other conditions or limitations prescribed by the regulations in this subchapter.

(c) The applicable provisions of this part recorded by the Administrator in accordance with § 14.12 shall be considered as incorporated in the type certificate as though set forth in full.

§ 14.14 Data required. (a) The applicant for a type certificate shall submit to the Administrator such descriptive data, test reports, and computations as are necessary to demonstrate that the propeller complies with the requirements of this part.

(b) The descriptive data required in paragraph (a) of this section shall be known as the type design and shall consist of such drawings and specifications as are necessary to disclose the configuration of the propeller and all the design features covered in the requirements of this part, such information on dimensions, materials, and processes as is necessary to define the structural strength of the propeller, and such other data as are necessary to permit by comparison the determination of the airworthiness of subsequent propellers of the same type.

§ 14.14-1 Type design data1 (CAA policies which apply to § 14.14). The data specified in paragraphs (a) through (i) of this section constitute the type design data which should be submitted in complying with § 14.14.2

(a) Parts list. No parts list need be submitted for fixed-pitch propellers. For all other type propellers, two copies of the parts list should be submitted, one copy of which, upon certification of the propeller, will be sealed and returned to the manufacturer.

(b) Drawings. (1) For fixed-pitch propellers, two sets of drawings should be submitted, one set of which will be sealed and returned to the manufacturer upon certification of the propeller.

1 Vibration stress data is not acceptable for determining the airworthiness of a propeller with respect to power and r. p. m. ratings since vibratory stresses bear no relationship to the steady stresses present during operating conditions.

2 The initial request for approval of a propeller should be accompanied by at least the drawings specified in § 14.14-1 (b) (3) (i), (vi), and (viii), stress analyses as discussed in § 14.14-1 (f) where applicable, and the proposed test program as specified in

§ 14.16-1.

(2) Only one set of drawings for propellers other than the fixed-pitch type should be submitted by the manufacturer.

(3) The following drawings should be submitted. Other drawings in lieu of those listed are acceptable provided they disclose the same information.

(i) Complete propeller assembly.
(ii) Hub assembly.

(iii) Hub.

(iv) Blade retention structural parts. (v) Blade assembly.

(vi) Blade design (if not disclosed in the blade assembly drawing).

(vii) Pitch control assemblies (if not disclosed in the propeller or hub assembly drawings).

(viii) Schematic pitch control diagram.

(ix) Such other drawings as the Administrator may find necessary to determine compliance with the requirements of this part.

(c) Production specifications. (1) Specifications covering all materials used in the manufacture of the propellers.

(2) Specifications covering all processes used in the manufacture of the propellers.

(3) Military or SAE specifications need not be submitted, but should be referred to in all drawings and materials and process specifications where applicable.

(d) Type test report. The type test report, suitably identified by title and number and signed by a responsible representative of the applicant for the type certificate, should cover the items listed in this paragraph. The applicant's report number should appear on all pages of the report.

(1) Conclusions and/or recommendations for operating limitations, if any.

(2) Description of propeller, including all accessories, such as governor and synchronizer.

(3) Summary of test conditions and log. The report need not contain the complete test log.

(4) Calibration of test instruments when necessary.

takeoff and maximum continuous ratings and reduction gear ratio.

(6) Description of test setup if other than established test stand.

(7) Test irregularities, failures and forced stops due to the propeller.

(8) Description of the condition of the propeller at the teardown inspection, including the results of magnetic particle, dye penetrant, fluorescent penetrant and X-ray inspections.

(9) Changes in the propeller during testing and proposed changes as a result of testing.

(10) If the approved version of the propeller differs from the prototype (i. e., the test propeller) parts lists for both propellers should be included in the test report and appropriately identified.

(11) Photos of failed or worn parts of the test propeller. Photos of the assembled test propeller if it is unconventional or has special features. Photos of the test rig if other than established test stand.

(e) Other reports. The applicant should submit reports covering any special tests that may be required by § 14.155.

(f) Stress analysis. A stress analysis may be acceptable in lieu of type tests for a propeller which incorporates major components similar to those in an applicant's previously certificated propeller. The analysis should present a comparison of stresses in the new propeller to those in the older propeller.

