43.3—Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations.

(a) Except as provided in this section and § 43.17, no person may maintain, rebuild, alter, or perform preventive maintenance on an aircraft, airframe, aircraft engine, propeller, appliance, or component part to which this part applies. Those items, the performance of which is a major alteration, a major repair, or preventive maintenance, are listed in appendix A.

(b) The holder of a mechanic certificate may perform maintenance, preventive maintenance, and alterations as provided in Part 65 of this chapter.

(c) The holder of a repairman certificate may perform maintenance, preventive maintenance, and alterations as provided in part 65 of this chapter.

(d) A person working under the supervision of a holder of a mechanic or repairman certificate may perform the maintenance, preventive maintenance, and alterations that his supervisor is authorized to perform, if the supervisor personally observes the work being done to the extent necessary to ensure that it is being done properly and if the supervisor is readily available, in person, for consultation. However, this paragraph does not authorize the performance of any inspection required by Part 91 or Part 125 of this chapter or any inspection performed after a major repair or alteration.

(e) The holder of a repair station certificate may perform maintenance, preventive maintenance, and alterations as provided in Part 145 of this chapter.

(f) The holder of an air carrier operating certificate or an operating certificate issued under Part 121 or 135, may perform maintenance, preventive maintenance, and alterations as provided in Part 121 or 135.

(g) Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter. The holder of a sport pilot certificate may perform preventive maintenance on an aircraft owned or operated by that pilot and issued a special airworthiness certificate in the light-sport category.

(h) Notwithstanding the provisions of paragraph (g) of this section, the Administrator may approve a certificate holder under Part 135 of this chapter, operating rotorcraft in a remote area, to allow a pilot to perform specific preventive maintenance items provided—

(1) The items of preventive maintenance are a result of a known or suspected mechanical difficulty or malfunction that occurred en route to or in a remote area;

(2) The pilot has satisfactorily completed an approved training program and is authorized in writing by the certificate holder for each item of preventive maintenance that the pilot is authorized to perform;

(3) There is no certificated mechanic available to perform preventive maintenance;

(4) The certificate holder has procedures to evaluate the accomplishment of a preventive maintenance item that requires a decision concerning the airworthiness of the rotorcraft; and

(5) The items of preventive maintenance authorized by this section are those listed in paragraph (c) of appendix A of this part.

(i) Notwithstanding the provisions of paragraph (g) of this section, in accordance with an approval issued to the holder of a certificate issued under part 135 of this chapter, a pilot of an aircraft type-certificated for 9 or fewer passenger seats, excluding any pilot seat, may perform the removal and reinstallation of approved aircraft cabin seats, approved cabin-mounted stretchers, and when no tools are required, approved cabin-mounted medical oxygen bottles, provided—

(1) The pilot has satisfactorily completed an approved training program and is authorized in writing by the certificate holder to perform each task; and

(2) The certificate holder has written procedures available to the pilot to evaluate the accomplishment of the task.

(j) A manufacturer may—

(1) Rebuild or alter any aircraft, aircraft engine, propeller, or appliance manufactured by him under a type or production certificate;

(2) Rebuild or alter any appliance or part of aircraft, aircraft engines, propellers, or appliances manufactured by him under a Technical Standard Order Authorization, an FAA-Parts Manufacturer Approval, or Product and Process Specification issued by the Administrator; and

(3) Perform any inspection required by Part 91 or Part 125 of this chapter on aircraft it manufacturers, while currently operating under a production certificate or under a currently approved production inspection system for such aircraft.

