[Code of Federal Regulations]

[Title 14, Volume 1]

[Revised as of January 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 14CFR35.39]



[Page 809-810]

 

                     TITLE 14--AERONAUTICS AND SPACE

 

CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION

 

PART 35_AIRWORTHINESS STANDARDS: PROPELLERS--Table of Contents

 

                     Subpart C_Tests and Inspections

 

Sec. 35.39  Endurance test.



    (a) Fixed-pitch wood propellers. Fixed-pitch wood propellers must be 

subjected to one of the following tests:

    (1) A 10-hour endurance block test on an engine 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 in level flight or in climb. At least five 

hours of this flight test must be with the propeller operated at the 

rated rotational speed, and the remainder of the 50 hours must be with 

the propeller operated at not less than 90 percent of the rated 

rotational speed. This test must be conducted on a propeller of the 

greatest diameter for which certification is requested.

    (3) A 50-hour endurance block test on an engine at the power and 

propeller rotational speed for which certification is sought. This test 

must be conducted on a propeller of the greatest diameter for which 

certification is requested.

    (b) Fixed-pitch metal propellers and ground adjustable-pitch 

propellers. Each fixed-pitch metal propeller or ground adjustable-pitch 

propeller must be subjected to the test prescribed in either



[[Page 810]]



paragraph (a)(2) or (a)(3) of this section.

    (c) Variable-pitch propellers. Compliance with this paragraph must 

be shown for a propeller of the greatest diameter for which 

certification is requested. Each variable-pitch propeller (a propeller 

the pitch setting of which can be changed by the flight crew or by 

automatic means while the propeller is rotating) must be subjected to 

one of the following tests:

    (1) A 100-hour test on a representative engine with the same or 

higher power and rotational speed and the same or more severe vibration 

characteristics as the engine with which the propeller is to be used. 

Each test must be made at the maximum continuous rotational speed and 

power rating of the propeller. If a takeoff rating greater than the 

maximum continuous rating is to be established, and additional 10-hour 

block test must be made at the maximum power and rotational speed for 

the takeoff rating.

    (2) Operation of the propeller throughout the engine endurance tests 

prescribed in Part 33 of this subchapter.



[Doc. No. 2095, 29 FR 7458, June 10, 1964, as amended by Amdt. 35-2, 32 

FR 3737, Mar. 4, 1967; Amdt. 35-3, 41 FR 55475, Dec. 20, 1976]