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Problem:
The same aircraft from the previous
problem has a ground speed of 90 knots . What is
the rate of descent?
Solution:
Press:
and tap enter for 90 KTS GS .
The answer is 250 FPM RoC/D
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WIND COMPONENT
The Wind Component function computes the
headwind or tailwind component and the left or right
crosswind component for a given wind and runway .
The wind speed can be in knots, miles per hour or
kilometers per hour .
Since runways are numbered by their magnetic
course, the wind direction must be magnetic as
well (predicted winds aloft are given in true, rather
than magnetic orientation, while airport wind
advisories and runway headings are both magnetic) .
The runway number must be entered—not the
course . The inputs are WSpd, WDir, and Runway .
Remember: it must be the runway number, not the
heading . For example, runway 27 (not 270), and
runway 9 (not 90) . The outputs are crosswind
(X Wnd)—negative is a left crosswind, positive is a
right crosswind; headwind (H Wnd)—positive is a
headwind, negative is a tailwind .
Problem:
Assume a wind of 350° at 10 knots .
What are the head/tailwind and crosswind
components for a landing on runway 03?
Solution:
Press the key . Select the Wind
Component submenu . Press:
and tap enter for 10 KTS WSpd, then
and tap enter for 350° WDir, then
and tap enter for Runway 3 .
The answer will be -6 .43 KTS X Wnd (the negative
sign indicates a left crosswind) and 7 .66 KTS H
Wnd (a positive number indicates a headwind) .
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ESTIMATED TIME ARRIVAL
The Estimated Time Arrival function computes the
estimated time of arrival (ETA), given the departure
time (Dep) and flight duration (Dur) .
Problem:
What is your ETA if you plan to depart
at 9:30 a .m . for a 2 .5 hour flight?
Solution:
Press the key . Select the Estimated
Time Arrival submenu . Press:
to enter 2 .5 HR Dur, then
and tap enter to set
9:30:00 UTC Dep .
The display will show 12:00:00 UTC as the ETA .
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GLIDE
Glide can compute the horizontal distance (Dist) in
nautical miles, given the glide ratio (Rat) and descent
(Desc) in feet .
Problem:
An aircraft has a best glide ratio of 30:1 .
What is the maximum number of nautical miles
traveled while losing 2,000 feet?
Solution:
Press the key . Select the Glide
submenu . Press:
and tap enter for 30:1 Rat, then
and tap enter for 2000 FT Desc .
The answer is a distance of 9 .87 NM .
Glide can compute descent (Desc) in feet, given the
glide ratio (Rat) and horizontal distance (Dist) .
Problem:
How many feet will an aircraft sink in 15
nautical miles if the lift/drag ratio is 22:1?
Solution:
Press the key . Select the Glide
submenu . Press:
and tap enter for 22:1 Rat, then
and tap enter for 15 NM Dist .
The answer is 4,143 FT Desc .
Glide can compute the glide ratio (Rat) given the
horizontal distance (Dist) and the descent (Desc) .
Problem:
An aircraft has lost 2,000 feet in 9
nautical miles . What is the glide ratio for the
aircraft?
Solution:
Press the key . Select the Glide
submenu . Press:
and tap enter for 2000 FT Desc,
then and tap enter for 9 NM Dist .
The answer is a glide ratio of 27 .3:1 .
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CLIMB & DESCENT
By entering distance (Dist) and descent (Desc) you
can acquire angle of climb or descent (AoC/D) and
glide ratio (Rat) . You can also enter in ground speed
(GS) and get your rate of climb or descent (RoC/D) .
Note that Desc will work for both altitudes either
climbing or descending .
Problem:
An aircraft has lost 5,000 feet in 30
nautical miles . What is the angle of descent and
glide ratio for this aircraft?
Solution:
Press the key . Select the Climb &
Descent submenu . Press:
and tap enter for 30 NM Dist, then
and tap enter for 5000 FT Desc .
The answers are 166 .67 FT/NM AoC/D and
36 .5:1 Rat .
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