AC 21.17-4 Appendix A performance levels, operational limits, and at any other conditions or power settings, including energy regeneration, that are required to verify the limit capabilities of the engine.
PL.3388 Temperature limit.
The engine design must demonstrate its capability to endure operation at its temperature limits plus an acceptable margin. The applicant must quantify and justify the margin to the Administrator. The demonstration must be repeated for all declared duty cycles and ratings, and operating environments, which would impact temperature limits.
PL.3389 Operation demonstration.
The engine design must demonstrate safe operating characteristics, including but not limited to starting, acceleration, power cycling, overspeeding, and power/thrust response in accordance with PL.3373 throughout the approved flight envelope and operating range. The declared engine operational characteristics must account for installation loads and effects.
PL.3390 Durability demonstration.
The engine must be subjected to a durability demonstration to show that each part of the engine has been designed and constructed to minimize any unsafe condition of the system between overhaul periods or between engine replacement intervals if the overhaul is not defined. This test must simulate the conditions in which the engine is expected to operate in service, including typical start-stop cycles, to establish when the initial maintenance is required.
PL.3391 System and component tests.
The applicant must show that systems and components that cannot be adequately substantiated in accordance with the endurance demonstration or other demonstrations will perform their intended functions in all declared environmental and operating conditions.
PL.3392 Rotor locking demonstration.
If shaft rotation is prevented by locking the rotor(s), the engine must demonstrate:
(a) Reliable rotor locking performance;
(b) Reliable rotor unlocking performance; and
(c) That no hazardous engine effects, as specified in PL.3375(g)(2), will occur.
PL.3393 Teardown inspection.
(a) After the endurance and durability demonstrations have been completed, the engine must be completely disassembled. Each engine component and lubricant must be eligible for continued operation in accordance with the information submitted for showing compliance with PL.1529.
(b) Each engine component having an adjustment setting and a functioning characteristic that can be established independent of installation on or in the engine must retain each setting and functioning characteristic within the established and recorded limits at the beginning of the endurance and durability demonstrations.
(c) If a teardown cannot be performed for all engine components in a non-destructive manner, then the inspection or replacement intervals for these components and lubricants must be:
(1) Established based on the endurance and durability demonstrations; and A-40
AC 21 .17-4 Appendix A
(2) Documented in the ICA in accordance with PL.1529.
PL.3394 Containment.
The engine must be designed and constructed to protect against likely hazards from rotating components as follows:
(a) The design of the case surrounding rotating components must provide for the containment of the rotating components in the event of failure, unless the applicant shows that the margin to rotor burst precludes the possibility of a rotor burst.
(b) If the margin to burst shows that the case must have containment features in the event of failure, then the case must provide for the containment of the failed rotating components. The applicant must define by test, validated analysis, or a combination thereof, and document in accordance with the requirements in P L.3305, the energy level, trajectory, and size of fragments released from damage caused by the main rotor failure, and that pass forward or aft of the surrounding case.
PL.3395 Engine-propeller systems tests.
(a) An engine that is intended to be equipped with a propeller must be fitted for the demonstrations in PL.3387, PL.3390, PL.3383, and PL.3389 with a representative propeller. If the engine-propeller system can be tilted from vertical to horizontal operation and vice versa, the transitions must be included.
(b) For variable pitch propellers, the applicant must conduct functional demonstrations including feathering, negative torque, negative thrust, and reverse thrust operations, as applicable, with a representative propeller.
(c) The demonstrations must be accomplished in accordance with paragraph (a) and (b) of this section or otherwise performed in a manner acceptable to the Administrator.
PL.3399 General conduct of tests.
(a) Maintenance of the engine may be made during the tests in accordance with the service and maintenance instructions submitted in compliance with PL.1529.
(b) The applicant must subject the engine or its parts to any additional tests that the Administrator finds necessary if—
(1) The frequency of engine service is excessive;
(2) The number of stops due to engine malfunction is excessive;
(3) Major engine repairs are needed; or
(4) Replacement of an engine part is found necessary during the tests or due to the teardown inspection findings.
(c) Upon completion of all demonstrations and testing specified in these airworthiness criteria, the engine and its components must be—
(1) Within serviceable limits;
(2) Safe for continued operation; and
(3) Capable of operating at declared ratings while remaining within limits.
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AC 21.17-4 Appendix A SUBPART J—PROPELLER and ENGINE-DRIVEN LIFT DEVICES PL.3503 Instructions for propeller installation and operation.
