Navigation
404-04
Ground School
CI Pesto
Topics of Discussion Today
• Time, Speed, and
Distance Calculations
• Solving TVMDC
Questions
• 1 in 60 Rule
• E6B Calculations of the
circular side
Time, Speed, Distance
• Speed, Time and Distance are related by
the equation:
Speed = Distance
Time
-Given any of the two variables, the other can be
found using this equation
Questions!
eed = Distance
Speed = 65 KM
Time
0.5 Hrs
Speed = 130 KM/Hr
*Note: Times need to be
converted into hours
More Questions!
me = Distance
Time = 200 Km
Time = 2 Hrs
Speed
100 km/Hr
Questions Cont.
Distance = Speed × Time
Distance = 50 Km/Hr × 3 Hrs
Distance = 150 Km
Speed Conversions
• Knots to MPH Multiply by 1.15
• MPH to Knots Divide by 1.15
• KPH to Knots Multiply by 0.54
• KPH to MPH
Multiply by 0.62
Time Conversions
• Hours to Minutes
Multiply by 60
• Minutes to Hours
Divide by 60
Time Conversion Q’s
Hours
Minutes
1 hr
270 mins
3.25 hrs
45 mins
Time in Flight
• To find the time in flight, divide the
distance by the ground speed.
The time to fly 120NM at a ground speed of 80 knots
is:
120 ÷ 80 = 1.5 hrs (1.5 hrs × 60 = 90 mins) 1 hr and
30 mins
Distance
• To find the distance flown in a given time,
multiply groundspeed by time.
The distance flown in 1 hr. 45 min. at a ground speed
of 120 knots is:
120 × 1.75 = 210 NM (1hr 45min = 105 min ÷ 60 =
1.75hrs)
Ground Speed
• To find the ground speed, divide the
distance flown by the time.
An airplane flies 270 NM in 3 hrs.
The ground speed is 270 ÷ 3 = 90 knots
Who Remembers
TVMDC?
TVMDC
• True Heading
• Variation
• Magnetic Heading
• Deviation
• Compass Heading
Or:
TV
MAKES
DUMB
CADETS
Useful or No?
• Why?
Finding Magnetic Heading
• Use your True Heading and Variation to
find your Magnetic Heading
This is important because Variation can cause a
big difference between the direction you want to
go, and the direction that you actually go!
Examples
True Heading
Variation
165∘
5∘ East
280∘
4∘ West
15∘
8∘ West
88∘
16∘ East
Magnetic
Heading
Finding Compass Heading
• Using your Magnetic Heading and
Deviation to find your Compass Heading
We do this because there are errors in the compass
due to manufacturing, age, friction etc. that may
cause the compass to not point exactly the way you
want to go
Examples
Magnetic
Heading
Deviation
95∘
4∘ West
180∘
8∘ East
360∘
1∘ West
278∘
12∘ East
Compass
Heading
All Together Now!
True
Heading
Variation
Magnetic
Compass
Deviation
Heading
Heading
180∘
3∘ East
4∘ West
270∘
6∘ West
2∘ West
10∘
5∘ East
7∘ East
145∘
4∘ West
8∘ East
The “One in Sixty” Rule
• An error in the track of one degree will
cause an error in position of about one
mile in a distance of 60 miles.
Example:
3 degrees off track will cause an aircraft to be 3
miles out to the side.
The E6B (Flight Computer)
• For your Entrance Exam, you wont have
to know the wind side of the E6B, only
the Circular Side
• This is the side that can be used to
quickly work out conversions with out the
use of a calculator or paper and pen
The E6B Workings
• The outside ring is distance and velocity
• The inside ring is time
All calculations can be done without using the flight
computer by using the following formula:
V =
D
V-velocity
T
D-distance
T-time
The E6B Cont.
• The inner circle is made to rotate so you
can line up the numbers in your equation
to find the answer
• The formulas and instructions are written
on the inner circle for you if you forget
E6B Cont.
Velocity
• To find Velocity, you move your inner
circle so that your time is under your
distance. The velocity will then be
indicated over the black arrow at the “60
marker”
E6B Cont.
Time
• Likewise, if you are looking for time, you
move the black triangle under your
velocity, and find your distance on the
outer circle. Your time will be on the inner
circle underneath the distance
E6B Cont.
Distance
• To find the distance, move the black
triangle under your velocity and use your
time on the inner circle to show the
distance on the outer circle shown above
the time.
Review
Velocity
Distance
70 MPH
21 Mi
110 MPH
11 min
40 Mi
210 MPH
180 MPH
Time
30 min
1 hr 12 min
30 Mi
And Thats It!
Best of Luck on the Test!
~Questions~