[Code of Federal Regulations]
[Title 14, Volume 1]
[Revised as of January 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 14CFR35.39]

[Page 777]
 
                     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 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]