Which of the following statements is correct concerning the effect of turning errors on a direct reading compass ?
MCQ > aircraft
Which of the following is an occasion for carrying out a compass swing on a Direct Reading Compass ?
When is the magnetic compass most effective ?
When an aircraft on a westerly heading on northern hemisphere accelerates effect of acceleration error causes magnetic compass to Indicate a turn towards north. acceleration/deceleration errors are false compass indications of a swing to north or south during speed changes of airplane this error most pronounced when flying on a heading of east or west decreases when flying closer to a north or south heading in a direct north or south heading this error does not occur in northern hemisphere compass swings towards north during acceleration towards south during deceleration in southern hemisphere this error occurs other way round when speed stabilises error disappears learn this for northern hemisphere ands ! a cceleration gives apparent turn to n orth d eceleration gives apparent turn to s outh. 
Given true track 180°drift 8°rcompass heading 195°deviation 2° calculate variation Indicate a turn towards north. use this wonderful table those questions. 
Compass deviation defined as angle between Magnetic north compass north. learn composition of this table . 
Given true course 300° drift 8°r variation 10°w deviation 4° calculate compass heading Magnetic north compass north. use this wonderful table those questions. Question 159-8
Given true track 352° variation 11° w deviation 5° drift 10°r calculate compass heading Magnetic north compass north. img /com_en/com061 143 jpg use this wonderful table those questions. Question 159-9
Given true track 070°variation 30°wdeviation +1°drift 10°r calculate compass heading Magnetic north compass north. use this wonderful table those questions. Question 159-10
Deviation applied to magnetic heading gives Magnetic north compass north. Learn composition of this table img /com_en/com061 141 jpg . Question 159-11
Given true course from a to b = 090° tas = 460 kt w/v = 360/100kt average variation = 10°e deviation = 2° calculate compass heading and gs Magnetic north compass north. put 460 kt (tas) on center dot under true index set true course 090° on rotative scale under wind mark 360°/100 kt you read 12° right drift img /com_en/com061 198a jpg turn to set under true index true heading 078° (090° 12° drift) you now read a ground speed under wind mark of 450 kt img /com_en/com061 198b jpg your true heading 078° minus 10°e variation your magnetic heading 068° for compass heading add 2°w deviation 068° + 2° = 070°. Question 159-12
An island observed weather radar to be 15° to left the aircraft heading 120° m and magnetic variation 17°w what the true bearing of aircraft from island Magnetic north compass north. our magnetic heading 120° magnetic variation 17° west our true heading 120° 17° = 103° true bearing of island from aircraft 103° 15°= 088° true bearing of aircraft from island 088° 180° = 268°. Question 159-13
The main reason mounting detector unit of a remote reading compass in wingtip of an aeroplane To minimise amount of deviation caused aircraft magnetism electrical circuits. our magnetic heading 120° magnetic variation 17° west our true heading 120° 17° = 103° true bearing of island from aircraft 103° 15°= 088° true bearing of aircraft from island 088° 180° = 268°. Question 159-14
A ground feature was observed on a relative bearing of 315° and 3 minutes later on a relative bearing of 270° the wind calm aircraft gs 180 kt the minimum distance between aircraft and ground feature To minimise amount of deviation caused aircraft magnetism electrical circuits. we have an isosceles triangle in an isosceles triangle two sides are equal in length 3 minutes at 180 kt = 9 nm this question has been seen in february 2023 with a relative bearing of 225° instead of 315° the answer remains same aircraft flying south instead of north. Question 159-15
An island observed to be 15° to left the aircraft heading 120° m variation 17° w the bearing ° t from aircraft to island To minimise amount of deviation caused aircraft magnetism electrical circuits. our magnetic heading 120° magnetic variation 17° west our true heading 120° 17° = 103° true bearing of island from aircraft 103° 15°= 088°. Question 159-16