The applicant must provide instructions that are approved by the Administrator. Those approved instructions must contain:
(a) Instructions for installing the propeller, which:
(1) Include a description of the operational modes of the propeller control system and functional interface of the control system with the aircraft and engine systems;
(2) Specify the physical and functional interfaces with the aircraft, aircraft equipment and engine;
(3) Define the limiting conditions on the interfaces from paragraph (a)(2) of this section;
(4) List the limitations established under PL.3505;
(5) Define the hydraulic fluids approved for use with the propeller, including grade and specification, related operating pressure, and filtration levels; and
(6) State the assumptions made to comply with the requirements of these airworthiness criteria.
(b) Instructions for operating the propeller which must specify all procedures necessary for operating the propeller within the limitations of the propeller type design.
PL.3505 Propeller ratings and operating limitations.
Propeller ratings and operating limitations must be established by the applicant and approved by the Administrator, including ratings and limitations based on the operating conditions and information specified in this subpart, as applicable, and any other information found necessary for safe operation of the propeller.
PL.3507 Features and characteristics.
(a) The propeller may not have features or characteristics, revealed by any test or analysis or known to the applicant, that make it unsafe for the uses for which certification is requested.
(b) If a failure occurs during a certification test, the applicant must determine the cause and assess the effect on the airworthiness of the propeller. The applicant must make changes to the design and conduct additional tests that the Administrator finds necessary to establish the airworthiness of the propeller.
PL.3515 Safety analysis.
(a) The applicant must:
(1) Analyze the propeller system to assess the likely consequences of all failures that can reasonably be expected to occur. This analysis will take into account, if applicable:
(i) The propeller system when installed on the aircraft. When the analysis depends on representative components, assumed interfaces, or assumed installed conditions, the assumptions must be stated in the analysis.
(ii) Consequential secondary failures and dormant failures.
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AC 21.17-4 Appendix A
(iii) Multiple failures referred to in paragraph (d) of this section, or that result in the hazardous propeller effects defined in paragraph (g)(1) of this section.
(2) Summarize those failures that could result in major propeller effects or hazardous propeller effects defined in paragraph (g) of this section, and estimate the probability of occurrence of those effects.
(3) Show that hazardous propeller effects are not predicted to occur at a rate that exceeds 10-7 per propeller flight hour. Because the estimated probability for individual failures may be insufficiently precise to enable the applicant to assess the total rate for hazardous propeller effects, compliance may be shown by demonstrating that the probability of a hazardous propeller effect arising from an individual failure can be predicted to be not greater than 10-8 per propeller flight hour. In dealing with probabilities of this low order of magnitude, absolute proof is not possible, and reliance must be placed on engineering judgment and previous experience, combined with sound design and test philosophies.
(b) If significant doubt exists as to the effects of failures or likely combination of failures, the Administrator may require assumptions used in the analysis to be verified by test.
(c) The primary failures of certain single propeller elements (for example, blades) cannot be sensibly estimated in numerical terms. If the failure of such elements is likely to result in hazardous propeller effects, those elements must be identified as propeller critical parts. For propeller critical parts, the applicant must meet the prescribed integrity specifications of PL.3516. These instances must be stated in the safety analysis.
(d) If reliance is placed on a safety system to prevent a failure progressing to hazardous propeller effects, the possibility of a safety system failure, in combination with a basic propeller failure, must be included in the analysis. Such a safety system may include safety devices, instrumentation, early warning devices, maintenance checks, and other similar equipment or procedures.
(e) If the safety analysis depends on one or more of the following items, those items must be identified in the analysis and appropriately substantiated.
(1) Maintenance actions being carried out at stated intervals. This includes verifying that items that could fail in a latent manner are functioning properly. When necessary to prevent hazardous propeller effects, these maintenance act ions and intervals must be published in the ICA required under PL.1529. Additionally, if errors in maintenance of the propeller system could lead to hazardous propeller effects, the appropriate maintenance procedures must be included in the relevant propeller manuals.
(2) Verification of the satisfactory functioning of safety or other devices at pre-flight or other stated periods. The details of this satisfactory functioning must be published in the appropriate manual.
(3) The provision of specific instrumentation not otherwise required. Such instrumentation must be published in the appropriate documentation.
(4) A fatigue assessment.
