Text in force at CS25-28: from CS25-18, effective 24 Jun 2016.
(See AMC 25.905)
(a) reserved (b) Engine power and propeller shaft rotational speed may not exceed the limits for which the propeller is certificated. (See CS-P 50) (c) Each component of the propeller blade pitch control system must meet the requirements of CS-P 420. (d) Design precautions must be taken to minimise the hazards to the aeroplane in the event a propeller blade fails or is released by a hub failure. The hazards which must be considered include damage to structure and critical systems due to impact of a failed or released blade and the unbalance created by such failure or release. (See AMC 25.905 (d))
ED Decision 2016/010/R · Source