ASA Electronics cx-3 - PLANNED MACH#; ACTUAL MACH#; GROUND SPEED; FUEL

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Planned MACH#
The Airspeed function can compute true airspeed for
a planned MACH with the inputs Planned MACH and
OAT. It is important to use the OAT at the planned
ight altitude. The Airspeed function computes TAS,
and TAT (to be used as a cross-check against the
in-ight TAT).
Problem: Compute TAS for 0.72 MACH and
-31°F OAT.
Solution: Press the key. Select the Airspeed
submenu. Press:
and tap enter to input 0.72 MACH,
and then
and tap enter to input
-31°F OAT.
The display will now show 432.98 KTS TAS and
13°F TAT.
Actual MACH#
The Airspeed function can compute true airspeed
using information from instruments during an actual
ight. The inputs to this function are Actual MACH,
and TAT. The Act MACH# function calculates TAS,
and OAT.
Problem: Compute the TAS given 0.82 MACH
with -4°F TAT.
Solution: Press the key. Select the Airspeed
submenu by scrolling to the Airspeed line. Tap
enter. Press:
and tap enter to input 0.82 MACH,
and then
and tap enter to input -4°F T
AT.
The display will show 477.32 KTS TAS and -58°F
OAT.
◗ FUEL
Fuel Burn
The Fuel function calculates the amount of fuel (Vol)
consumed over a specied time Duration (Dur) at a
specied rate (Rate).
Problem: How much fuel will burn in 1 hour, 14
minutes, and 38 seconds at a rate of 9.5 gallons
per hour?
Solution:
Press the key. Select the Fuel
submenu. Scroll to Dur and press , to get
HMS. Next press:
and tap enter to
input 1:14:38 HMS Dur, and then:
and tap enter to
input 9.5 U.S. GPH
Rate.
The display will show 11.82 U.S. GAL VOL.
Fuel Rate
The Fuel function calculates the fuel rate (Rate) from
the amount of fuel (Wt) consumed over a given time
duration (Dur).
Problem: What is rate of fuel consumption if
9,500 pounds of fuel were burned in the last 2
hours, 30 minutes?
Solution:
Press the key. Select the Fuel
submenu. Scroll to Dur and press:
and tap enter to
input 2:30 HMS Dur, and then scroll to Wt and
press:
and tap enter to input 9,500 LBS
of Fuel.
The display will show a Rate of 3,800 LBS/HR.
Endurance
The Fuel function can calculate the duration of
time (Dur) a specied amount of fuel (Vol) will be
consumed at a specied rate (Rate).
Problem: How much ight time do you have with
38 gallons of fuel on board, and a power setting
that gives a fuel burn rate of 9.5 gallons per hour?
Solution: Press the key. Select the Fuel
submenu. Press:
and tap enter to input 38 U.S. GAL Vol,
and then:
and tap enter to input 9.5 U.S. GPH
Rate.
The display will show 3:59:59 HMS Dur (3 hours,
59 minutes, 59 seconds).
◗ GROUND SPEED
The Ground Speed function computes ground speed
given a distance (Dist) and ight duration (Dur).
Problem: What is the ground speed if 5 nautical
miles are own in 2 minutes, 32 seconds?
Solution:
Press the key. Select the Ground
Speed submenu. Press:
and tap enter to input 5 NM Dist. Press to
get HMS, then
and tap enter to
input 00:02:32 HMS Dur.
The display will show 118.42 KTS GS.
F LT
3 8
9 . 5
F LT
2 : 3 0 : 0 0
0059
F LT
5
0 0 : 0 2 : 3 2
F LT
1 : 1 4 : 3 8
5.9
F LT
. 7 2
3 1
+
−
F LT
. 8 2
4
+
−
CONV
UNIT