(f) If applicable, the safety analysis must include, but not be limited to, assessment of indicating equipment, manual and automatic controls, governors and propeller-control systems, synchrophasers, synchronizers, and propeller thrust reversal systems.
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AC 21 .17-4 Appendix A
(g) Unless otherwise approved by the Administrator and stated in the safety analysis, the following failure definitions apply to compliance with these airworthiness criteria.
(1) The following are regarded as hazardous propeller effects:
(i) The development of excessive drag.
(ii) A significant thrust in the opposite direction to that commanded by the pilot.
(iii) The release of the propeller or any major portion of the propeller.
(iv) A failure that results in excessive unbalance.
(2) The following are regarded as major propeller effects for variable-pitch propellers:
(i) An inability to feather the propeller for feathering propellers.
(ii) An inability to change propeller pitch when commanded.
(iii) A significant uncommanded change in pitch.
(iv) A significant uncontrollable torque or speed fluctuation.
PL.3516 Propeller critical parts.
The integrity of each propeller critical part identified by the safety analysis required by PL.3515 must be established by:
(a) A defined engineering process for ensuring the integrity of the propeller critical part throughout its service life,
(b) A defined manufacturing process that identifies the requirements to consistently produce the propeller critical part as required by the engineering process, and
(c) A defined service-management process that identifies the co ntinued airworthiness requirements of the propeller critical part as required by the engineering process.
PL.3517 Materials and manufacturing methods.
(a) The suitability and durability of materials used in the propeller must:
(1) Be established on the basis of experience, tests, or both.
(2) Account for environmental conditions expected in service.
(b) All materials and manufacturing methods must conform to specifications acceptable to the Administrator.
(c) The design values of properties of materials must be suitably related to the most adverse properties stated in the material specification for applicable conditions expected in service.
PL.3519 Durability.
Each part of the propeller must be designed and constructed to minimize the development of any unsafe condition of the propeller between overhaul periods.
PL.3521 Variable- and reversible-pitch propellers.
(a) No single failure or malfunction in the propeller system will result in unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of any intended travel below the in-flight low-pitch position must be documented by the applicant in the appropriate manuals. Failure of structural elements need not be considered if the occurrence of such a failure is shown to be extremely remote under PL.3515.
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AC 21.17-4 Appendix A
(b) For propellers incorporating a method to select blade pitch below the in-flight low-pitch position, provisions must be made to sense and indicate to the flightcrew that the propeller blades are below that position by an amount defined in the installation instructions. The method for sensing and indicating the propeller blade pitch position must be such that its failure does not affect the control of the propeller.
PL.3522 Feathering propellers.
(a) Feathering propellers are intended to feather from all flight conditions, taking into account expected wear and leakage. Any feathering and unfeathering limitations must be documented in the appropriate manuals.
(b) Propeller pitch control systems that use engine oil to feather must incorporate a method to allow the propeller to feather if the engine oil system fails.
(c) Feathering propellers must be designed to be capable of unfeathering after the propeller system has stabilized to the minimum declared outside air temperature.
PL.3523 Propeller control system.
The requirements of this section apply to any system or component that controls, limits, or monitors propeller functions.
(a) The propeller control system must be designed, constructed and validated to show that:
(1) The propeller control system, operating in normal and alternative operating modes and in transition between operating modes, performs the functions defined by the applicant throughout the approved operating conditions and approved flight envelope.
(2) The propeller control system functionality is not adversely affected by the declared environmental conditions, including temperature, electromagnetic interference (EMI), high intensity radiated fields (HIRF), and lightning. The environmental limits to which the system has been satisfactorily validated must be documented in the appropriate propeller manuals.
(3) A method is provided to indicate that an operating mode change has occurred if flightcrew action is required. In such an event, operating instructions must be provided in the appropriate manuals.
(b) The propeller control system must be designed and constructed so that, in addition to compliance with PL.3515:
(1) No single failure results in a hazardous propeller effect;
(2) Local events in the intended aircraft installation will not result in hazardous propeller effects;
(3) The loss of normal propeller pitch control does not cause a hazardous propeller effect under the intended operating conditions; and
(4) The failure or corruption of data or signals shared across propellers does not cause a hazardous propeller effect.
(c) Electronic propeller-control-system embedded software must be designed and implemented by a method approved by the Administrator that is consistent with the criticality of the performed functions and that minimizes the existence of software errors.
