EN-1320
OPERATION AND INSTALLATION MANUAL
c) Purge the propeller control system:
1 Place the engine condition lever into idle position.
2 Move the propeller condition lever into feather position, propeller RPM reduces to
≈
350 rpm.
3 Move back the propeller condition lever after about
≈
15 s delay to maximum RPM position and wait
to previous RPM.
4 Repeat the cycle 3 times, wait about 40 s at the idle between the cycles.
d) Propeller RPM check at idle (only for twin engine aircrafts).
1 Set engine condition lever to idle.
2 Move the propeller condition lever to maximum RPM position.
3 RPM difference should be 40 RPM max. If higher, correct it according to procedure in this section.
e) Maximum propeller RPM check.
1 Propeller control lever in maximum RPM position.
2 Move engine control lever to maximum take-off power position.
3 Maximum ground propeller speed should be 2080 -120 rpm.
NOTE:
Specified value for RPM is only for information. It depends on engine performance and atmospheric
conditions.
f) Feathering pump heating leg pressure check (only when the feathering pump is installed).
1 Move engine control lever to maximum continuous power position.
2 “Feathering Pump” is not lit.
g) Propeller control lever function check.
1 Engine control lever at maximum continuous power position.
2 Set - with engine control lever - propeller RPM to 1900 rpm, then reduce propeller RPM to 1700 rpm
using propeller control lever and back to previous position.
3 Propeller speed must be adequate to position of propeller control lever.
WARNING: TORQUE MUST NOT EXCEED 100%!
h) Speed in reverse mode, reverse power check, secondary pitch lock check.
1 Set propeller control lever to maximum RPM position.
2 Place engine control lever to idle.
3 Move engine control lever over the stop, move slowly and smoothly into maximum reverse position
- and observe operational values:
a Propeller speed – moving the engine control lever, increases up to stabilization (approx. 1100 to
1200 rpm) even engine control lever movement continues.
b Energizing the BETA lamp – fast increase follows (to value approximately 1400 to1500 rpm).
c Generator speed – increases when BETA lamp is energized
4 If described development corresponds to observed actions, secondary pitch lock works correctly.
5 Move engine control lever slowly and smoothly into maximum reverse position - for period sufficient
to read operational values. Verify power in reverse mode of operation with engine operational
manual. Maximum reverse speed is 2030 rpm.
6 Move engine control lever slowly and smoothly back over idle stop.
a Propeller speed - follows engine control lever position, continuously drops to idle.
b Generator speed – immediate drop to idle, hold.
c BETA lamp de-energized – at about 1100 rpm.
61-10-20
PROPELLER CONTROL SYSTEM
(Installation With Jihostroj LUN-Series Governor)
Page 12-29
2017-10-06