Code of Federal Regulations

[Doc. No. 1993, 29 FR 5451, Apr. 23, 1964, as amended by Amdt. 43-4, 31 FR 5249, Apr. 1, 1966; Amdt. 43-23, 47 FR 41084, Sept. 16, 1982; Amdt. 43-25, 51 FR 40702, Nov. 7, 1986; Amdt. 43-36, 61 FR 19501, May 1, 1996; Amdt. 43-37, 66 FR 21066, Apr. 27, 2001; Amdt. 43-39, 69 FR 44863, July 27, 2004]

Code of Federal Regulations

Effective Date Note: By Amdt. No. 43-43, 74 FR 53394, Oct. 16, 2009, § 43.3(j)(3) was revised, effective Apr. 14, 2010. The effective date of this revision was subsequently postponed to Apr. 16, 2011 at 75 FR 9095, Mar. 1, 2010. For the convenience of the user, the revised text is set forth as follows: § 43.3 Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations. (j) * * * (3) Perform any inspection required by part 91 or part 125 of this chapter on aircraft it manufactured under a type certificate, or currently manufactures under a production certificate. Pt. 43, App. A Appendix A to Part 43 —Major Alterations, Major Repairs, and Preventive Maintenance (a) Major alterations—(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations: (i) Wings. (ii) Tail surfaces. (iii) Fuselage. (iv) Engine mounts. (v) Control system. (vi) Landing gear. (vii) Hull or floats. (viii) Elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights. (ix) Hydraulic and electrical actuating system of components. (x) Rotor blades. (xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft. (xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems. (xiii) Changes to the wing or to fixed or movable control surfaces which affect flutter and vibration characteristics. (2) Powerplant major alterations. The following alterations of a powerplant when not listed in the engine specifications issued by the FAA, are powerplant major alterations. (i) Conversion of an aircraft engine from one approved model to another, involving any changes in compression ratio, propeller reduction gear, impeller gear ratios or the substitution of major engine parts which requires extensive rework and testing of the engine. (ii) Changes to the engine by replacing aircraft engine structural parts with parts not supplied by the original manufacturer or parts not specifically approved by the Administrator. (iii) Installation of an accessory which is not approved for the engine. (iv) Removal of accessories that are listed as required equipment on the aircraft or engine specification. (v) Installation of structural parts other than the type of parts approved for the installation. (vi) Conversions of any sort for the purpose of using fuel of a rating or grade other than that listed in the engine specifications. (3) Propeller major alterations. The following alterations of a propeller when not authorized in the propeller specifications issued by the FAA are propeller major alterations: (i) Changes in blade design. (ii) Changes in hub design. (iii) Changes in the governor or control design. (iv) Installation of a propeller governor or feathering system. (v) Installation of propeller de-icing system. (vi) Installation of parts not approved for the propeller. (4) Appliance major alterations. Alterations of the basic design not made in accordance with recommendations of the appliance manufacturer or in accordance with an FAA Airworthiness Directive are appliance major alterations. In addition, changes in the basic design of radio communication and navigation equipment approved under type certification or a Technical Standard Order that have an effect on frequency stability, noise level, sensitivity, selectivity, distortion, spurious radiation, AVC characteristics, or ability to meet environmental test conditions and other changes that have an effect on the performance of the equipment are also major alterations.

