INSPECTION AND CHECK
61-00-39
Page 5-21
Rev. 17 Apr/20
Propeller Owner’s Manual
139
C. Vibration
(Rev. 1)
NOTE: Vibration may originate in the engine, propeller,
or airframe. Troubleshooting procedures typically
begin with an investigation of the engine. Airframe
components, such as engine mounts or loose
landing gear doors, can also be the source
of vibration. When investigating an abnormal
vibration, the blades and the blade retention
components should be considered as potential
sources of the vibration.
(1) Important Information
(a) Instances of abnormal vibration should be
investigated immediately. If the cause of the vibration
is not readily apparent, examine the propeller in
accordance with the instructions in this section.
(b) Perform troubleshooting and evaluation of possible
sources of vibration in accordance with engine or
airframe manufacturer’s instructions.
(c) Refer to the section, “Vibration” in the Testing and
Troubleshooting chapter of this manual.
1 Perform the checks to determine possible cause
of the vibration.
a If no cause is found, the propeller could be
the source of the vibration. Examine the
propeller in accordance with the Inspection
steps in this section.
(2) Inspection
(a) Remove the spinner dome.
(b) Visually examine the hub, blades, and blade clamps
(if applicable) for cracks.
1 Pay particular attention to the blade retention
areas of an aluminum hub, or the blade clamps
on steel hub propellers.
2 A crack may be readily visible, or may be
indicated by grease leaking from a seemingly
solid surface.
