Textron Cessna C172S PIM, Pilot Operating Handbook

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CESSNA SECTION 1
MODEL 172S NAV III GENERAL
GFC 700 AFCS
U.S.
SYMBOLS, ABBREVIATIONS AND TERMINOLOGY
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METEOROLOGICAL TERMINOLOGY
OAT Outside Air Temperature is the free air static
temperature. It may be expressed in either degrees
Celsius or degrees Fahrenheit.
Standard
Temperature
Standard Temperature is 15°C at sea level pressure
altitude and decreases by 2°C for each 1000 feet of
altitude.
Pressure
Altitude
Pressure Altitude is the altitude read from an
altimeter when the altimeter's barometric scale has
been set to 29.92 inches of mercury (1013 mb).
ENGINE POWER TERMINOLOGY
BHP Brake Horsepower is the power developed by the
engine.
RPM Revolutions Per Minute is engine speed.
Static RPM Static RPM is engine speed attained during a full
throttle engine runup when the airplane is on the
ground and stationary.
Lean
Mixture
Decreased proportion of fuel in the fuel-air mixture
supplied to the engine. As air density decreases, the
amount of fuel required by the engine decreases for a
given throttle setting. Adjusting the fuel-air mixture to
provide a smaller portion of fuel is known as "leaning"
the mixture.
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