Code of Federal Regulations 982

(b) Major repairs—(1) Airframe major repairs. Repairs to the following parts of an airframe and repairs of the following types, 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 airframe major repairs. (i) Box beams. (ii) Monocoque or semimonocoque wings or control surfaces. (iii) Wing stringers or chord members. (iv) Spars. (v) Spar flanges. (vi) Members of truss-type beams. (vii) Thin sheet webs of beams. (viii) Keel and chine members of boat hulls or floats. (ix) Corrugated sheet compression members which act as flange material of wings or tail surfaces. (x) Wing main ribs and compression members. (xi) Wing or tail surface brace struts. (xii) Engine mounts. (xiii) Fuselage longerons. (xiv) Members of the side truss, horizontal truss, or bulkheads. (xv) Main seat support braces and brackets. (xvi) Landing gear brace struts. (xvii) Axles. (xviii) Wheels. (xix) Skis, and ski pedestals. (xx) Parts of the control system such as control columns, pedals, shafts, brackets, or horns. (xxi) Repairs involving the substitution of material. (xxii) The repair of damaged areas in metal or plywood stressed covering exceeding six inches in any direction. (xxiii) The repair of portions of skin sheets by making additional seams. (xxiv) The splicing of skin sheets. (xxv) The repair of three or more adjacent wing or control surface ribs or the leading edge of wings and control surfaces, between such adjacent ribs. (xxvi) Repair of fabric covering involving an area greater than that required to repair two adjacent ribs. (xxvii) Replacement of fabric on fabric covered parts such as wings, fuselages, stabilizers, and control surfaces. (xxviii) Repairing, including rebottoming, of removable or integral fuel tanks and oil tanks. (2) Powerplant major repairs. Repairs of the following parts of an engine and repairs of the following types, are powerplant major repairs: (i) Separation or disassembly of a crankcase or crankshaft of a reciprocating engine equipped with an integral supercharger. (ii) Separation or disassembly of a crankcase or crankshaft of a reciprocating engine equipped with other than spur-type propeller reduction gearing. (iii) Special repairs to structural engine parts by welding, plating, metalizing, or other methods. (3) Propeller major repairs. Repairs of the following types to a propeller are propeller major repairs: (i) Any repairs to, or straightening of steel blades. (ii) Repairing or machining of steel hubs. (iii) Shortening of blades. (iv) Retipping of wood propellers. (v) Replacement of outer laminations on fixed pitch wood propellers. (vi) Repairing elongated bolt holes in the hub of fixed pitch wood propellers. (vii) Inlay work on wood blades. (viii) Repairs to composition blades. (ix) Replacement of tip fabric. (x) Replacement of plastic covering. (xi) Repair of propeller governors. (xii) Overhaul of controllable pitch propellers. (xiii) Repairs to deep dents, cuts, scars, nicks, etc., and straightening of aluminum blades. (xiv) The repair or replacement of internal elements of blades. (4) Appliance major repairs. Repairs of the following types to appliances are appliance major repairs: (i) Calibration and repair of instruments. (ii) Calibration of radio equipment. (iii) Rewinding the field coil of an electrical accessory. (iv) Complete disassembly of complex hydraulic power valves. (v) Overhaul of pressure type carburetors, and pressure type fuel, oil and hydraulic pumps. (c) Preventive maintenance. Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations: (1) Removal, installation, and repair of landing gear tires. (2) Replacing elastic shock absorber cords on landing gear. (3) Servicing landing gear shock struts by adding oil, air, or both. (4) Servicing landing gear wheel bearings, such as cleaning and greasing. (5) Replacing defective safety wiring or cotter keys.