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AC 21 .17-4 Appendix A
(d) The propeller control system must be designed and constructed so that the failure or corruption of aircraft-supplied data does not result in hazardous propeller effects.
(e) The propeller control system must be designed and constructed so that the loss, interruption, or abnormal characteristic of aircraft-supplied electrical power does not result in hazardous propeller effects. The power quality requirements must be described in the appropriate manuals.
PL.3524 Strength.
(a) The maximum stresses developed in the propeller may not exceed values acceptable to the Administrator considering the particular form of construction and the most severe operating conditions.
(b) Engine-driven lift devices must also comply with all applicable design load conditions and safety factors defined in subpart C.
PL.3533 General.
(a) Each applicant must furnish test article(s) and suitable testing facilities, including equipment and competent personnel, and conduct the required tests in accordance with 14 CFR part 21.
(b) All automatic controls and safety systems must be in operation unless it is accepted by the Administrator as impossible or not required because of the nature of the test. If needed for substantiation, the applicant may test a different propeller configuration if this does not constitute a less severe test.
(c) Any systems or components that cannot be adequately substantiated by the applicant to the requirements of these airworthiness criteria are required to undergo additional tests or analysis to demonstrate that the systems or components are able to perform their intended functions in all declared environmental and operating conditions.
PL.3534 Inspections, adjustments, and repairs.
(a) Before and after conducting the tests prescribed in this subpart, the test article must be subjected to an inspection, and a record must be made of all the relevant parameters, calibrations and settings.
(b) During all tests, only servicing and minor repairs are permitted. If major repairs or part replacement is required, the Administrator must approve the repair or part replacement prior to implementation and may require additional testing. Any unscheduled repair or action on the test article must be recorded and reported.
PL.3535 Centrifugal load tests.
The applicant must demonstrate that a propeller complies with paragraphs (a), (b) and (c) of this section without evidence of failure, malfunction, or permanent deformation that would result in a major or hazardous propeller effect. When the propeller could be sensitive to environmental degradation in service, this must be considered.
(a) The hub, blade retention system, and counterweights must be tested for a period of one hour to a load equivalent to twice the maximum centrifugal load to which the propeller would be subjected during operation at the maximum rated rotational speed.
(b) Blade features associated with transitions to the retention system (for example, a composite blade bonded to a metallic retention) must be tested either during the test of paragraph (a) of this A-46
AC 21.17-4 Appendix A section or in a separate component test for a period of one hour to a load equivalent to twice the maximum centrifugal load to which the propeller would be subjected during operation at the maximum rated rotational speed.
(c) Components used with or attached to the propeller (for example, spinners, de-icing equipment, and blade erosion shields) must be subjected to a load equivalent to 159 percent of the maximum centrifugal load to which the component would be subjected during operation at the maximum rated rotational speed. This must be performed by either:
(1) Testing at the required load for a period of 30 minutes; or
(2) Analysis based on test.
PL.3536 Bird impact.
The applicant must demonstrate, by tests or analysis based on tests or experience on similar designs, that the propeller can withstand the impact of a 4-pound bird at the critical location(s) and critical flight condition(s) of the intended aircraft application without causing a major or hazardous propeller effect.
PL.3537 Fatigue limits and evaluation.
(a) Fatigue limits must be established by tests, or analysis based on tests, for propeller:
(1) Hubs.
(2) Blades.
(3) Blade retention components.
(4) Components which are affected by fatigue loads and which are shown under PL.3515 to have a fatigue failure mode leading to hazardous propeller effects.
(b) The fatigue limits must take into account:
(1) All known and reasonably foreseeable vibration and cyclic load patterns that are expected in service; and
(2) Expected service deterioration, variations in material properties, manufacturing variations, and environmental effects.
(c) A fatigue evaluation of the propeller must be conducted to show that hazardous propeller effects due to fatigue will be avoided throughout the intended operational life of the propeller on the intended aircraft by complying with PL.2400(c) of these airworthiness criteria.
(d) Engine-driven lift devices must also comply with fatigue and damage tolerance evaluation defined in subpart C.
(e) Elastomeric components of engine-driven lift devices must show required dynamic performance for fatigue and damage tolerance defined in subpart C.
PL.3538 Lightning strike.
The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has been qualified must be documented in the appropriate manuals.
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AC 21 .17-4 Appendix A PL.3539 Endurance test.
Endurance tests on the propeller system must be made on a representative engine in accordance with paragraph (a) or (b) of this section, as applicable, without evidence of failure or malfunction.
