Airspeed Indicator; Vertical Speed Indicator; Altimeter; Vacuum System And Instruments - Cessna 1980 182Q Pilot's Operating Handbook And Flight Manual

SECTION 7
AIRPLANE
&
SYSTEMS DESCRIPTIONS
alternate static source valve should be pulled on.
CESSNA
MODEL 182Q
Pressures within the cabin will vary with heater/vents opened or
closed, and windows qpen. Refer to Sections 3 and 5 for the effect of varying
cabin pressures on airspeed and altimeter readings.
AIRSPEED INDICATOR
The airspeed indicator is calibrated in knots and miles per hour.
Limitation and range markings (in KIAS) include the white arc (45 to 95
knots), green arc (48 to 143 knots), yellow arc (143 to 179 knots), and a red
line (179 knots).
If
a true airspeed indicator is installed, it is equipped with a rotatable
ring which works in conjunction with the airspeed indicator dial in a
manner similar to the operation of a flight computer. To operate the
indicator, first rotate the ring until pressure altitude is aligned with
outside air temperature in degrees Fahrenheit. Pressure altitude should
not be confused with indicated altitude. To obtain pressure altitude,
momentarily set the barometric scale on the altimeter to 29.92 and read
pressure altitude on the altimeter. Be sure to return the altimeter baromet-
ric scale to the original barometric setting after pressure altitude has been
obtained. Having set the ring to correct for altitude and temperature, read
the true airspeed shown on the rotatable ring by the indicator pointer. For
best accuracy, the indicated airspeed should be corrected to calibrated
airspeed by referring to the Airspeed Calibration chart in Section 5.
Knowing the calibrated airspeed, read true airspeed on the ring opposite
the calibrated airspeed.
VERTICAL SPEED INDICATOR
The vertical speed indicator depicts airplane rate of climb or descent in
feet per minute. The pointer is actuated by atmospheric pressure changes
resulting from changes of altitude as supplied by the static source.
ALTIMETER
Airplane altitude is depicted by a barometric type altimeter. A knob
near the lower left portion of the indicator provides adjustment of thei
instrument's barometric scale to the current altimeter setting.
VACUUM SYSTEM AND INSTRUMENTS
An engine-dnven ,-acuum system (see figure 7-9) provides the suction
7-34
1 October 1979