02 Magnetism And Compasses Flashcards
ATPL GEN-NAV
In still air, you wish to fly a true heading of 315°. Variation is 4°W. Deviation is 2°E. What compass heading should you fly?
317°
One purpose of a compass calibration is to reduce the difference, if any, between:
compass north and magnetic north.
An aircraft is flying a Compass Heading of 124ºC. Compass Deviation = -3º, Magnetic Variation = 4ºW. What is the True Heading?
117ºT
C D M V T
124ºC -3º(W) 121ºM 4ºW 117ºT
Direct reading compass (DRC) deviation table is: Course: 000 030 060 090 120 150 180 210 240 270 300 330 Steer: 359 030 061 092 121 150 178 209 242 272 298 331 Direct reading compass indicates a heading 242°. Magnetic variation in this area is 22°E. The true aircraft heading is:
262°
Compass heading is 242º. This is the heading the aeroplane is steering, thus find the appropriate number on the “steer” line. The corresponding number on the “course” line is the magnetic heading.
Then correct for variation to find the true heading.
Steer: 242º
Course: 240º
Var.: E22º
TH: 262º
An aircraft is lined up on Runway 23, which is aligned with a magnetic bearing of 232°M. During pre-flight checks it is observed that the direct reading magnetic compass reads 243°M. What action should be taken by the flight crew in order to comply with maximum permissible deviation errors?
Cancel the flight and return to maintenance.
Complete the following statement regarding magnetic variation. The charted values of magnetic variation on earth normally change annually due to:
magnetic pole movement causing numerical values at all locations to increase or decrease
Given:
Compass Heading: 124°
Deviation: -3°
Variation: 4°W
Determine the True Heading.
117°
In a remote indicating compass system the amount of deviation caused by aircraft magnetism and electrical circuits may be minimised by:
mounting the detector unit (flux valve) in the wingtip.
A line drawn on a chart which joins all points where the value of magnetic variation is zero is called an:
agonic line
Given:
Variation: 7°W
Deviation: 4°E
If the aircraft is flying a compass heading of 270, the true and magnetic headings are:
267°(T); 274°(M)
An aircraft is lined up on Runway 24, which is aligned with a magnetic bearing of 242°M. In order to comply with maximum permissible deviation errors, the direct reading magnetic compass readings should be between:
232°- 252°
Which of the following is an occasion for carrying out a compass swing on a Direct Reading Compass?
After an aircraft has passed through a severe electrical storm, or has been struck by lightning
A direct reading compass should be swung when:
there is a large, and permanent, change in magnetic latitude
The deviation of a compass is described as +4. This means that:
The compass heading will have a lower number in degrees that the magnetic heading.
One purpose of compass calibration is to determine the deviation:
on any heading.
An aircraft is lined up on Runway 05, which is aligned with a magnetic bearing of 047°M. In order to comply with maximum permissible deviation errors, the direct reading magnetic compass readings should be between:
037° - 057°
An aircraft is purchased in New Zealand and taken to operate from Teeside, UK. The compass needs to be swung; this is because:
There was a large change of latitude
During pre-flight check, serviceability of a direct reading standby compass indication can be compared preferably with: 1 - runway direction during line-up 2 - main compass indication 3 - test VOR indication 4 - an ADF bearing 5 - an Airborne Weather Radar bearing The combination regrouping all the correct statements is:
1 and 2
Deviation on the standby compass is:
Dependent on the heading of the aircraft.
The outer marker of an ILS with a 3° glide slope is located 4.6 NM from the threshold. Assuming a glide slope height of 50 FT above the threshold, the approximate height of an aircraft passing the outer marker is:
1450 FT
On the CRP 5 put the 60/1 triangle at 3 for 3º glideslope.
4.6nm x 6080ft=27968ft so 28000. Find 28000 on the inside scale read opposite so 14.
1400ft plus 50ft above threshold = 1450ft
A transport aircraft is purchased in Australia and flown to Europe where it will be engaged in commercial operations with a base in Germany.
It will be necessary to perform a compass swing procedure because:
there was a large change of latitude.
The Earth can be considered as being a magnet with the:
BLUE pole near the North Pole of the Earth and the direction of the magnetic force pointing straight DOWN to the Earth’s surface.
At a specific location, the value of magnetic variation:
varies slowly over time
Direct reading compass (DRC) deviation table is: Course: 000 030 060 090 120 150 180 210 240 270 300 330 Steer: 359 030 061 092 121 150 178 209 242 272 298 331 You have to maintain the HEADING 155°(T). Magnetic variation is 10°W. The compass heading to follow is:
164°
The force acting on the needle of a direct reading compass varies:
directly with the horizontal component of the earth’s magnetic field
(The force action on the compass needle is directly proportional to the horizontal component of the Earth’s field (H) and inversely proportional to the vertical component of the Earth’s field (Z).(
What is the maximum tolerance allowed on the magnetic compass with correction applied on a (CS-25) large aeroplane?
10°