Lined up on runway 05 047° what should a direct reading compass must indicate To minimise amount of deviation caused aircraft magnetism electrical circuits. amc 24 (cs25/cs 23) after correction cumulative deviation on any heading should not exceed 10° (5° to left 5° to right) when lined up take off you have to check if indication within limits if you read 042° or 052° you are allowed to take off this serviceability test consists of comparing drc indication to another reference (e g other compass system or runway direction) pdaus87 what the true answer? i do in aviation exam it states answer 037 057 if you read 037° 057° accuracy 20° it's not correct (and safe!) this question also exists with an other statement the maximum permissible deviation errors a direct reading compass is right answer 10°. Question 159-17
Permanent magnetism in aircraft arises chiefly from Hammering the effect of earth's magnetic field whilst under construction. amc 24 (cs25/cs 23) after correction cumulative deviation on any heading should not exceed 10° (5° to left 5° to right) when lined up take off you have to check if indication within limits if you read 042° or 052° you are allowed to take off this serviceability test consists of comparing drc indication to another reference (e g other compass system or runway direction) pdaus87 what the true answer? i do in aviation exam it states answer 037 057 if you read 037° 057° accuracy 20° it's not correct (and safe!) this question also exists with an other statement the maximum permissible deviation errors a direct reading compass is right answer 10°. Question 159-18
The main reason usually mounting detector unit of a remote indicating compass in wingtip of an aeroplane to Reduce amount of deviation caused aircraft magnetism electrical circuits. the detector unit positioned in a part of aircraft least affected on board electrical fields (usually wing tip or tail fin where any aircraft generated magnetic disturbances are at a minimum). Question 159-19
Concerning direct reading magnetic compasses in northern hemisphere it can be said that On an easterly heading a longitudinal acceleration causes an apparent turn to north. Onus overshoot north undershoot south. Question 159-20
A negative westerly magnetic variation signifies that True north east of magnetic north. the minimum magnetic variation (declination) 0° the maximum magnetic variation (declination) 180°and this will be along a line between magnetic north pole the geographic north pole a west magnetic variation (declination) signifies that true north east of magnetic north. Question 159-21
In northern hemisphere during an acceleration in an easterly direction magnetic compass will indicate A decrease in heading. acceleration errors these are caused inertia on east west headings because centre of gravity of compasse under pivot point accelerating makes bulk of compass lag behind machine dispace centre of gravity aft of pivot point img /com_en/com061 350 jpg if you were just going north south all you would get extra dip but because you are going east or west north bit of compass pointing to side of aircraft the displaced centre of gravity not being vertically in line with pivot point goes towards north to create a couple that makes compass turn clockwise to read less than 90° during turn a deceleration has oppposite effect to south (in northern hemisphere) acceleration errors are maximum on east/west headings near magnetic poles nil on north/south headings at equator the watchword here ands northern hemisphere (accelerate north decelerate south) or sand southern hemisphere (south accelerate north decelerate) img /com_en/com061 77 jpg example in northern hemisphere flying east if you accelerate needle will deflect to nearest pole (north an easterly deviation) to south when decelerate during acceleration at take off on runway 18 example a compass in northern hemisphere would indicate no apparent turn during acceleraton at take off in an easterly direction a magnetic compass in northern hemisphere indicates an apparent turn north during acceleraton at take off in an westerly direction a magnetic compass in southern hemisphere indicates an apparent turn south. Question 159-22
Magnetic compass calibration carried out to reduce A decrease in heading. calibration means measurement of deviation of a compass installed in an aircraft 'compass deviation' the difference between magnetic north the direction in which compass pointing deviation are measured in degrees east (+) or west ( ) causes of deviation compass magnets influenced magnetic fields within aircraft fuselage electronic equipments engines. Question 159-23
One purpose of a compass calibration to reduce difference if any between Compass north magnetic north. calibration means measurement of deviation of a compass installed in an aircraft 'compass deviation' the difference between magnetic north the direction in which compass pointing deviation are measured in degrees east (+) or west ( ) causes of deviation compass magnets influenced magnetic fields within aircraft fuselage electronic equipments engines. Question 159-24