(a) Fixed-pitch and ground adjustable-pitch propellers must be subjected to one of the following tests:
(1) A 50-hour flight test in level flight or in climb. The propeller must be operated at takeoff power and rated rotational speed during at least five hours of this flight test, and at not less than 90 percent of the rated rotational speed for the remainder of the 50 hours.
(2) A 50-hour ground test at takeoff power and rated rotational speed.
(b) Variable-pitch propellers and all engine-driven lift devices must be subjected to one of the following tests:
(1) A 110-hour endurance test that must include the following conditions:
(i) Five hours at takeoff power and rotational speed and thirty 10-minute cycles composed of:
(A) Acceleration from idle, (B) Five minutes at takeoff power and rotational speed, (C) Deceleration, and (D) Five minutes at idle.
(ii) Fifty hours at maximum continuous power and rotational speed,
(iii) Fifty hours, consisting of ten 5-hour cycles composed of:
(A) Five accelerations and decelerations between idle and takeoff power and rotational speed, (B) Four and one half hours at approximately even incremental conditions from idle up to, but not including, maximum continuous power and rotational speed, and (C) Thirty minutes at idle.
(2) The operation of the propeller throughout the engine endurance tests prescribed in these airworthiness criteria.
(c) For propellers having higher ratings or rotational speeds than takeoff power and rated rotational speed, those ratings and speeds must be used in the tests required by paragraph (a) or
(b) of this section.
(d) If a propeller can be tilted from vertical to horizontal operation and vice versa, the transitions must be performed as part of the tests required by paragraph (a) or (b) of this section.
PL.3540 Functional test.
The variable-pitch propeller system must be subjected to the applicable functional tests of this section. The same propeller system used in the endurance test of PL.3539 must be used in the functional tests and must be driven by a representative engine on a test stand or on the aircraft.
The propeller must complete these tests without evidence of failure or malfunction. This test may be combined with the endurance test for accumulation of cycles.
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AC 21.17-4 Appendix A
(a) Governing and reversible-pitch propellers. Fifteen hundred complete cycles must be made across the range of forward pitch and rotational speed. In addition, 200 complete cycles of control must be made from lowest normal pitch to maximum reverse pitch. During each cycle, the propeller must run for 30 seconds at the maximum power and rotational speed selected by the applicant for maximum reverse pitch.
(b) Feathering propellers. Fifty cycles of feather and unfeather operation must be made.
PL.3541 Overspeed and overtorque.
(a) When the applicant seeks approval of a transient maximum propeller overspeed, the applicant must demonstrate that the propeller is capable of further operation without maintenance action at the maximum propeller overspeed condition. This may be accomplished by:
(1) Performance of 20 runs, each of 30 seconds duration, at the maximum propeller overspeed condition; or
(2) Analysis based on test or service experience.
(b) When the applicant seeks approval of a transient maximum propeller overtorque, the applicant must demonstrate that the propeller is capable of further operation without maintenance action at the maximum propeller overtorque condition. This may be accomplished by performance of 20 runs, each of 30 seconds duration, at the maximum propeller overtorque condition.
PL.3542 Components of the propeller control system.
The applicant must demonstrate by tests, analysis based on tests, or service experience on similar components, that each propeller blade pitch control system component, including governors, pitch change assem blies, pitch locks, mechanical stops, and feathering system components, can withstand cyclic operation that simulates the normal load and pitch change travel to which the component would be subjected during the initially declared overhaul period or during a minimum of 1,000 hours of typical operation in service.
PL.3543 Propeller hydraulic components.
Applicants must show by test, validated analysis, or both, that propeller components that contain hydraulic pressure and whose structural failure or leakage from a structural failure could cause a hazardous propeller effect demonstrate structural integrity by:
(a) A proof pressure test to 1.5 times the maximum operating pressure for one minute without permanent deformation or leakage that would prevent performance of the intended function.
(b) A burst pressure test to 2.0 times the maximum operating pressure for one minute without failure. Leakage is permitted and seals may be excluded from the test.
SUBPART K—INSTRUCTIONS FOR CONTINUED AIRWORTHINESS PL.4101 General.
(a) This subpart specifies requirements for the preparation of Instructions for Continued Airworthiness as required by PL.1529.
