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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
flight altitude . The Airspeed function computes TAS,
and TAT (to be used as a cross-check against the
in-flight 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
flight . 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 TAT .
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 specified time Duration (Dur) at a
specified 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 specified amount of fuel (Vol) will be
consumed at a specified rate (Rate) .
Problem:
How much flight 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 flight duration (Dur) .
Problem:
What is the ground speed if 5 nautical
miles are flown 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 .
FLT
3
8
9
.
5
FLT
2
:
3
0
:
0
0
0
0
5
9
FLT
5
0
0
:
0
2
:
3
2
FLT
1
:
1
4
:
3
8
5
.
9
FLT
.
7
2
3
1
+
−
FLT
.
8
2
4
+
−
CONV
UNIT