One purpose of compass calibration to determine deviation Compass north magnetic north. the deviation accurately ascertained on a number of headings a graph drawn which enables us to find deviation on any heading then a deviation card mounted near compass showing addition or subtraction required to correct deviation on various headings usually at intervals of 30° for intermediate readings pilot should be able to interpolate mentally with sufficient accuracy. Question 159-25
The force acting on needle of a direct reading compass varies Directly with horizontal component of earth's magnetic field. magnetic dip the angle between horizontal vertical forces acting on a compass needle toward nearer pole img /com_en/com061 110 jpg the force acting on compass needle directly proportional to horizontal component of earth's field inversely proportional to vertical component of earth's at magnetic poles earth's magnetic field perpendicular to earth's surface magnetic dip 90° at magnetic poles (a dip needle stands vertical). Question 159-26
If compass heading 265° variation 33° w and deviation 3°e what the true heading Directly with horizontal component of earth's magnetic field. use this wonderful table those questions. Question 159-27
In a remote indicating compass system amount of deviation caused aircraft magnetism and electrical circuits may be minimised Mounting detector unit (flux valve) in wingtip. use this wonderful table those questions. Question 159-28
Which of following statements about hard and soft iron in relation to magnetism correct Hard iron magnetism of a permanent nature soft iron of a non permanent nature. soft magnetic iron a type of iron that has lower carbon content this type of soft magnetic iron used to make electromagnets the low carbon content makes iron more efficient at quickly getting magnetized demagnetized the soft iron does not retain memory of magnetism that means there no magnetism left in soft iron as soon as magnetic field removed this called low hysteresis loss in science this makes soft iron best suitable making electromagnets a hard iron in contrast to soft iron retains magnetism permanently. Question 159-29
Which of following variables affect deviation 1 magnetic latitude2 aircraft heading3 aircraft altitude4 aircraft electronic equipment Hard iron magnetism of a permanent nature soft iron of a non permanent nature. soft magnetic iron a type of iron that has lower carbon content this type of soft magnetic iron used to make electromagnets the low carbon content makes iron more efficient at quickly getting magnetized demagnetized the soft iron does not retain memory of magnetism that means there no magnetism left in soft iron as soon as magnetic field removed this called low hysteresis loss in science this makes soft iron best suitable making electromagnets a hard iron in contrast to soft iron retains magnetism permanently. Question 159-30
An ndb located at position n55°26' w005°42' the variation at ndb 9°w the position of aircraft 56°00'n 010°00'w the variation at aircraft position 11°w the initial true track of great circle from aircraft position to ndb position 101 5° what the magnetic bearing of ndb from aircraft Hard iron magnetism of a permanent nature soft iron of a non permanent nature. true track from aircraft position to ndb position 101 5° the variation at aircraft position 11°w magnetic bearing of ndb from aircraft = 101 5° + 11° = 112 5° notice 'variation west magnetic best' thus '+' the variation. Question 159-31
Given compass heading = 233°true track = 256°drift angle = 10°rdeviation = 3°what the variation Hard iron magnetism of a permanent nature soft iron of a non permanent nature. img /com_en/com061 629 jpg use this wonderful table those questions. Question 159-32
Deviation on standby compass Dependent on heading of aircraft. img /com_en/com061 629 jpg use this wonderful table those questions. Question 159-33
Givent deviation table of a direct reading compass drc the desired true heading 155° the variation in area 10°w course 000 030 060 090 120 150 180 210 240 270 300 330steer 359 030 061 092 121 150 178 209 242 272 298 331what should be indication of direct reading compass drc Dependent on heading of aircraft. desired true heading 155° ==> magnetic heading to follow ? ==> compass heading to follow ? true heading 155° ==> magnetic heading 155° + 10° = 165° (variation 10°west so magnetic best therefore our true heading less than our magnetic heading) the correction on deviation table 150° 0°and 180° 2° at 165° (halfway) it will be 1° 165° + ( 1°) = 164°. Question 159-34
