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► The following values are given: Grid track: 192, Grid convergence: 48W, Variation: 10E, Deviation: 2W. Find: Magnetic heading when WCA is 9L:
Answer: MH 221
Grid Track = 192 GT
48W (true track "best') = 240 TT
WCA 9L = the true heading is 9° to the LEFT of 240 = 231 TH
VAR 10E (magnetic "least") = 221 MH
► Grivation is 56W when:
Answer: GH is 103° and MH is 159°
"Grivation west, magnetic best"
► Given: true track 070° variation 30°W deviation +1° drift 10°R. Calculate the compass heading?
Answer: 089°
True track = 070
10R drift means 10L WCA (or "heading will be to the LEFT of 070")
True heading = 060
Variation 30°W (magnetic best) = 60 + 30 = 90°
Deviation = +1° (+ = East so compass least) = 90 - 1 = 89°
► If the true HDG is 165° and the variation is -3, what is the magnetic heading?
Answer: Variation is negative (Westerly), therefore magnetic heading is 168°
Variation West = Magnetic Best
► If variation is expressed as Westerly, then:
Answer: True North is East of Magnetic North
For variation we look from MAGNETIC to TRUE, so variation West means that magnetic lies West of true (or true lies east of magnetic)
► The value of variation:
Answer: Has a maximum value of 180°
► The value of magnetic variation on a chart changes with time. This is due to:
Answer: Movement of the magnetic poles, which can cause either an increase or decrease
► Deviation is:
Answer: A correction to be added to compass heading to obtain magnetic heading
► The magnetic north pole seems to rotate around the geographical north pole. a rate of this movement is approximately:
Answer: 1° in 5 years
► Given true heading 066°, variation 4°W, drift angle 12°R, relative bearing to the station 070°. What is the true bearing of the aircraft from the station?
Answer: 316°
TH (66) + RB (70) = TB (136) TO station
Reciprocal = 316° FROM station
► The maximum difference in distance when proceeding along the great circle between two positions, in stead of the rhumb line, will occur:
Answer: On East-West tracks at high latitudes
Difference in distance (departure) = On East and West tracks
At higher latitudes, the meridians convergence towards the north/south pole so for the same distance (as at the equator for example), the difference in longitude will be much greater!
Answer: MH 221
Grid Track = 192 GT
48W (true track "best') = 240 TT
WCA 9L = the true heading is 9° to the LEFT of 240 = 231 TH
VAR 10E (magnetic "least") = 221 MH
► Grivation is 56W when:
Answer: GH is 103° and MH is 159°
"Grivation west, magnetic best"
► Given: true track 070° variation 30°W deviation +1° drift 10°R. Calculate the compass heading?
Answer: 089°
True track = 070
10R drift means 10L WCA (or "heading will be to the LEFT of 070")
True heading = 060
Variation 30°W (magnetic best) = 60 + 30 = 90°
Deviation = +1° (+ = East so compass least) = 90 - 1 = 89°
► If the true HDG is 165° and the variation is -3, what is the magnetic heading?
Answer: Variation is negative (Westerly), therefore magnetic heading is 168°
Variation West = Magnetic Best
► If variation is expressed as Westerly, then:
Answer: True North is East of Magnetic North
For variation we look from MAGNETIC to TRUE, so variation West means that magnetic lies West of true (or true lies east of magnetic)
► The value of variation:
Answer: Has a maximum value of 180°
► The value of magnetic variation on a chart changes with time. This is due to:
Answer: Movement of the magnetic poles, which can cause either an increase or decrease
► Deviation is:
Answer: A correction to be added to compass heading to obtain magnetic heading
► The magnetic north pole seems to rotate around the geographical north pole. a rate of this movement is approximately:
Answer: 1° in 5 years
► Given true heading 066°, variation 4°W, drift angle 12°R, relative bearing to the station 070°. What is the true bearing of the aircraft from the station?
Answer: 316°
TH (66) + RB (70) = TB (136) TO station
Reciprocal = 316° FROM station
► The maximum difference in distance when proceeding along the great circle between two positions, in stead of the rhumb line, will occur:
Answer: On East-West tracks at high latitudes
Difference in distance (departure) = On East and West tracks
At higher latitudes, the meridians convergence towards the north/south pole so for the same distance (as at the equator for example), the difference in longitude will be much greater!