(1) For a propeller which incorporates a hub similar to one previously certificated, and previously certificated blades, the analysis should include:

(i) Total bending moment and total centrifugal force which the blade imposes on the new hub and the old hub.

(2) For a propeller which incorporates blades similar to ones previously certificated, and a previously certificated hub and pitch changing mechanism, the analysis should include:

(i) Combined stresses for several stations along the blade for the new blade and the old blade.

(ii) Total centrifugal force twisting moments at representative blade angles for the new blades and the old blades to demonstrate the relative loading of the pitch change mechanism.

(iii) Total bending moment and total centrifugal force which the new blades and the old blades impose on the hub.

(g) Reversible propeller failure analysis. The failure analysis covered by § 14.103-1 should determine what types of failures or malfunctions are most likely to occur to all components of the reversing system, should disclose how such failures or malfunctions affect propeller pitch, and what design feature prevents unwanted travel of the propeller blades to a position substantially below the normal flight low pitch stop.

(h) Flight time data. Where acceptable in the type certification of a propeller, flight time data should include a copy of the flight log certified to by the person flying the aircraft, and a statement of the estimated number of hours operated both at the maximum continuous rating and at the takeoff rating. The data should also include the model designations of the aircraft, the engine, and the propeller.

(i) Referral to data previously submitted. In lieu of submitting all of the data required for a new approval, the applicant may refer to data previously submitted by him, or if he is the holder of a current right to the benefits of a previous approval or type certificate, he may refer to data previously submitted in connection with such approval or type certificate. In any case the applicant should identify the data referred to and establish that they are pertinent and equivalent to the data required for the new approval.

[Supp. 1, 21 F. R. 5219, July 13, 1956]

§ 14.14-2 Data required for military propellers (CAA policies which apply to § 14.14). In addition to data specified in § 14.14–1 (a), (b), (c), (e) and (g), the applicant should submit the data specified in either paragraph (a) or paragraph (b) of this section.

(a) A copy of the official report which forms the basis of military approval.

(b) A letter from the military which includes the following information: (1) Identification of the propeller. (2) Identification of the engine upon which the endurance test was run. (3) Duration and r. p. m. of overspeed test.

(4) Duration and rating at which the normal-rating endurance test was run.

(5) Duration and rating at which the flash performance endurance test was

run.

(6) Number of pitch change cycles accomplished.

(7) Number of feathering cycles accomplished.

(8) Number of reversing cycles accomplished.

(9) Results of teardown inspection. (10) Operating limitations if any. [Supp. 1, 21 F. R. 5219, July 13, 1956]

In

§ 14.15 Inspections and tests. spections and tests shall include all those found necessary by the Administrator to insure that the propeller complies with the applicable airworthiness requirements and conforms to the following:

(a) All materials and products are in accordance with the specifications in the type design,

(b) All parts of the propeller are constructed in accordance with the drawings in the type design,

(c) All manufacturing processes, construction, and assembly are as specified in the type design.

§ 14.16 Required tests. The tests prescribed in this part shall be conducted to establish the propeller operating limitations, as chosen by the applicant, and the reliability of the propeller to operate within those limitations. The provisions of paragraphs (a) through (c) of this section shall be applicable.

(a) The applicant shall furnish all testing facilities, including equipment and competent personnel, to conduct the prescribed tests.

(b) An authorized representative of the Administrator shall witness such of the tests as are necessary to verify the test report.

(c) The Administrator shall establish propeller operating limitations determined on the basis of the propeller operating conditions demonstrated during the tests.

§ 14.16-1 Required tests (CAA policies which apply to § 14.16). The applicant should submit for approval his proposed type test program. The data submitted should include:

(a) How each test will be conducted. (b) Identification of propeller and accessories being tested.

(c) Identification of engine used.

(d) Location of tests and teardown inspection.

[Supp. 1, 21 F. R. 5220, July 13, 1956]

§ 14.16-2 Testing facilities (CAA policies which apply to § 14.16 (a)). The testing equipment available for conducting the tests specified in §§ 14.151 through 14.155 should be:

(a) An engine capable of developing at least the power and speed for which certification of the propeller is desired. (b) A suitable engine mount.

