Performing a ground speed check

T-45C TS INav-05

TACAN/VOR Navigation and Holding Procedures

c. When lead point is reached, turn to intercept

selected course

NOTE: The CDI may not have started to move at

lead point because it is not active until you are

within 10 degrees of the course.

d. Track inbound on radial

4. Performing a ground speed check

NOTE: For a reliable ground speed check, the DME

from the station should be greater than aircraft altitude

in thousands of feet.

EXAMPLE: Altitude is 30,000 ft (FL 300), so DME

should be 30 nm or greater.

a. Start timing when DME indicator displays a whole

number

b. After predetermined time (in minutes), check and

note DME

c. Determine distance flown and multiply that number

by multiplier corresponding to time flown

EXAMPLE: Your distance flown is 6 on the DME

indicator. The elapsed time is 1 minute, so 6 times

60 equals 360. Ground speed is 360 kts (6 nm/min

times 60 min/hr equals 360 nm/hr).

NOTE: Track either inbound or outbound on a given

radial when making a ground speed check.

NOTE: Every 1/10 nm equals 6 kts.

NOTE: Checking ground speed for more than 1

minute increases the accuracy of this method.

5. Proceeding direct between TACAN fixes (point-to-point)

a. Tune and identify station if not already done

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