Hartzell HC-B3-2 Series Owner's Manual And Logbook page 196

(b) Perform an engine run up and determine if the
engine and/or propeller rigging permits operation of
the propeller below the minimum specified propeller
idle RPM.
(c) If the propeller cannot be operated below the
minimum specified propeller idle RPM, no further
action is required.
(d) If the propeller can be operated below the minimum
specified propeller idle RPM:
1
2
Example:
Minimum propeller idle RPM listed in the AMM is 1180 RPM
Propeller idle is set at 1120 RPM
Propeller has operated with a RPM deviation of 60 RPM
Engine was rigged 2 months ago and has operated 75 hours
since it was rigged
Figure 5-1 shows that with an RPM deviation of 60 RPM for
75 hours - the propeller assembly must be overhauled and
engine rigging corrected before further flight.
Example of a Ground Idle RPM Check Evaluation
INSPECTION AND CHECK
Propeller Owner's Manual
Refer to Figure 5-1 for corrective action
requirements, and Figure 5-2 for an example of
a ground idle RPM check evaluation.
The corrective action is based on the amount the
RPM is below the minimum propeller idle RPM
and the total hours of operation the propeller has
accumulated.
a Figure 5-1 applies to an aircraft that is
operated in conventional service. "Hours
of Operation" refers to the total number
of hours the propeller is operated on an
engine that has an improper RPM setting. It
is not the number of hours the propeller is
operated in a restricted range, which will be
less than the total hours of operation.
Figure 5-2
139
61-00-39
Rev. 17 Apr/20
Page 5-10