oil tanks. (b) Powerplant major repairs. Repairs such as the following are considered powerplant major repairs: (1) Any maintenance operation requiring (i) the separation or disassembly of a crankcase or crankshaft of an engine equipped with an integral supercharger and/or propeller reduction gearing; (ii) disassembly of a nonfloat type carburetor or fuel injection unit used with such engines; or, (iii) top overhaul of such engines. (2) Special repairs to structural engine parts by welding, plating, metalizing or other methods. (See § 18.30-14 (a) (10) through (12) for details.) (c) Propeller major repairs. Repairs of the following types are considered to be major propeller repairs: (1) Any repairs to or straightening of steel blades. (2) Repairing or machining of steel hubs. (3) Shortening of blades. (4) Retipping of wood propellers. (5) Replacement of outer laminations on fixed pitch wood propellers. (6) Repairing elongated bolt holes in the hub of fixed pitch wood propellers. (7) Inlay work on wood blades. (8) All repairs to composition blades. (9) Replacement of tip fabric. (10) Replacement of plastic covering. (11) Repair of propeller governors. (12) Repair of balance propellers of rotocraft. (13) Overhaul of controllable pitch propellers (see § 18.30-15 (c) (1)). (14) Repairs to deep dents, cuts, scars, nicks, etc., and straightening of aluminum blades, such as described in § 18.30-15 (b) (3) (iii). (15) The repair or replacement of internal elements of blades. (d) Appliance major repairs. Repairs to appliances which are complex repair operations requiring the use of skilled techniques and/or special tools and test equipment not available to a mechanic working outside of an appliance shop are considered to be a major repair. Major repairs to appliances include, but are not limited to the following: (ii) (5) Mechanical accessories. (1) Pressure type carburetor overhaul. Overhaul of pressure type fuel, oil or hydraulic pumps. [Supp. 1, 18 F. R. 7387, Nov. 21, 1953] § 18.1-4 Minor alterations (FAA interpretations which apply to § 18.1). Changes such as the following to an airframe, powerplant, propeller, or appliance are considered minor aircraft alterations: (a) Airframe minor alterations. Changes such as listed below are considered to be airframe minor alterations: (1) Optional equipment on aircraft specification. The installation or removal of specific items of optional equipment listed in the aircraft specification when such installation is made in accordance with the manufacturer's instructions. (2) Equipment of equal or less weight. The installation or removal of equipment of equal or less weight and in the same location as that listed as optional equipment in the aircraft specification. (3) Changes to improve service life. Changes of a minor nature made to structural and nonstructural elements 3 Copies of aircraft specifications may be obtained from FAA, Office of Aviation Information, Washington 25, D. C. for the purpose of improving the service life or reducing maintenance costs. (4) Weight and/or balance change. All changes to the empty weight or empty balances which do not result in an increase in the certificated maximum weight or center of gravity limits of the aircraft. (b) Powerplant minor alterations. Any powerplant alteration other than listed as a major alteration under § 18.1(1) (b) is considered to be a minor powerplant alteration. The following are examples of powerplant minor alterations: (1) Alterations to supporting brackets or braces of units of the powerplant which do not adversely affect the structural integrity of such parts. (2) Changes to the cowling which do not affect engine cooling, such as revisions to mounting bracket attachments. (3) The alteration or conversion of an aircraft engine by simple substitution of parts of different design or addition of FAA approved parts in accordance with approved practices and in conformity to the engine manufacturer's or FAA instructions. Any (c) Propeller minor alterations. propeller alteration other than defined as a major alteration under § 18.1-1 (c) is considered to be a minor propeller alteration. The following are examples of minor propeller alterations: (1) Initial installation of a propeller spinner. (2) Changes to the basic design of, or the relocating of brackets or braces of the propeller controls. (3) Changes to the basic design of propeller control rods or cables. (d) Appliance minor alterations. Changes to the basic design made in accordance with the "Administrator of the Federal Aviation Agency" approved recommendations of the appliance manufacturer, or in accordance with an FAA Airworthiness Directive are considered to be minor appliance alterations. (1) Radio communication and navigation equipment approved under type certification or the Technical Standard Order System. Minor alterations include but are not limited to substitution of standard parts of one manufacturer for those of another. Such parts include but are not limited to tubes, semiconducting devices such as crystal diodes and transistors, resistors, capacitors, chokes, tube sockets, relay and standard hardware. [Supp. 1, 18 F. R. 7388, Nov. 21, 1953, as amended by Supp. 5, 20 F. R. 7535, Oct. 8, 1955; Supp. 9, 23 F.R. 1718, Mar. 13, 1958; 24 F.R. 5, Jan. 1, 1959] § 18.1-5 Minor repairs (FAA interpretations which apply to § 18.1). Repairs of the following types to an airframe, powerplant, propeller, or appliance are considered to be minor repairs: (a) Airframe minor repairs—(1) Nonstructural members. Repairs to nonstructural members which may affect the airworthiness of an aircraft, such as: Cowlings. Wing and control surface fairings. Windshields. (2) Tanks. Patching and repairing of leaks in nonintegral fuel, oil, hydraulic, and de-icer fluid tanks. (3) Ribs, leading and trailing edges, tip strips. The repair of: Not more than two adjacent wing or control surface ribs of a conventional type (wood or metal); the leading edge of wing and control surfaces between two adjacent wing or control surface ribs; the trailing edge of wings, control surfaces, and flaps; the wing and control surface tip strips. (4) Fabric covering. Patching of fabric involving replacement of fabric covering of surfaces when such replacement is of an area not greater than that required to repair two adjacent ribs. (5) Metal or plywood stressed covering. The patching of holes in metal or plywood stressed covering not to exceed 6 inches in any direction when ribs, stringers, bulkheads, and reinforcements are not directly affected. (6) Replacement of components. Replacement of components or complete units such as listed below with parts supplied by the original manufacturer or manufactured in accordance with approved drawings: Wings. Replaceable wing tips. Control surfaces (fixed and movable) and control cables. Wing or control surface bracing (struts or wires). Floats. Landing gears. Tail wheel assemblies. Engine mounts (prefabricated and bolted Appliances such as: instruments, hydraulic or electrical actuating units of components, cabin heaters, radio units, auto-pilots. (b) Powerplant minor repairs. Any powerplant repair other than listed under § 18.1-3 as a major repair, or under § 18.1-6 as preventive maintenance, is considered to be a minor repair. The following are examples of powerplant minor repairs: (1) Engine top overhauls. Engines which have neither an integral supercharger nor integral propeller reduction gearing, consisting of the following: (i) Removal of cylinders. (ii) Grinding valves and removing carbon. (iii) Fitting new rings. (iv) Adjustments of valve gear or replacement of parts in valve mechanism outside of the crank case. (2) Engine complete overhauls. Complete overhauls of engines which have neither an integral supercharger nor integral propeller reduction gearing. (3) Replacement of components. The replacement of components not a part of the basic structure of the engine, such as carburetors, magnetos, ignition harnesses, on engines of any horsepower. (4) Replacement of accessories. The replacement of components such as generators, starters, fuel pumps, vacuum pumps, hydraulic pumps, and oil coolers on engines of any horsepower. (c) Propeller minor repairs. Repairs such as the following to propellers are considered to be propeller minor repairs: (1) Repairing dents, cuts, scars, scratches, nicks, leading edge pitting of aluminum blades, provided removal or treatment does not materially affect the strength, weight, balance, or performance of the propeller. (See § 18.30-15 (b) (3) (iii).) (2) Repairing dents, cuts, scars, scratches, nicks, and small cracks parallel to the grain of wood blades. (See § 18.30-15 (b) (2) (i).) (3) Removal and installation of propellers. (4) The assembly and disassembly of propellers to the extent necessary to permit: (i) Assembly of propellers partially disassembled for shipment and not requiring the use of balancing equipment; (ii) The accomplishment of routine servicing and inspection; (iii) Replacement of parts other than those which normally require the use of skilled techniques, special tools and test equipment. (Reference see § 18.30-1 (a).) (5) Balancing of fixed pitch and ground adjustable propellers. (6) Refinishing of wood propellers. (d) Appliance minor repairs. Any repair to an appliance which would not be defined as a major appliance repair under § 18.1-1 (d) or preventive maintenance under § 18.1-6 is considered to be a minor appliance repair. [Supp. 1, 18 F. R. 7388, Nov. 21, 1953, as amended by Supp. 3, 19 F. R. 4185, July 9, 1954] § 18.1-6 Preventive maintenance (FAA interpretations which apply to § 18.1). The following are considered to be typical preventive maintenance operations: Removal, installation, and repair of landing gear tires. Replacing of elastic shock absorber cords on landing gear. Servicing landing gear shock struts by adding oil and/or air. Servicing landing gear wheel bearings, such as cleaning and greasing. Replacing defective safety wiring or cotter keys. Any lubrication not requiring disassembly other than removal of nonstructural cover plates, cowlings, fairings, etc. Making simple fabric patches not requiring rib stitching or the removal of structural parts or control surfaces. Replenishing hydraulic fluid in hydraulic reservoir. Refinishing decorative coating of fuselage, wings, and tall group surfaces (excluding balanced control surfaces), fairings, cowling, landing gear, cabin or cockpit interior not requiring removal or disassembly of any primary structure or operation system such as hydraulic or fuel system. Applying preservative or protective material to components where no disassembly of primary structure or operation systems is involved, such as seaplane preservation (paralkatone to control cables, etc.), anticorrosive paint to structures or components where such coating is not prohibited or is not contrary to good practices. Cabin or cockpit interior work (repairing upholstery and decorative furnishings) which does not require disassembly of any primary structure or operation system or interfere with an operating system or affect primary structure of the aircraft. Small simple repairs to fairings, nonstructural cover plates, cowlings, such as drilling stop holes (section 18.30), small patches and reinforcements not making any change to contour where such change would interfere with proper air flow. Replacing of side windows where such work does not interfere with structure or any operating system such as controls, electrical equipment, etc. Replacing of safety belts. Replacing of seats or seat parts wth replacement parts approved for the aircraft, not involving disassembly of any primary structure or