Code of Federal Regulations 983

(6) Lubrication not requiring disassembly other than removal of nonstructural items such as cover plates, cowlings, and fairings. (7) Making simple fabric patches not requiring rib stitching or the removal of structural parts or control surfaces. In the case of balloons, the making of small fabric repairs to envelopes (as defined in, and in accordance with, the balloon manufacturers' instructions) not requiring load tape repair or replacement. (8) Replenishing hydraulic fluid in the hydraulic reservoir. (9) Refinishing decorative coating of fuselage, balloon baskets, wings tail group surfaces (excluding balanced control surfaces), fairings, cowlings, landing gear, cabin, or cockpit interior when removal or disassembly of any primary structure or operating system is not required. (10) Applying preservative or protective material to components where no disassembly of any primary structure or operating system is involved and where such coating is not prohibited or is not contrary to good practices. (11) Repairing upholstery and decorative furnishings of the cabin, cockpit, or balloon basket interior when the repairing does not require disassembly of any primary structure or operating system or interfere with an operating system or affect the primary structure of the aircraft. (12) Making small simple repairs to fairings, nonstructural cover plates, cowlings, and small patches and reinforcements not changing the contour so as to interfere with proper air flow. (13) Replacing side windows where that work does not interfere with the structure or any operating system such as controls, electrical equipment, etc. (14) Replacing safety belts. (15) Replacing seats or seat parts with replacement parts approved for the aircraft, not involving disassembly of any primary structure or operating system. (16) Trouble shooting and repairing broken circuits in landing light wiring circuits. (17) Replacing bulbs, reflectors, and lenses of position and landing lights. (18) Replacing wheels and skis where no weight and balance computation is involved. (19) Replacing any cowling not requiring removal of the propeller or disconnection of flight controls. (20) Replacing or cleaning spark plugs and setting of spark plug gap clearance. (21) Replacing any hose connection except hydraulic connections. (22) Replacing prefabricated fuel lines. (23) Cleaning or replacing fuel and oil strainers or filter elements. (24) Replacing and servicing batteries. (25) Cleaning of balloon burner pilot and main nozzles in accordance with the balloon manufacturer's instructions. (26) Replacement or adjustment of nonstructural standard fasteners incidental to operations. (27) The interchange of balloon baskets and burners on envelopes when the basket or burner is designated as interchangeable in the balloon type certificate data and the baskets and burners are specifically designed for quick removal and installation. (28) The installations of anti-misfueling devices to reduce the diameter of fuel tank filler openings provided the specific device has been made a part of the aircraft type certificiate data by the aircraft manufacturer, the aircraft manufacturer has provided FAA-approved instructions for installation of the specific device, and installation does not involve the disassembly of the existing tank filler opening. (29) Removing, checking, and replacing magnetic chip detectors. (30) The inspection and maintenance tasks prescribed and specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder's approved special inspection and preventive maintenance program when accomplished on a primary category aircraft provided: (i) They are performed by the holder of at least a private pilot certificate issued under part 61 who is the registered owner (including co-owners) of the affected aircraft and who holds a certificate of competency for the affected aircraft (1) issued by a school approved under § 147.21(e) of this chapter; (2) issued by the holder of the production certificate for that primary category aircraft that has a special training program approved under § 21.24 of this subchapter; or (3) issued by another entity that has a course approved by the Administrator; and (ii) The inspections and maintenance tasks are performed in accordance with instructions contained by the special inspection and preventive maintenance program approved as part of the aircraft's type design or supplemental type design. (31) Removing and replacing self-contained, front instrument panel-mounted navigation and communication devices that employ tray-mounted connectors that connect the unit when the unit is installed into the instrument panel, (excluding automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)). The approved unit must be designed to be readily and repeatedly removed and replaced, and pertinent instructions must be provided. Prior to the unit's intended use, and operational check must be performed in accordance with the applicable sections of part 91 of this chapter . (32) Updating self-contained, front instrument panel-mounted Air Traffic Control (ATC) navigational software data bases (excluding those of automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)) provided no disassembly of the unit is required and pertinent instructions are provided. Prior to the unit's intended use, an operational check must be performed in accordance with applicable sections of part 91 of this chapter .