Direct reading compass drc deviation table course 000 030 060 090 120 150 180 210 240 270 300 330steer 359 030 061 092 121 150 178 209 242 272 298 331direct reading compass indicates a heading 242° magnetic variation in this aera 22°e the true aircraft heading Dependent on heading of aircraft. the heading reads on instrument a compass heading deviation table gives a compass heading of 242° a magnetic heading of 240° you now have to apply magnetic variation (22°e) to find true heading 240°+ 22° = 262° for information variation east magnetic least variation 22°east so magnetic least therefore our true heading greater than our magnetic heading. Question 159-35
During pre flight check serviceability of a direct reading standby compass indication can be compared preferably with 1 runway direction during line up2 main compass indication3 test vor indication4 an adf bearing5 an airborne weather radar bearingthe combination regrouping all correct statements Dependent on heading of aircraft. the heading reads on instrument a compass heading deviation table gives a compass heading of 242° a magnetic heading of 240° you now have to apply magnetic variation (22°e) to find true heading 240°+ 22° = 262° for information variation east magnetic least variation 22°east so magnetic least therefore our true heading greater than our magnetic heading. Question 159-36
Which statement true about direct reading compass drc Before take off drc should be checked comparing heading to runway direction. the heading reads on instrument a compass heading deviation table gives a compass heading of 242° a magnetic heading of 240° you now have to apply magnetic variation (22°e) to find true heading 240°+ 22° = 262° for information variation east magnetic least variation 22°east so magnetic least therefore our true heading greater than our magnetic heading. Question 159-37
When an aircraft flies into vicinity of one of magnetic poles why does magnetic compass becomes unreliable or even useless The horizontal component becomes so weak that directive force insufficient a reliable compass indication. diagrammatic representation of earth's magnetic field illustrating how field lines (represented arrows) intersect earth's surface how inclination angle (the angle formed between field lines the earth) varies with latitude at magnetic equator (the curving line across earth) field lines are parallel to earth's surface the field lines become progressively steeper as one travels north toward magnetic pole where field lines are directed straight down into earth the inclination angle 90° near magnetic pole horizontal component of earth's magnetic field too small to permit use of a magnetic compass. Question 159-38
A significant amount of ferrous material transported on a cargo flight which aircraft system s should be checked accuracy The direct reading magnetic compass (drmc). diagrammatic representation of earth's magnetic field illustrating how field lines (represented arrows) intersect earth's surface how inclination angle (the angle formed between field lines the earth) varies with latitude at magnetic equator (the curving line across earth) field lines are parallel to earth's surface the field lines become progressively steeper as one travels north toward magnetic pole where field lines are directed straight down into earth the inclination angle 90° near magnetic pole horizontal component of earth's magnetic field too small to permit use of a magnetic compass. Question 159-39
According to certification specifications large aeroplanes cs 25 standby compass instruments accuracy of magnetic heading indications after correction should be better than or equal to The direct reading magnetic compass (drmc). cs 25 1327 direction indicator (b) the magnetic direction indicator required cs 25 1303(a)(3) may not have a deviation after compensation in normal level flight greater than 10 degrees on any heading an accuracy of 10° or better when readings are 042° 052° when line up on runway 05 example if you read 037° 057° accuracy 20° it's not correct! this question also exists with statement the maximum permissible deviation errors a direct reading compass is answer 10°. Question 159-40
Which of following will probably not result in a deviation change on a drc Turning adf on in flight. cs 25 1327 direction indicator (b) the magnetic direction indicator required cs 25 1303(a)(3) may not have a deviation after compensation in normal level flight greater than 10 degrees on any heading an accuracy of 10° or better when readings are 042° 052° when line up on runway 05 example if you read 037° 057° accuracy 20° it's not correct! this question also exists with statement the maximum permissible deviation errors a direct reading compass is answer 10°.
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