operating system. Trouble shooting and repairing broken circuits in landing light wiring circuits. Replacing of bulbs, reflectors, and lenses of position and landing lights. Replacing of wheels and skis where no weight and balance computation is involved. Replacing of any cowling not requiring removal of the propeller or any disconnecting of flight controls. Replacing or cleaning and setting of spark plug gap clearance. Replacing of any hose connection except hydraulic connections. Replacing prefabricated fuel lines. The removal and installation of glider wings and tail surfaces which are specifically designed for quick removal and installation when such removal and installation can be accomplished by the pilot. [Supp. 1, 18 F.R. 7389, Nov. 21, 1953, as amended by Supp. 10, 23 F.R. 5378, July 16, 1958] § 18.10 GENERAL Persons authorized to perform maintenance, preventive maintenance, repairs, and alterations. No person shall perform maintenance, preventive maintenance, repairs, or alterations on certificated aircraft coming within the applicability of this part or on any component thereof, except as provided as follows: NOTE: The Communications Act of 1934, as amended, and the rules and regulations of the Federal Communications Commission require that all transmitter adjustments or tests during or coincident with the installation, servicing, or maintenance of a radio station licensed by the Federal Communications Commission which may affect the proper operation of such station shall be made by or under the immediate supervision and responsibility of a person holding a first or second-class radio operator license issued by the Federal Communications Commission, either radiotelephone or radiotelegraph as may be appropriate for the class of station concerned, who shall be responsible for the proper functioning of the station equipment. (a) A certificated mechanic or a person who works under the direct supervision of such mechanic may perform maintenance, repairs, and alterations on aircraft or aircraft components including related appliances, appropriate to his rating, but excluding major repairs and alterations to propellers and all repairs and alterations to instruments. (b) An appropriately rated repair station may perform maintenance, repairs, and alterations on aircraft or aircraft components, including propellers and appliances, as provided in Part 52 of this subchapter. (c) A certificated pilot may perform, on aircraft owned or operated by him, except aircraft used in air carrier service, such preventive maintenance as may be authorized by the Administrator. (d) A manufacturer shall be subject to the requirements of paragraphs (a) and (b) of this section, except that he may rebuild or alter: (1) Any product manufactured by him under a type or production certificate, or (2) Any product manufactured by him and approved under the terms of a Technical Standard Order or Product and Process Specification issued by the Administrator. (e) An appropriately certificated air carrier may perform maintenance, repairs, and alterations on aircraft or aircraft components, including propellers and appliances, as provided for in its continuous airworthiness maintenance and inspection program and its maintenance manual. It may also perform maintenance, repairs, and alterations on any aircraft or aircraft components, including propellers and appliances, owned or operated by another air carrier as provided for in the applicable continuous airworthiness maintenance and inspection program and maintenance manual of such other air carrier. (f) A certificated commercial operator may perform maintenance, repairs, and alterations on its own aircraft or aircraft components, including propellers and appliances, as provided for in its continuous airworthiness mainte nance and inspection program and its maintenance manual. [21 F.R. 4863, June 30, 1956, as amended by Amdt. 18-1, 22 F.R. 1631, Mar. 14, 1957] § 18.10-1 Persons authorized to perform maintenance, repairs, and alterations (FAA interpretations which apply to § 18.10(a)). Direct supervision means that the supervising mechanic personally maintains such observation of the work being performed as is necessary to insure that the work is being performed properly, and the supervising mechanic is readily available in person for consultation with the person performing the work. [Supp. 1, 18 F.R. 7389, Nov. 21, 1953] § 18.11 Persons authorized to approve maintenance, repairs, and alterations. NOTE: Section 43.21 of this subchapter requires that when an aircraft has undergone any repair or alteration which may have appreciably changed its flight characteristics or substantially affected its operation in flight, such aircraft, prior to carrying passengers, shall be test flown. (a) Maintenance, minor repairs, and minor alterations. Except for preventive maintenance performed as authorized in § 18.10(c), which shall not require approval, no airframe, powerplant, propeller, or appliance which has undergone maintenance, minor repair, or minor alteration may be approved and returned to service except by one of the following: (1) An appropriately rated certificated mechanic; or (2) An appropriately rated certificated repair station; or (3) An appropriately certificated air carrier; or (4) A manufacturer, if the product has been rebuilt or altered by the manufacturer under the provisions of § 18.10 (d); or (5) A certificated commercial operator. (b) Major repairs and major alterations. No airframe, powerplant, propeller, or appliance, which has undergone any major repair or major alteration shall be returned to service until such repair or alteration has been examined, inspected, and approved as airworthy by one of the following: NOTE: A major repair or major alteration whose design has not previously been approved by the Administrator may require the |