MANUFACTURER: Dowty Propellers Type
R212/4-30-4/22 and R251/4-30-4/49 Propeller Assemblies SUBJECT: Airworthiness Directive 2011-19-02 ACTION: Final rule.
SUMMARY: This AD results from mandatory
continuing airworthiness information (MCAI) issued by an aviation
authority of another country to identify and correct an unsafe
condition on an aviation product. The MCAI describes the unsafe
Reports have been received from a
small number of HS.748 operators of finding cracks in the propeller
hub port buttress threads of R212 and R251 propellers. The affected
hubs had accumulated in excess of 6,000 flight hours. This
condition, if not detected and corrected, could lead to propeller
blade separation, possibly resulting in damage to the aeroplane
and/or injury to persons on the ground.
The FAA is issuing this AD to prevent propeller hub failure due
to cracks in the hub, which could result in damage to the