EN-1320
OPERATION AND INSTALLATION MANUAL
6.4. INSPECTION PROCEDURES
NOTE: This section contains inspection procedures to evaluate reason of troubles determined
within the inspections stated above. In some instances, the repair procedure is included.
1) Grease or Oil Leakage
a) Oil leakage is usually caused by damaged seal. Inspect the propeller and identify source
of leakage.
2) Vibration
WARNING: ABNORMAL VIBRATION CAN INDICATE THE DAMAGE OF PROPELLER
BLADE OR BLADE BEARING COMPONENT. IT MAY LEAD TO IN-FLIGHT
BLADE SEPARATION AND CATASTROPHIC AIRCRAFT ACCIDENT !
THE SOURCE OF VIBRATION MUST BE IMMEDIATELY DETERMINED
AND CORRECTED.
a) Troubleshooting procedures typically begin with an investigation of the engine. Aircraft
components, such as engine mounts or loose landing gear doors, can be the source of
vibration. Perform evaluation of possible sources of vibration in accordance with engine
and/or aircraft manufacturer´s instructions. If no cause is found, proceed according the
following steps.
b) Remove the spinner dome and visually inspect the entire blades and visible hub
components for cracks, mechanical damage and other unusual condition. If crack is
found or in case of any doubt contact Avia Propeller.
c)
Thread-type blade models only
Check correct installation of the blades in the bushings. Verify that the position line on the
blade shank coincide with the line on the blade bushing face. Max. tolerance for blade
and bushing marks straightness is one half of blade mark thickness. Reinstall the blade
per Installation and operation instruction in this manual if problem is noted.
d) Check correct installation of the clamps with counterweights. Refer to Installation and
operation instruction in this manual.
e) Check the blade play per Loose blades section in this chapter.
f) Check the blade track per Blade track section in this chapter.
3) Loose Blades
a) Check the blade for looseness per figure 6-2.
Blade play limits:
Blade end play: ±2,0 mm (
±
0.08 inch)
Fore and aft play: ±2,0 mm (
±
0.08 inch)
Radial play (pitch change):
±
0,5 degree (1 degree total) measured at reference station -
difference between all blades must not be more than 0,5°.
In and out play: 0,8 mm (0.032 inch)
CAUTION:
DO NOT APPLY AN EXCESSIVE FORCE TO THE BLADE WHEN CHECK
THE BLADE PLAY. THE FORCE 1 N TO 4 N IS ACCEPTABLE.
61-10-20
INSPECTIONS
Page 6-6
2017-10-06