(c) An accurate tachometer, which should be calibrated before and after testing or checked with a stopwatch and revolution counter during testing.

(d) A suitable manifold pressure gage if the test is not run at full throttle (not required for fixed-pitch wood propeller tests). The manifold pressure connection should be permanently located so that the manifold pressure is a uniform indication of power. All test values should be on a basis of dry absolute manifold pressure which is obtained by subtracting the vapor pressure from the observed absolute manifold pressure. [Supp. 1, 21 F. R. 5220, July 13, 1956]

3

§ 14.16-3 Propeller operating limitations (CAA policies which apply to § 14.16 (c)). (a) The following operating limitations will be established as determined from tests conducted for type certification:

(1) Maximum continuous power and r. p.m.

(2) Takeoff power and r. p. m.

(3) When applicable, avoidance of continuous operation at or between certain r. p. m.

(4) When applicable, special limitations imposed due to functional or structural considerations, such as minimum engine oil pressure necessary and life limit.

(b) Requests for increases in power and/or r. p. m. ratings up to a maximum of 10 percent above the values substantiated by actual tests, provided there are no structural changes in the propeller, should be accompanied by substantiating test data or stress analysis as

The operating limitations together with diameter and pitch limits and general specifications for the propeller are published in the form of propeller specifications available free of charge from the Civil Aeronautics Administration, Aviation Information Office, W-47, Washington 25, D. C.

covered in § 14.14-1 (e), (f) and (h). Requests for increases greater than 10 percent should be substantiated in a manner satisfactory to the Administrator.

[Supp. 1, 21 F. R. 5220, July 13, 19561

§ 14.17 Production certificates. (For requirements with regard to production certificates see Part 1 of this subchapter.)

§ 14.18 Approval of materials, parts, processes, and appliances. (a) Materials, parts, processes, and appliances shall be approved upon a basis and in a manner found necessary by the Administrator to implement the pertinent provisions of the regulations in this subchapter. The Administrator may adopt and publish such specifications as he finds necessary to administer this regulation, and shall incorporate therein such portions of the aviation industry, Federal, and military specifications respecting such materials, parts, processes, and appliances as he finds appropriate.

NOTE: The provisions of this paragraph are intended to allow approval of materials, parts, processes, and appliances under the system of Technical Standard Orders, or in conjunction with type certification procedures for a propeller, or by any other form of approval by the Administrator.

(b) Any material, part, process, or appliance shall be deemed to have met the requirements for approval when it meets the pertinent specifications adopted by the Administrator, and the manufacturer so certifies in a manner prescribed by the Administrator.

§ 14.19 Changes in type design. (For requirements with regard to changes in type design and the designation of applicable regulations therefor, see § 14.11 (d) and (e), and Part 1 of this subchapter.) IDENTIFICATION AND INSTRUCTION MANUAL

§ 14.20 Propeller identification data. A certificated propeller, propeller blade, or propeller hub shall have displayed upon it conspicuously the identification data required by § 1.50 of this subchapter. The identification data shall be permanently attached upon a noncritical surface of the propeller, blade, or hub by means of a plate, stamping, engraving, etching, or other approved method. When such data are not visible when the propeller is assembled or installed on an aircraft, they shall also be painted or printed on the propeller, blade, or hub.

§ 14.21 Instruction manual. The applicant shall prepare and make available an approved manual containing instructions for the installation, operation, servicing, maintenance, repair, and overhaul of the propeller.

NOTE: It is not intended to limit the form of the manual to a single document.

SUBPART B-AIRWORTHINESS
DESIGN AND CONSTRUCTION

§ 14.100 Scope. (a) The propeller shall not incorporate design features or details which experience has shown to be hazardous or unreliable. The suitability of all questionable design details or parts shall be established by tests.

(b) The design and construction provisions of this part shall be applicable to the propeller when it is installed, operated, and maintained in accordance with the instruction manual prescribed in § 14.21.

