Question 188-1 : Consider the following statements on sunset ? [ Question security ]

Question 188-2 : Atmospheric refraction ?

Causes the sunrise to occur earlier and the sunset to occur later.

Question 188-3 : Consider the following statements on sunrise and sunset ?

At equator sunrise and sunset occur at quite regular times throughout the year.

Question 188-4 : 'true north' is ?

The direction along any meridian toward the true north pole.

Question 188-5 : In international aviation the following units shall be used for horizontal distance ?

Metres kilometres and nautical miles.

Question 188-6 : When dealing with heights and altitudes in international aviation we use the following units ?

Metre and feet.

Question 188-7 : 'kilometre' is defined as ?

A 110000 part of the meridian length from equator to the pole.

Question 188-8 : How long is 25 kilometres at 60°n ?

135 nautical mile.

Question 188-9 : Position a 50°000'n 138°300'w st a = utc 9 hposition b 50°000'n 175°450'e st b = utc + 12 hthe ground distance between a and b is 1736 nmon 4 february at 08 00 st a an aircraft is exactly above a at the moment the aircraft arrives at position b the air distance between a and b is 1636 nm the ?

09 00 st b 0502.

1st nothing to do with coordinates 2nd select the required facts at point a 08 00st 04th feb a 9h b +12ha >b 1736nm ground a >b 1636nm air wind 25ktst time at b 3rd calculate ground air distance 100nmuse logic 100nm25kt = 4h is the flight time at point a 08 00st +9h > 17 00utc is the time at departureat point b 17 00utc +12h > 05 00st is the time at departure but 05th feb the aircraft arrives 4h later soat b 05 00st +4h >09 00st 5th feb

Question 188-10 : Estimated time of departure a 15°150'n 072°060'w on 12 march is 01 00 st st = utc 5 h estimated time of arrival b 55°180'n 005°450'e 16 15 st on the same date st = utc + 1 h according to the jeppesen table sunset at b occurs at 18 57calculate the flight time from a to b and the time between arrival ?

09h15m and 02h42m.

Question 188-11 : What is meant by the term 'polar circle' ?

It is the parallel at the lowest latitude at which an observer can see the sun for 24 hours above the horizon.

Question 188-12 : Grivation is 56w when ?

Gh is 103° and mh is 159°.

Grivation = convergence + variationwesterly grivation = negative valueeasterly grivation = positive value just like variation grid heading = magnetic heading ± grivationgrid heading = magnetic heading w grivation or + e grivation 103° gh = 159° mh 56° grivation

Question 188-13 : The term 'ellipsoid' may be used to describe ?

The shape of the earth.

Question 188-14 : By 'ecliptic' is meant ?

The apparent yearly path of the sun around the earth.

Question 188-15 : Given ils glide path angle = 35° ground speed = 150 ktwhat is the approximate rate of descent ?

875 ftmin.

1 in 60 rule is a rule of thumb 35 x 150 x 100 60 = 875 ftmin

Question 188-16 : For a given track the following data is provided wind component = +45 ktdrift angle = 15° lefttrue air speed tas = 240 ktwhat is the wind component on the reverse track ?

65 kt.

Since the initial wind component is +45 knots on the original track the reverse track will have the wind component as 45 knots

Question 188-17 : The duration of civil twilight is the time ?

Between sunset and when the centre of the sun is 6° below the celestial horizon.

Question 188-18 : An aircraft is over position ho 55°30'n 060°15'w where yyr vor 53°30'n 060°15'w can be receivedthe magnetic variation is 31°w at ho and 28°w at yyr what is the radial from yyr ?

028°.

Ho postion and yyr vor are on the same meridian 060°15'w spaced by 2° of latitudeho position is located north of yyrvariation is applied at the vor at the position or the aircraft for a ndb variation west magnetic best aircraft is on the radial 028° 360° + 28°w from the yyr vor

Question 188-19 : An aircraft in the northern hemisphere is making an accurate rate one turn to the right if the initial heading was 135° after 30 seconds the direct reading magnetic compass should read ?

More than 225°.

In case of a turning speed of 3° per second 2 minutes bend or rate one turn the following rules are to be observed to a course north the turn will be ended when the compass indicates 30° less than north undershoot to a course south the turn will be ended when the compass indicates 30° past south overshoot to a course east or west the turn will be ended when the compass indicates the desired course to a course between east or west and north or south an undershoot or overshoot between 30° and 0° is used depending on whether the desired course is closer or less close to the north or southgeneral rule of thumb never see the northever see the southfor 30 seconds will turn through 90° and the aircraft should be on a heading of 135° + 90° = 225°the compass will over read when turning through south in the northern hemisphere and read more than 225°

Question 188-20 : When accelerating on a westerly heading in the northern hemisphere the compass card of a direct reading magnetic compass will turn ?