Code of Federal Regulations 984

(Secs. 313, 601 through 610, and 1102, Federal Aviation Act of 1958 as amended ( 49 U.S.C. 1354, 1421 through 1430 and 1502); ( 49 U.S.C. 106(g) (Revised Pub. L. 97-449, Jan. 21, 1983); and 14 CFR 11.45 ) [Doc. No. 1993, 29 FR 5451, Apr. 23, 1964, as amended by Amdt. 43-14, 37 FR 14291, June 19, 1972; Amdt. 43-23, 47 FR 41086, Sept. 16, 1982; Amdt. 43-24, 49 FR 44602, Nov. 7, 1984; Amdt. 43-25, 51 FR 40703, Nov. 7, 1986; Amdt. 43-27, 52 FR 17277, May 6, 1987; Amdt. 43-34, 57 FR 41369, Sept. 9, 1992; Amdt. 43-36, 61 FR 19501, May 1, 1996] Pt. 43, App. B Appendix B to Part 43 —Recording of Major Repairs and Major Alterations (a) Except as provided in paragraphs (b), (c), and (d) of this appendix, each person performing a major repair or major alteration shall— (1) Execute FAA Form 337 at least in duplicate; (2) Give a signed copy of that form to the aircraft owner; and (3) Forward a copy of that form to the FAA Aircraft Registration Branch in Oklahoma City, Oklahoma, within 48 hours after the aircraft, airframe, aircraft engine, propeller, or appliance is approved for return to service. (b) For major repairs made in accordance with a manual or specifications acceptable to the Administrator, a certificated repair station may, in place of the requirements of paragraph (a)— (1) Use the customer's work order upon which the repair is recorded; (2) Give the aircraft owner a signed copy of the work order and retain a duplicate copy for at least two years from the date of approval for return to service of the aircraft, airframe, aircraft engine, propeller, or appliance; (3) Give the aircraft owner a maintenance release signed by an authorized representative of the repair station and incorporating the following information: (i) Identity of the aircraft, airframe, aircraft engine, propeller or appliance. (ii) If an aircraft, the make, model, serial number, nationality and registration marks, and location of the repaired area. (iii) If an airframe, aircraft engine, propeller, or appliance, give the manufacturer's name, name of the part, model, and serial numbers (if any); and (4) Include the following or a similarly worded statement— “The aircraft, airframe, aircraft engine, propeller, or appliance identified above was repaired and inspected in accordance with current Regulations of the Federal Aviation Agency and is approved for return to service. Pertinent details of the repair are on file at this repair station under Order No. ___, Date Signed For signature of authorized representative) Repair station name)(Certificate No.) ____________.” (Address) (c) Except as provided in paragraph (d) of this appendix, for a major repair or major alteration made by a person authorized in § 43.17 , the person who performs the major repair or major alteration and the person authorized by § 43.17 to approve that work shall execute an FAA Form 337 at least in duplicate. A completed copy of that form shall be— (1) Given to the aircraft owner; and (2) Forwarded to the Federal Aviation Administration, Aircraft Registration Branch, AFS-750, Post Office Box 25504, Oklahoma City, OK 73125, within 48 hours after the work is inspected. (d) For extended-range fuel tanks installed within the passenger compartment or a baggage compartment, the person who performs the work and the person authorized to approve the work by § 43.7 shall execute an FAA Form 337 in at least triplicate. A completed copy of that form shall be— (1) Placed on board the aircraft as specified in § 91.417 of this chapter; (2) Given to the aircraft owner; and (3) Forwarded to the Federal Aviation Administration, Aircraft Registration Branch, AFS-751, Post Office Box 25724, Oklahoma City, OK 73125, within 48 hours after the work is inspected. (Secs. 101, 610, 72 Stat. 737, 780, 49 U.S.C. 1301, 1430 ) [Doc. No. 1993, 29 FR 5451, Apr. 23, 1964, as amended by Amdt. 43-10, 33 FR 15989, Oct. 31, 1968; Amdt. 43-29, 52 FR 34101, Sept. 9, 1987; Amdt. 43-31, 54 FR 34330, Aug. 18, 1989; 71 FR 58495, Oct. 4, 2006; Amdt. 43-41, 72 FR 53680, Sept. 20, 2007]