§ 14.100-1 Design features (CAA policies which apply to § 14.100). Where applicable, the propeller should incorporate design features to comply with the requirements of pertinent portions of Parts 3 and 4b of this subchapter, regarding feathering and unfeathering, r. p. m. governing, de-icing, low pitch stops, r. p. m. and pitch controls, feathering controls, and reversing controls. [Supp. 1, 21 F. R. 5220, July 13, 1956]

§ 14.101 Materials. The suitability and durability of all materials used in the propeller shall be established on a basis of experience or tests. All materials used in the propeller shall conform to approved specifications which will insure their having the strength and other properties assumed in the design data.

§ 14.102 Durability. All parts of the propeller shall be designed and constructed to minimize the development of an unsafe condition of the propeller between overhaul periods.

§ 14.103 Reversible propellers. Reversible propellers shall be adaptable for use with a reversing system in an airplane so that no single failure or malfunctioning of the reversing system during normal or emergency operation will result in unwanted travel of the propeller blades to a position substantially below the normal flight low-pitch stop. Failure of structural elements need not be considered if the occurrence of such failure is expected to be extremely remote.

§ 14.150 General. The tests and inspections prescribed in §§ 14.151 through 14.157 shall be applicable to propellers, including all essential accessories. The propeller shall complete the prescribed tests without evidence of failure or malfunctioning.

§ 14.150-1 Essential accessories (CAA policies which apply to § 14.150). All accessories and appurtenances intended for use with the propeller should be included in the tests required in §§ 14.153, 14.154 and 14.155. These accessories and appurtenances include, but are not limited to:

(a) Propeller spinner.
(b) Propeller brakes.

(c) Propeller cuffs or fairings. (d) De-icing fluid slinger rings. (e) De-icing fluid distributing strips. [Supp. 1, 21 F. R. 5220, July 13, 1956]

§ 14.151 Centrifugal load test. The hub and blade retention arrangement of propellers with detachable blades shall be subjected to a centrifugal load equal to twice the centrifugal force to which the propeller is to be subjected in normal operation. Either one of the following two test methods shall be acceptable:

(a) A one-hour whirl test, or
(b) A static pull test.

4

§ 14.151-1 Centrifugal load test (CAA policies which apply to § 14.151)(a) Whirl test. The complete pro

4 So that it will not be necessary to repeat this test for new blade designs which would impose greater centrifugal loading on the retention system, it is suggested that the test selected be conducted at the greatest centrifugal loading anticipated.

The double centrifugal force loading for this test, the purpose of which is to substantiate the structural integrity of the blade retention arrangement, is based on the maximum continuous r. p. m. for which the propeller is to be certificated.

peller, or the propeller hub with weighted stub blades, may be used in this test. If stub blades are used, they should produce the required centrifugal force at the test r. p. m. Any type of motive power may be used for this test. The propeller may be reduced in pitch any amount so as to reduce the power if desired.

(b) Static pull test. Stub blades used for this test need not be formed into airfoil sections, but should be flared out to provide adequate holding means to insure that any failure will occur in the blade retention arrangement.

[Supp. 1, 21 F. R. 5220, July 13, 1956]

§ 14.152 Vibration test. Propellers with metal blades and/or metal hubs shall be subjected to a vibration test under sufficient conditions to establish the level of vibratory stresses in the blade and/or hub when the propeller is operated under all conditions of rotational speed and engine power which are to be established for the propeller. The test shall be conducted on the same or equivalent engine and the test stand configuration on which the endurance tests are conducted.

§ 14.153 Endurance test-(a) Fixedpitch wood propellers. Fixed-pitch wood propellers shall be subjected to one of the following endurance tests:

(1) A 10-hour endurance block test on an engine shall be conducted with a propeller of the greatest pitch and diameter for which certification is sought at the rated rotational speed.

(2) A 50-hour flight test shall be conducted in level flight or in climb. At least 5 hours of this flight test shall be conducted with the propeller operated at the rated rotational speed, and the remainder of the 50 hours shall be conducted with the propeller operated at not less than 90 percent of the rated rotational speed.

(3) A 50-hour endurance block test on an engine shall be conducted at the power and propeller rotational speed for which certification is sought.

(b) Fixed-pitch metal propellers and adjustable-pitch propellers. Fixed-pitch propellers with metal blades and adjustable-pitch propellers shall be subjected to one of the endurance tests prescribed in paragraph (a) (2) and (3) of this section.