Anti clockwise giving an apparent turn towards the north.

Cmarzocchini westerly mean to the west the correct answer should be clockwise to the north if your direct reading magnetic compass indicates a turn to the north when on a westerley heading it turns anti clockwise because your heading on the compass will increase com encom061 70ajpgif your heading increases from 270° to 300° while accelerating the 270° moves anti clockwise and the 300° will replace it com encom061 70bjpgit is even more understable on a vertical card compass

Question 188-21 : A ground feature appears 30° to the left of the centre line of the crt of an airborne weather radar if the heading of the aircraft is 355° m and the magnetic variation is 15° east the true bearing of the aircraft from the feature is ?

160°.

If we were in an area with no magnetic variation our magnetic heading and our true heading will be 355°in that case the bearing of the ground feature will be 355° 30° = 325° and from the ground feature our aircraft bearing will be 325° 180° = 145° but magnetic variation is 15° east thus our magnetic heading is 355° magnetic variation is 15° east our true heading is 355°+15° = 010°010° 30°= 340°340° 180° = 160°

Question 188-22 : When decelerating on a westerly heading in the northern hemisphere the compass card of a direct reading magnetic compass will turn ?

Clockwise giving an apparent turn toward the south.

Acceleration errors these are caused by inertia on east west headingsbecause the centre of gravity of the compasse is under the pivot point accelerating makes the bulk of the compass lag behind the machine and dispace the centre of gravity aft of the pivot point com encom061 350jpgif you were just going north south all you would get is extra dip but because you are going east or west the north bit of the compass is pointing to the side of the aircraft and the displaced centre of gravity not being vertically in line with the pivot point goes towards north to create a couple that makes the compass turn clockwise to read less than 90° during the turn a deceleration has the oppposite effect to the south in the northern hemisphere acceleration errors are maximum on eastwest headings and near the magnetic poles and nil on northsouth headings and at the equatorthe watchword here is ands for northern hemisphere accelerate north decelerate south or sand for southern hemisphere south accelerate north decelerate com encom061 77jpgexample in the northern hemisphere flying east if you accelerate the needle will deflect to the nearest pole north for an easterly deviation and to the south when decelerate during deceleration after landing on runway 18 for example a compass in the northern hemisphere would indicate no apparent turn during deceleraton after landing in an easterly direction a magnetic compass in the northern hemisphere indicates an apparent turn south during deceleraton after landing in an westerly direction a magnetic compass in the southern hemisphere indicates an apparent turn north

Question 188-23 : When turning right from 330° c to 040° c in the northern hemisphere the reading of a direct reading magnetic compass will ?

Under indicate the turn and liquid swirl will increase the effect.

For turning errors northern hemisphere unos underturnunder read through north overturnover read through southsouthern hemisphere onus overturnover read through north underturnunder read through south

Question 188-24 : When accelerating on an easterly heading in the northern hemisphere the compass card of a direct reading magnetic compass will turn ?

Clockwise giving an apparent turn toward the north.

Acceleration errors these are caused by inertia on east west headingsbecause the centre of gravity of the compasse is under the pivot point accelerating makes the bulk of the compass lag behind the machine and dispace the centre of gravity aft of the pivot point com encom061 350jpgif you were just going north south all you would get is extra dip but because you are going east or west the north bit of the compass is pointing to the side of the aircraft and the displaced centre of gravity not being vertically in line with the pivot point goes towards north to create a couple that makes the compass turn clockwise to read less than 90° during the turn a deceleration has the oppposite effect to the south in the northern hemisphere acceleration errors are maximum on eastwest headings and near the magnetic poles and nil on northsouth headings and at the equatorthe watchword here is ands for northern hemisphere accelerate north decelerate south or sand for southern hemisphere south accelerate north decelerate com encom061 77jpgexample in the northern hemisphere flying east if you accelerate the needle will deflect to the nearest pole north for an easterly deviation and to the south when decelerate during deceleration after landing on runway 18 for example a compass in the northern hemisphere would indicate no apparent turn during deceleraton after landing in an easterly direction a magnetic compass in the northern hemisphere indicates an apparent turn south during deceleraton after landing in an westerly direction a magnetic compass in the southern hemisphere indicates an apparent turn north

Question 188-25 : A direct reading compass should be swung when ?

There is a large and permanent change in magnetic latitude.

