ASA Electronics cx-3 - ALTITUDE

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Problem: What is the PAlt at an airport with a
eld elevation of 5,900 feet and a 29.75" Hg
altimeter setting?
Solution:
Press the key. Highlight the
Altitude line and tap enter. Enter IAlt:
and tap enter.
Enter the altimeter setting:
and tap enter.
The display will show PAlt equal to 6059 FT.
Density Altitude
In aviation calculations, air density is normally
specied by an altitude in a standard atmosphere,
instead of pounds per cubic foot. The altitude
corresponding to a given density is called the density
altitude (DAlt). The Altitude function computes density
altitude (DAlt) based on pressure altitude (PAlt) and
the outside air temperature (OAT).
Problem: What is the DAlt at an airport with
a eld elevation of 5,900, 29.75" Hg altimeter
setting, and 75°F OAT?
Solution:
Press the key. Highlight the Altitude
line and tap enter. Enter IAlt:
and tap enter.
Scroll the curser to Baro and enter the altimeter
setting:
and tap enter.
Scroll down to OAT and input , tap enter.
The display will show PAlt equal to 6059 FT and
DAlt equal to 8427 FT.
◗ CLOUD BASE
The Cloud Base function computes the altitude of the
cloud base above ground level (AGL). The function
prompts for the dew point (Dewp) and outside air
temperature (OAT) at the aireld. If you want the
elevation of the cloud base above mean sea level
(MSL), you must add the elevation of the aireld to
the result from the Cloud Base function.
Problem: At approximately what altitude above
the surface can the pilot expect the base
of cumuliform clouds to be if the surface air
temperature is 82°F and the dew point is 38°F?
Solution:
Press the key. Scroll to Cloud Base
and tap enter. You are prompted for the outside
air temperature (OAT). Press:
and tap enter.
You are then prompted for dew point (Dewp).
Press:
and tap enter.
The answer is 10,000 FT AGL.
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◗ ALTITUDE
Pressure Altitude
In aviation calculations, air pressure is normally
specied by an altitude in a standard atmosphere,
instead of pounds per square inch or inches of
mercury. The altitude corresponding to a given
pressure is called the pressure altitude (PAlt). An
aviation altimeter displays PAlt when the altimeter
setting window is adjusted to the standard
atmospheric pressure at sea level, 29.92" Hg. PAlt is
required to calculate true airspeed (TAS) and density
altitude (DAlt).
The Altitude function calculates pressure altitude
(PAlt), given the indicated altitude (IAlt) and altimeter
setting (Baro) obtained from the automated ight
service station (AFSS) or Air Trafc Control (ATC).
An altimeter adjusted to this setting will indicate
the altitude of the aireld when the aircraft is on the
ground.
Problem: You are planning to y at 4,500 feet
IAlt and the current altimeter setting is 30.15" Hg.
What PAlt should you use to calculate the TAS?
Solution:
Press the key. Highlight the
Altitude line and tap enter. Enter IAlt by pressing
and tap enter. Enter the altimeter
setting:
and tap enter.
The display will show PAlt equal to 4289 FT.
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E6-B 10:34
Altitude
Unit Conversions
Cloud Base
Ground Speed
To - From
Airspeed
Climb & Descent
Wind Correction
Holding Pattern
Fuel
Estimated Time Arrival
Wind Component
Rhumb Line
Standard Atmosphere
Glide
Compass Heading