Extra 300/SC, Руководство по обслуживанию

Страница: 193 / 250

CHAPTER 61
PAGE 4
MAINTENANCE MANUAL EXTRA 300/SC
PAGE DATE: 12. February 2019
61-20-00 CONTROLLING
The propeller blade pitch change is conducted by a governor
(refer to Figure 1). Once an engine rotational speed is
selected it will be held constant independent of airspeed or
power variations.
Mechanical stops for low pitch and high pich within the hub
limit the pitch change level. In case the oil pressure of the
govenor is lost, the blades automatically return to high pitch.
The oil pressure is single acting.
The governor itself is actuated via a vernier control cable
ending on the left side of the rear cockpit (blue control knob;
1, Figure 1 & 8, Figure 2). This cable is routed on the left side
of the fuselage, penetrates the firewall, the rear engine
baffles and is then routed to the governor. The cable is
attached at its front end to the engine by a clamp block and in
the cockpit area to the steel tube structure by self-clinching
plastic tiedown straps. The RPM vernier control unit is
mounted to a fuselage bracket. The firewall and engine baffle
penetrations are covered with clamp sheets. The firewall
penetration (2, Figure 1) is additionally sealed with firewall
sealant.
Figure 1 Controlling