A compass swing should be done on installation of the compasse in the first place as per maintenance schedules whenever there is any doubt about accuracy after a shock to the airframe or a lightning strike if the aircraft has been left standing for some time or has moved to a significantly different latitude if there is a large and permanent change in magnetic latitude angle of dip if a major component or electrical installation has changedaugust 2020 this question also exists with the right answer a period of 12 months has passed during which the aircraft has remained stationary on the ground

Question 188-26 : The direct reading magnetic compass is made aperiodic dead beat by ?

Keeping the magnetic assembly mass close to the compass point and by using damping wires.

Aperiodicity the ability to settle quickly after a disturbance without overshooting or oscillating which is helped by the transparent suspension liquid and a wire spider assembly two magnets keep the mass of the assembly near the pivot reducing inertia light alloys reduce inertia even more thus the mass of the assembly is kept close to the compass point and damping wires are used

Question 188-27 : Given true track is 348° drift 17° left variation 32°w deviation 4°ewhat is the compass heading ?

033°.

1429use this wonderful table for those questions

Question 188-28 : Which of the following statements is correct concerning the effect of turning errors on a direct reading compass ?

Turning errors are greatest on northsouth headings and are greatest at high latitudes.

Turning errors are caused by the dip of the compass needle which increases with latitudeturning errors are greatest on northsouth headings and they are zero when turning on eastwest headings

Question 188-29 : 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 compass swing should be done on installation of the compasse in the first place as per maintenance schedules whenever there is any doubt about accuracy after a shock to the airframe or a lightning strike if the aircraft has been left standing for some time or has moved to a significantly different latitude if there is a large and permanent change in magnetic latitude angle of dip if a major component or electrical installation has changed

Question 188-30 : When is the magnetic compass most effective ?

About midway between the magnetic poles.

1430a direct reading compass has a pivoted magnet that is free to aligne itself with the horizontal component of the earth's magnetic field 1945the compass is pendulous and symmetrical and will sit level if there is no magnetic field or if the field is horizontal with no vertical component of the earth's magnetic force as on the magnetic equator magnetic compass is the most effective about midway between the magnetic poles

Question 188-31 : When an aircraft on a westerly heading on the northern hemisphere accelerates the effect of the acceleration error causes the magnetic compass to ?

Indicate a turn towards the north.

Accelerationdeceleration errors are false compass indications of a swing to the north or south during speed changes of the airplane this error is most pronounced when flying on a heading of east or west and decreases when flying closer to a north or south heading in a direct north or south heading this error does not occurin the northern hemisphere the compass swings towards the north during acceleration and towards the south during deceleration in the southern hemisphere this error occurs the other way round when the speed stabilises the error disappearslearn this for northern hemisphere ands a cceleration gives apparent turn to n orth d eceleration gives apparent turn to s outh

Question 188-32 : Given true track 180°drift 8°rcompass heading 195°deviation 2°calculate the variation ?

21°w.

1437use this wonderful table for those questions

Question 188-33 : Compass deviation is defined as the angle between ?

Magnetic north and compass north.

Learn the composition of this table 1438

Question 188-34 : Given true course 300° drift 8°r variation 10°w deviation 4°calculate the compass heading ?

306°.

1439use this wonderful table for those questions

Question 188-35 : Given true track 352° variation 11° w deviation is 5° drift 10°rcalculate the compass heading ?

358°.

com encom061 143jpguse this wonderful table for those questions

Question 188-36 : Given true track 070°variation 30°wdeviation +1°drift 10°rcalculate the compass heading ?

089°.

1443use this wonderful table for those questions

Question 188-37 : Deviation applied to magnetic heading gives ?

Compass heading.

Learn the composition of this table com encom061 141jpg

Question 188-38 : Given true course from a to b = 090° tas = 460 kt wv = 360100kt average variation = 10°e deviation = 2°calculate the compass heading and gs ?

070° 450 kt.

Put 460 kt tas on center dot under true index set true course 090° on the rotative scale under the wind mark 360°100 kt you read 12° right drift com encom061 198ajpgturn to set under true index the true heading 078° 090° 12° drift you now read a ground speed under the wind mark of 450 kt com encom061 198bjpgyour true heading is 078° minus 10°e variation your magnetic heading is 068°for compass heading add 2°w deviation 068° + 2° = 070°

Question 188-39 : An island is observed by weather radar to be 15° to the left the aircraft heading is 120° m and the magnetic variation 17°w what is the true bearing of the aircraft from the island ?

268°.

Our magnetic heading is 120° magnetic variation is 17° west our true heading is 120° 17° = 103°true bearing of the island from the aircraft 103° 15°= 088°true bearing of the aircraft from the island 088° 180° = 268°

Question 188-40 : The main reason for mounting the detector unit of a remote reading compass in the wingtip of an aeroplane is ?

To minimise the amount of deviation caused by aircraft magnetism and electrical circuits.