Section 7
Columbia 400 (LC41-550FG)
Description of the Airplane and Systems
Initial Issue of Manual: November 10, 2004
RC050002
Latest Revision Level/Date: -/11-10-2004
7-23
INSTRUMENTS
ENGINE INSTRUMENT PANEL
The operation and use of engine instruments and the instruments for accessory items connected
to the engine, such as the alternators, are discussed below. While some of these instruments
display information about systems that are not directly related to the operation of the engine, they
are included here for convenience to permit discussion and referencing under one heading. In
addition, reference is made to the annunciator panel since many of its indications are associated
with the engine and engine related instruments. The annunciator panel is described in more detail
on page 7-25 of this section. The instruments discussed below are in the engine instrument panel,
which is on the left side of the airplane to the left of the flight instrument panel. The panel is
canted about 30
°
in relation to the flight instrument panel.
See Figure 7 - 3 for a drawing of the
instrument panel.
Fuel Quantity
– The fuel quantity
gauges are in the engine instrument panel in the top-left
position. The instrument is a dual presentation gauge with the left tank fuel quantity on the left
side and the right tank fuel quantity on the right side. The gauge displays the amount of available
usable fuel, in US gallons, in each tank. The dials for each gauge range from 0 gallons (red
placard) to 49 gallons with major increments of 10 gallons and minor increment of 5 gallons.
There are two green lights on the left and right side of the gauge that illuminate to indicate which
tank is selected. The lights will only work when the fuel selector is properly seated in the left or
right position. Controlling light intensity and testing these lights is discussed later in this section
on page 7-64. The pilot is reminded that the fuel gauges are approximate indications and are
never substitutes for proper planning and pilot technique.
Manifold Pressure –
The manifold pressure gauge is in the engine instrument panel in the top-
right position. The instrument is a dual presentation gauge with manifold pressure indications on
the left and fuel flow readings on the right. Changes in throttle settings are displayed on the
manifold pressure gauge in inches of mercury (inches of Hg) as it measures the absolute pressure
in the engine intake manifold, behind the throttle valve. The manifold pressure gauge has
increments that range from 0 to 40 inches of Hg. A white arc extends from 33.5 to 35.5 inches of
Hg. A green arc extends from 15 to 33.5 inches of Hg. And a red radial is located at 35.5 inches
of Hg. The electronically powered gauge will not operate with the master switches off.
Fuel Flow –
The fuel flow
gauge is in the engine instrument panel in the top-right position. The
instrument is a dual presentation gauge with manifold pressure indications on the left and fuel
flow readings on the right. Changes in throttle or mixture settings will produce changes in the
fuel flow readings. Readings for this gauge are obtained by measuring the fuel pressure on the
metered side of the fuel system and converting it into a related fuel flow reading. The instrument
displays gallons per hour (GPH) and ranges from 0 GPH to 40 GPH with a red radial at 40 GPH.
The gauge is electronically operated and will not display a reading with the master switches
turned off.
Dual Ammeter/Loadmeter –
The ammeter is in the engine instrument panel in the center-left
position. The ammeter is a dual presentation gauge that measures the condition of both batteries
and alternators in terms of charging or discharging. Because the instrument shows the condition
of both the batteries and the alternators, it may be considered a loadmeter, but will be called an
ammeter throughout this manual.