Wind and Magnetic Variation

Question 1

True Course (TC)

Answer 1

the proposed flight path measured clockwise from True North.

Question 2

Drift Correction (DC)

Answer 2

the correction applied to prevent drifting off course. DC not applied when headwind, tailwind.

(1) If the drift correction is to the left, it is subtracted from the TC.
(2) If the drift correction is to the right, it is added to the TC.

Question 3

True Heading (TH)

Answer 3

the angle measured clockwise from True North to the nose of the aircraft. It is the sum of TC +/- DC.

Question 4

Track (TR)

Answer 4

the actual flight path over the ground measured clockwise from True North (measured in same manner as TC).

Question 5

Drift Angle (DA)

Answer 5

the difference between TH and TR.

Question 6

When does TR=TC Conditions

Answer 6

• No Wind Condition
• Headwind Condition
• Tailwind Condition
• DC is correct.

Question 7

Ground Speed (GS)

Answer 7

Speed of the A/C over the ground
GS = TAS +/- wind speed
Used to calculate time required to fly a certain distance

Question 8

Magnetic Variation

Answer 8

Angular difference between true north (TN) and magnetic north (MN)

Question 9

Agonic Line

Answer 9

A line connecting points of zero degree variation

•Only one agonic line in the U.S.

Question 10

Isogonic Lines

Answer 10

Lines connecting points of equal magnetic variation

Question 11

Magnetic Heading (MH)

Answer 11

Measured from magnetic north clockwise to the nose of the A/C

Question 12

Easterly Variation

Answer 12

Compass needle points east of TN and is subtracted.

•“East is least.”

Question 13

Westerly Variation

Answer 13

Compass needle points west of TN and is added.

•“West is best.”

Question 14

Applying Variation

Answer 14

Find midpoint of TC.
•Apply nearest whole degree of variation.
•TC +/- DC = TH +/- VAR = MH

Question 15

Tail number for planning

Answer 15

R for army

Last 5 numbers of tail number