Code of Federal Regulations 985

Appendix C to Part 43 [Reserved]
Pt. 43, App. D Appendix D to Part 43 —Scope and Detail of Items (as Applicable to the Particular Aircraft) To Be Included in Annual and 100-Hour Inspections (a) Each person performing an annual or 100-hour inspection shall, before that inspection, remove or open all necessary inspection plates, access doors, fairing, and cowling. He shall thoroughly clean the aircraft and aircraft engine. (b) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the fuselage and hull group: (1) Fabric and skin—for deterioration, distortion, other evidence of failure, and defective or insecure attachment of fittings. (2) Systems and components—for improper installation, apparent defects, and unsatisfactory operation. (3) Envelope, gas bags, ballast tanks, and related parts—for poor condition. (c) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the cabin and cockpit group: (1) Generally—for uncleanliness and loose equipment that might foul the controls. (2) Seats and safety belts—for poor condition and apparent defects. (3) Windows and windshields—for deterioration and breakage. (4) Instruments—for poor condition, mounting, marking, and (where practicable) improper operation. (5) Flight and engine controls—for improper installation and improper operation. (6) Batteries—for improper installation and improper charge. (7) All systems—for improper installation, poor general condition, apparent and obvious defects, and insecurity of attachment. (d) Each person performing an annual or 100-hour inspection shall inspect (where applicable) components of the engine and nacelle group as follows: (1) Engine section—for visual evidence of excessive oil, fuel, or hydraulic leaks, and sources of such leaks. (2) Studs and nuts—for improper torquing and obvious defects. (3) Internal engine—for cylinder compression and for metal particles or foreign matter on screens and sump drain plugs. If there is weak cylinder compression, for improper internal condition and improper internal tolerances. (4) Engine mount—for cracks, looseness of mounting, and looseness of engine to mount. (5) Flexible vibration dampeners—for poor condition and deterioration. (6) Engine controls—for defects, improper travel, and improper safetying. (7) Lines, hoses, and clamps—for leaks, improper condition and looseness. (8) Exhaust stacks—for cracks, defects, and improper attachment. (9) Accessories—for apparent defects in security of mounting. (10) All systems—for improper installation, poor general condition, defects, and insecure attachment. (11) Cowling—for cracks, and defects. (e) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the landing gear group: (1) All units—for poor condition and insecurity of attachment. (2) Shock absorbing devices—for improper oleo fluid level. (3) Linkages, trusses, and members—for undue or excessive wear fatigue, and distortion. (4) Retracting and locking mechanism—for improper operation. (5) Hydraulic lines—for leakage. (6) Electrical system—for chafing and improper operation of switches. (7) Wheels—for cracks, defects, and condition of bearings. (8) Tires—for wear and cuts. (9) Brakes—for improper adjustment. (10) Floats and skis—for insecure attachment and obvious or apparent defects. (f) Each person performing an annual or 100-hour inspection shall inspect (where applicable) all components of the wing and center section assembly for poor general condition, fabric or skin deterioration, distortion, evidence of failure, and insecurity of attachment. (g) Each person performing an annual or 100-hour inspection shall inspect (where applicable) all components and systems that make up the complete empennage assembly for poor general condition, fabric or skin deterioration, distortion, evidence of failure, insecure attachment, improper component installation, and improper component operation. (h) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the propeller group: (1) Propeller assembly—for cracks, nicks, binds, and oil leakage. (2) Bolts—for improper torquing and lack of safetying. (3) Anti-icing devices—for improper operations and obvious defects. (4) Control mechanisms—for improper operation, insecure mounting, and restricted travel. (i) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the radio group:

Code of Federal Regulations 986

(1) Radio and electronic equipment—for improper installation and insecure mounting. (2) Wiring and conduits—for improper routing, insecure mounting, and obvious defects. (3) Bonding and shielding—for improper installation and poor condition. (4) Antenna including trailing antenna—for poor condition, insecure mounting, and improper operation. (j) Each person performing an annual or 100-hour inspection shall inspect (where applicable) each installed miscellaneous item that is not otherwise covered by this listing for improper installation and improper operation. Pt. 43, App. E Appendix E to Part 43 —Altimeter System Test and Inspection Each person performing the altimeter system tests and inspections required by § 91.411 shall comply with the following: (a) Static pressure system: (1) Ensure freedom from entrapped moisture and restrictions. (2) Determine that leakage is within the tolerances established in § 23.1325 or § 25.1325 , whichever is applicable. (3) Determine that the static port heater, if installed, is operative. (4) Ensure that no alterations or deformations of the airframe surface have been made that would affect the relationship between air pressure in the static pressure system and true ambient static air pressure for any flight condition. (b) Altimeter: (1) Test by an appropriately rated repair facility in accordance with the following subparagraphs. Unless otherwise specified, each test for performance may be conducted with the instrument subjected to vibration. When tests are conducted with the temperature substantially different from ambient temperature of approximately 25 degrees C., allowance shall be made for the variation from the specified condition. (i) Scale error. With the barometric pressure scale at 29.92 inches of mercury, the altimeter shall be subjected successively to pressures corresponding to the altitude specified in Table I up to the maximum normally expected operating altitude of the airplane in which the altimeter is to be installed. The reduction in pressure shall be made at a rate not in excess of 20,000 feet per minute to within approximately 2,000 feet of the test point. The test point shall be approached at a rate compatible with the test equipment. The altimeter shall be kept at the pressure corresponding to each test point for at least 1 minute, but not more than 10 minutes, before a reading is taken. The error at all test points must not exceed the tolerances specified in Table I. (ii) Hysteresis. The hysteresis test shall begin not more than 15 minutes after the altimeter's initial exposure to the pressure corresponding to the upper limit of the scale error test prescribed in subparagraph (i); and while the altimeter is at this pressure, the hysteresis test shall commence. Pressure shall be increased at a rate simulating a descent in altitude at the rate of 5,000 to 20,000 feet per minute until within 3,000 feet of the first test point (50 percent of maximum altitude). The test point shall then be approached at a rate of approximately 3,000 feet per minute. The altimeter shall be kept at this pressure for at least 5 minutes, but not more than 15 minutes, before the test reading is taken. After the reading has been taken, the pressure shall be increased further, in the same manner as before, until the pressure corresponding to the second test point (40 percent of maximum altitude) is reached. The altimeter shall be kept at this pressure for at least 1 minute, but not more than 10 minutes, before the test reading is taken. After the reading has been taken, the pressure shall be increased further, in the same manner as before, until atmospheric pressure is reached. The reading of the altimeter at either of the two test points shall not differ by more than the tolerance specified in Table II from the reading of the altimeter for the corresponding altitude recorded during the scale error test prescribed in paragraph (b)(i). (iii) After effect. Not more than 5 minutes after the completion of the hysteresis test prescribed in paragraph (b)(ii), the reading of the altimeter (corrected for any change in atmospheric pressure) shall not differ from the original atmospheric pressure reading by more than the tolerance specified in Table II. (iv) Friction. The altimeter shall be subjected to a steady rate of decrease of pressure approximating 750 feet per minute. At each altitude listed in Table III, the change in reading of the pointers after vibration shall not exceed the corresponding tolerance listed in Table III. (v) Case leak. The leakage of the altimeter case, when the pressure within it corresponds to an altitude of 18,000 feet, shall not change the altimeter reading by more than the tolerance shown in Table II during an interval of 1 minute. (vi) Barometric scale error. At constant atmospheric pressure, the barometric pressure scale shall be set at each of the pressures (falling within its range of adjustment) that are listed in Table IV, and shall cause the pointer to indicate the equivalent altitude difference shown in Table IV with a tolerance of 25 feet. (2) Altimeters which are the air data computer type with associated computing systems, or which incorporate air data correction internally, may be tested in a manner and to specifications developed by the manufacturer which are acceptable to the Administrator.

Code of Federal Regulations 987

(c) Automatic Pressure Altitude Reporting Equipment and ATC Transponder System Integration Test. The test must be conducted by an appropriately rated person under the conditions specified in paragraph (a). Measure the automatic pressure altitude at the output of the installed ATC transponder when interrogated on Mode C at a sufficient number of test points to ensure that the altitude reporting equipment, altimeters, and ATC transponders perform their intended functions as installed in the aircraft. The difference between the automatic reporting output and the altitude displayed at the altimeter shall not exceed 125 feet. (d) Records: Comply with the provisions of § 43.9 of this chapter as to content, form, and disposition of the records. The person performing the altimeter tests shall record on the altimeter the date and maximum altitude to which the altimeter has been tested and the persons approving the airplane for return to service shall enter that data in the airplane log or other permanent record. Table I

Altitude	Equivalent pressure (inches of mercury)	Tolerance ±(feet)
−1,000	31.018	20
0	29.921	20
500	29.385	20
1,000	28.856	20
1,500	28.335	25
2,000	27.821	30
3,000	26.817	30
4,000	25.842	35
6,000	23.978	40
8,000	22.225	60
10,000	20.577	80
12,000	19.029	90
14,000	17.577	100
16,000	16.216	110
18,000	14.942	120
20,000	13.750	130
22,000	12.636	140
25,000	11.104	155
30,000	8.885	180
35,000	7.041	205
40,000	5.538	230
45,000	4.355	255
50,000	3.425	280

Table II—Test Tolerances

Test	Tolerance (feet)
Case Leak Test	±100
Hysteresis Test:
First Test Point (50 percent of maximum altitude)	75
Second Test Point (40 percent of maximum altitude)	75
After Effect Test	30

Table III—Friction

Tips

Altitude (feet)	Tolerance (feet)
1,000	±70
2,000	70
3,000	70
5,000	70
10,000	80
15,000	90
20,000	100