Here are two that I studied during my Masters coursework:
Convair 580 and
Embraer Brasilia
In the first, the pitch actuating mechanism failed due to heavy wear. Although a special oil analysis inspection was in place to detect the wear, it failed to do so. The failure occurred during high IAS, leading to very rapid overspeed and blade failure, cutting the fuselage in two.
In the second, the pitch feedback leadscrew failed due to wear. A preflight runup check failed to detect the incipient failure. The failure occurred during approach, causing high yawing moment and wing airflow disruption on one side, with uncontrollable roll.
Both accidents had common factors:
1) The physical characteristic of all variable-pitch propeller blades to migrate to fine (low) pitch when control forces are absent.
2) maintenance/inspection programs which proved inadequate.
The first point is a fact that Hamilton Standard, which has built controllable props since the early 30s, and the FAA certification branch seemed to have jointly forgotten by the 80s; The Failure Modes, Effects, and Criticality Analysis of the HS prop on the Brasilia was remarkably "lightweight".
Interesting speculation: IF the Brasilia failure had occurred at high IAS, the overspeed might have caused the prop blades to fail, but their lightweight composite design might have prevented them from penetrating the fuselage, which had occurred in the CV580 accident.