RII on props

[nhcw231885]

Hi,

Any body knows why CARs never require independent check on propeller related works like props change? if props failed, it could be a catastrophic result, same as flight control and engine.

Any ideas would be appreciated.

[PilotDAR]

Well.... My initial reaction to the question is that beyond the simple work described in AC43.13-1B, all constant speed propeller maintenance has to be accomplished by an AMO, which has demonstrated a standard of maintenance quality control to TC. The installation of either type of propeller is described in the airplane maintenance manual, and is not fraught with opportunities to get it wrong, for qualified airplane maintainers.

Aside from blade separation, the failure of a constant speed propeller control system, though not great, would unlikely be catastrophic. The design requirements require some exceedance protection in the propeller system design.

I am aware of propeller installation problems in the past. In all cases in my recollection, truly faulty maintenance practices were applied by non qualified owners on amateur built airplanes. Not to knock amateur builts, but their maintainers still have to apply good practices!

[hangarline]

From ANC010.

For the purposes of this notice"flight and engine controls" includes all controls by which the propulsive force or flight path of an aircraft can be altered, and includes both primary and secondary controls.

In my opinion, a propeller would be considered a "propulsive force". In the case of a fixed pitch prop, the security of any locking devices should have an independent inspection. (lockwire) In the case of constant speed props, the same locking devices to the mounting of the prop in addition to the controls for the prop.

[SeptRepair]

From ANC010.

For the purposes of this notice"flight and engine controls" includes all controls by which the propulsive force or flight path of an aircraft can be altered, and includes both primary and secondary controls.

In my opinion, a propeller would be considered a "propulsive force". In the case of a fixed pitch prop, the security of any locking devices should have an independent inspection. (lockwire) In the case of constant speed props, the same locking devices to the mounting of the prop in addition to the controls for the prop.

A prop is propulsive, but it is controlled by a prop governor. The control is what is inspected and verified to conform. No need for an independent check of lockwire or nuts on installation of the prop. independent Inspection of the nuts, lockwire, and cotter pins of the control is needed. The maintenance release covers the prop install.

[‘Bob’]

From ANC010.

For the purposes of this notice"flight and engine controls" includes all controls by which the propulsive force or flight path of an aircraft can be altered, and includes both primary and secondary controls.

In my opinion, a propeller would be considered a "propulsive force". In the case of a fixed pitch prop, the security of any locking devices should have an independent inspection. (lockwire) In the case of constant speed props, the same locking devices to the mounting of the prop in addition to the controls for the prop.