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(b) The Instructions for Continued Airworthiness for each aircraft must include the Instructions for Continued Airworthiness for each engine and propeller (hereinafter designated “products”), for each appliance required by 14 CFR chapter I, and any required information relating to the interface of those appliances and products with the aircraft. If Instructions for Continued Airworthiness are not supplied by the manufacturer of an appliance or product installed in the aircraft, the Instructions for Continued Airworthiness for the aircraft must include the information essential to the continued airworthiness of the aircraft.
(c) The applicant must submit to the FAA a program to show how changes to the Instructions for Continued Airworthiness made by the applicant or by the manufacturers of products and appliances installed in the aircraft w ill be distributed.
PL.4102 Format.
(a) The Instructions for Continued Airworthiness must be in the form of a manual or manuals as appropriate for the quantity of data to be provided.
(b) The format of the manual or manuals must provide for a practical arrangement.
PL.4103 Content.
The contents of the manual or manuals must be prepared in the English language. The Instructions for Continued Airworthiness must contain the following manuals or sections and information:
(a) Aircraft maintenance manual or section.
(1) Introduction information that includes an explanation of the aircraft's features and data to the extent necessary for maintenance or preventive maintenance.
(2) A description of the aircraft and its systems and installations including its engines, propellers, and appliances.
(3) Basic control and operation information describing how the aircraft components and systems are controlled and how they operate, including any special procedures and limitations that apply.
(4) Servicing information that covers details regarding servicing points, capacities of tanks, reservoirs, types of fluids to be used, pressures applicable to the various systems, location of access panels for inspection and servicing, locations of lubrication points, lubricants to be used, equipment required for servicing, tow instructions and limitations, mooring, jacking, and leveling information.
(b) Maintenance Instructions.
(1) Scheduling information for each part of the aircraft and its engines, auxiliary power units, propellers, accessories, instruments, and equipment that provides the recommended periods at which they should be cleaned, inspected, adjusted, tested, and lubricated, and the degree of inspection, the applicable wear tolerances, and work recommended at these periods. However, the applicant may refer to an accessory, instrument, or equipment manufacturer as the source of this information if the applicant shows that the item has an exceptionally high degree of complexity requiring specialized maintenance techniques, test equipment, or expertise. The recommended overhaul periods and necessary cross reference to the Airworthiness Limitations section of the manual must also be included. In addition, the applicant must include an inspection A-50
AC 21 .17-4 Appendix A program that includes the frequency and extent of the inspections necessary to provide for the continued airworthiness of the aircraft.
(2) Troubleshooting information describing probable malfunctions, how to recognize those malfunctions, and the remedial action for those malfunctions.
(3) Information describing the order and method of removing and replacing products and parts with any necessary precautions to be taken.
(4) Other general procedural instructions including procedures for system testing during ground running, symmetry checks, weighing and determining the center of gravity, lifting and shoring, and storage limitations.
(c) Diagrams of structural access plates and information needed to gain access for inspections when access plates are not provided.
(d) Details for the application of special inspection techniques including radiographic and ultrasonic testing where such processes are specified by the applicant.
(e) Information needed to apply protective treatments to the structure after inspection.
(f) All data relative to structural fasteners such as identification, discard recommendations, and torque values.
(g) A list of special tools needed.
PL.4104 Airworthiness limitations section.
The Instructions for Continued Airworthiness must contain a section titled Airworthiness Limitations that is segregated and clearly distinguishable from the rest of the document. This section must set forth each mandatory maintenance action required for type certification. If the Instructions for Continued Airworthiness consist of multiple documents, the section required by this paragraph must be included in the principal manual. This section must contain a legible statement in a prominent location that reads “The Airworthiness Limitations section is FAA approved and specifies maintenance required under §§ 43.16 and 91.403 of the Federal Aviation Regulations unless an alternative program has been FAA approved.”
SUBPART L—INSTRUCTIONS FOR CONTINUED AIRWORTHINESS (ELECTRIC
ENGINE) PL.4301 General.
(a) This subpart specifies requirements for the preparation of ICA for the engines as required by PL.1529.
(b) The ICA for the engine must include the ICA for all engine parts.
(c) The applicant must submit to the FAA a program to show how the applicant’s changes to the ICA will be distributed, if applicable.
PL.4302 Format.
(a) The Instructions for Continued Airworthiness must be in the form of a manual or manuals as appropriate for the quantity of data to be provided.
(b) The format of the manual or manuals must provide for a practical arrangement.
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