Text in force at 23-63: from 23-59, effective 23 Dec 2008.
(a) Each propeller must have a type certificate.
(b) Engine power and propeller shaft rotational speed may not exceed the limits for which the propeller is certificated.
(c) Each featherable propeller must have a means to unfeather it in flight.
[ (d) The propeller blade pitch control system must meet the requirements of Sec. Sec. 35.21, 35.23, 35.42 and 35.43 of this chapter.]
(e) All areas of the airplane forward of the pusher propeller that are likely to accumulate and shed ice into the propeller disc during any operating condition must be suitably protected to prevent ice formation, or it must be shown that any ice shed into the propeller disc will not create a hazardous condition.
(f) Each pusher propeller must be marked so that the disc is conspicuous under normal daylight ground conditions.
(g) If the engine exhaust gases are discharged into the pusher propeller disc, it must be shown by tests, or analysis supported by tests, that the propeller is capable of continuous safe operation.
(h) All engine cowling, access doors, and other removable items must be designed to ensure that they will not separate from the airplane and contact the pusher propeller.
73 FR 63345 · Source