MOONEY
M20TN - MODEL TYPE-S
SECTION VII
AIRPLANE AND SYSTEM DESCRIPTION
7 -- 22
AIRPLANE FLIGHT MANUAL
ORIGINAL ISSUE -- 04-02-2008
AIR INDUCTION SYSTEM
The primary engine air induction system draws air from the upper cowling plenum through the
engine cooling inlets. The air passes through a filter and is split to provide air to the left and right
turbo. The standard air filter is cleanable and must be serviced at 100 hour intervals. Refer the
service and maintenance manual for instructions.
AIR INLET
FILTER
FUEL
CONTROL
UNIT
ALT.
AIR
BOX
ENGINE INDUCTION
AIR SYSTEM
FILTER CAN
ENGINE
INT
E
RCOOL
ER
LH
INT
E
RCOOL
ER
RH
FRONT
OF
AIRCRAFT
LH TURBO
RH TURBO
AIR INLET
LOWER COWL
PLENUM
UPPER COWL
PLENUM
FIGURE 7--6 AIR INDUCTION SYSTEM SCHEMATIC
A secondary or alternate air source for combustion air is provided. It has a door which normally
remains closed and is held by a magnetic catch. If the air filter or induction air inlet is restricted
beyond a minimum allowable inlet pressure, the alternate air door will automatically open.
Warmer air will then be drawn from the engine compartment. There will be a reduction of engine
power when the alternate air door is open due to lower inlet air pressure and higher air tempera-
ture. Whenever the alternate air door is open, a switch will activate the ”ALT AIR” annunciator
light on the panel to alert the pilot.
