Engine Controls - Piper SEMINOLE 2013 Pilot Operating Handbook

SECTION 7
DESCR/OPERATION
7.5 ENGINES AND PROPELLERS (continued)
Unfeathering Accumulators
Unfeathering accumulators store engine oil under pressure from
the governors, which is released back to the governors for propeller
unfeathering when the propeller control lever is moved out of the feathered
position.
A feathering lock, operated by centrifugal force, prevents feathering
during engine shutdown by making it impossible to feather any time
the engine speed falls below 950 RPM. For this reason, when feathering
a propeller in flight, the pilot must move the propeller control into the
FEATHER position before the engine speed drops below 950 RPM.

7.7 ENGINE cONTROLS

Engine controls consist of a throttle, a propeller control and a mixture
control lever for each engine. These controls are located on the control
quadrant on the lower center of the instrument panel where they are accessible
to both the pilot and the copilot (Figure 7-1). The controls utilize teflon-lined
control cables to reduce friction and binding.
The throttle levers are used to adjust the engine manifold pressure. A gear
up warning system, triggered by low manifold pressure, is intended to alert
the pilot of an impending gear up landing. When ever manifold pressure drops
below 14 inHg with the landing gear not down and locked, a CHECK GEAR
CAS message is activated along with a continuous CHECK GEAR aural alert.
If the airplane is higher than approximately 400 feet AGL, the CAS CAUTION
is triggered. Below 400 feet AGL, the CAS WARNING is triggered. Since
this low manifold condition might be experienced during normal descent,
the CHECK GEAR aural alert may be muted by pressing the appropriate
MASTER RESET switch above the PFD. Once muted, the aural alert is
silenced, but the associated CHECK GEAR CAS text message will remain
present until manifold pressure is increased, or the gear is deployed.
All throttle operations should be made with a smooth, not too rapid
movement to prevent unnecessary engine wear or damage to the engines.
REPORT: VB-2307
7-4
PA-44-180, SEMINOLE
ISSUED: June 5, 2013