AE Gyroscopic instruments Flashcards
Hvernig finnur þú earth rate (error due to earth’s rotation) fyrir 45°N ?
Hourly drift rate er þá 15*sin(45) = 10.6°.
Driftið er “to the right” held ég því í northern hemisphere er drift clockwise = to the right.
Í gyromagnetic compass, hvaðan er græjan að fá stefnuna?
Flux valve.
The pendulous type correction detector fitted to the gyromagnetic compass indicator provides ___ on the ___ axis.
Torque, sensitive.
Í hvað af þesu er rate gyro notað?
a) DGI b) Turn coordinator c) Artificial horizon
b) Turn co-ordinator.
In a gyro magnetic compass, does the torque motor get its information from the flux gate or amplifier?
Amplifier
Most likely reason for a gyro to precess
a) Force applied to the spinning rim in the same direction as the axis of rotation.
b) Force applied 90° to the axis of rotation.
a) Force applied to the spinning rim in the same direction as the axis of rotation.
Heading information is given by a gyro with __ degrees of freedom in the ___ axis
2 degrees of freedom in the horizontal axis.
The gyro axis of an electric artificial horizon is tied to the earth’s ____ by two mercury level switches and ___ torque motors
vertical, two
when in flight the needle and ball of a needle-and-ball indicator are on the right, the aircraft is turning right with too much ___.
bank.
Hvað gerist fyrir artificial horizon (air driven) í beygjum? Farðu með töfluna.
90° - apparent climb, under-indication of bank
180° - apparent climb, correct bank indication
270° apparent climb, over-indication of bank
360° - everything correct
Is an ADI (attitude indicator) electrical or vacuum driven?
Can be both
Nefndu fjóra errora sem geta gerst fyrir directional gyroscope.
Apparent wander due to earth rotation, apparent wander due to change of aircraft’s position, gimballing errors, mechanical malfunctions.
What is the most likely reason for a freely suspended gyro to precess? When a force is applied to the _____ in the same direction as the ____.
spinning rim, axis of rotation.
In a gyromagnetic compass, they gyro axis is maintained vertical/horizontal. It is servo-controlled in azimuth or free in azimuth?
It is maintained horizontal (hugsa það þannig að það skiptir máli upp á hvernig þú snýrð en það er aðalmálið) og servo-controlled þýðir væntanlega að þetta er drifið áfram af annari græju (t.d. flux valve).
The higher the airspeed is, the ___ the bank angle must be to turn at the standard rate.
higher
Er micro-electromechanical sensors technology notað til að nota attitude and heading reference systems (AHRS) ?
já
Following a 180° stabilized turn with a constant attitude and bank, the artificial horizon indicates what in pitch and banking?
too high pitch up and correct banking.
The gyroscope of a turn indicator has _ degree of freedom.
1
The spin axis of the turn indicator gyroscope is parallel to the ____ axis.
pitch
In a slaved directional gyro indicator the detection system of the local vertical feeds a levellin erection ____.
torque motor.
The indication of the directional gyro as an on-board instrument are valid only for a short period of time. The causes of this inaccuracy are:
Earth’s rotation
longitudinal acceleration
the aircraft’s motion over the surface of the earth
mechanical defects of the gyro
gyro’s weight
gimbal mount of the gyro rings.
Allt nema ekki longitudinal acceleration né heldur gyro’s weight.
A mechanical attitude director indicator (ADI) relies on a) electrical b) vacuum gyro?
Can be both.
How will the gyro axis drift in the N hemisphere?
Clockwise.. anti-clockwise in the S hemisphere.
With an air driven artificial horizon and you accelerate during take-off run, what will the instrument show?
False nose up indication
Ertu með speed hold í lateral flight path mode í autopilot?
Nei
Ertu með “localizer intercept and track” í lateral flight path mode í autopilot?
Já
Hvað kallast svona í autoflight system? “Continuous comparison between target and sensed value, computation and execution of required change, constant feedback about the effect of the manipulation.”
closed loop
Command bar type flight director; the horizontal/vertical bar is associated with the pitch channel.
horizontal
At 50 feet AGL during autoland, what happens to the glideslope signal?
it is disconnected.
What is the most basic function of an autopilot?
a) altitude hold
b) speed along track and wings horizontal
b) speed along track and wings horizontal
The basic modes of an autopilot consist of
a) controlling the path…
b) stabilizing the aircraft…
c) controlling the movement…
d) controlling the path…
b) stabilizing the aircraft…
ALT HOLD mode:
Parameters taken into account: Altitude ____, ___ attitude.
deviation, pitch
Flight director indicates the:
a) optimum instantaneous path to reach a selected radial.
b) optimum path at the moment it is entered to reach a selected radial.
a) optimum instantaneous path to reach a selected radial.
Er “pitch attitude hold” flight path mode?
Nei, þú myndir ekki velja það sem svar EN þetta er samt hluti af “ALT HOLD” mode.
Í gyro magnetic compass, hvaðan fær torque motor sínar upplýsingar?
Amplifier
Right turn while taxiing causes the a) indicator and the b) ball to go
a) right
b) left
Hvað heitir kerfið sem er notað til að búa til heading og reference systems?
Micro-Electromechanical systems (MEMS)
Ef þú ert að taka standard rate og vilt halda því og gefur inn afl, hvað þarftu að gera við bank angle?
Auka það.
Turning left but ball on the right: you are turning left, bank is too much/loo little?
too little
AHRS (Attitude Heading Reference System) miðað við mechanical gyroscope.. hvort kostar meira?
Mechanical gyroscope kostar meira.
Hvaða tvo undirflokka hefur Gyro Wander?
Real Wander og Apparent Wander
Hvaða undirflokka hefur real wander og apparent wander?
Real wander hefur engan undirflokk. Apparent wander skiptist í earth rate og transport wander
Hver er formúla earth rate?
Earth Rate = 15 × sine latitude °/hour
Earth rate is positive/negative in the northern hemisphere
negative
Some gyros measure angles, e.g. 10° of pitch, 5° of bank, 30° of heading change, etc. These are called _____ gyros. Others measure angular rate, e.g. a turn rate of 3° per second. These are called ___ gyros.
displacement, rate
Displacement gyros have _ gimbals and _ degrees of freedom
2, 2
DGI og artificial horizon eru dæmi um ___ gyro
displacement
What kind of gyro’s are used in the yaw dampers and rate of turn indicator?
Rate gyros
Rate gyro’s have _ degree of freedom and _ gimbal.
1, 1
Displacement gyros can be subdivided into ____ gyros or tied gyros
space
Er earth gyro a space gyro eða tied gyro?
tied gyro.
Dæmi um earth gyro er Artificial horizon. An earth gyro is one which is maintained vertical or horizontal with respect to local gravity.
Rigidity of a gyroscope depends on
a) weight, rate of precession, speed of rotation
b) mass, radius of gyration, speed of rotation
b) mass, radius of gyration, speed of rotation
A force is applied to deflect a gyroscope. If the rpm of the gyro is then doubled, the precession rate will:
a. remain as before
b. increase
c. decrease
d. cease altogether
c. decrease
Þetta skil ég illa.
Topple, á þetta við um real eða apparent wander?
bæði
A force applied to the ____ of a rotor is precessed through 90° in the direction of spin of the rotor.
spinning axis.
þú ýtir á hliðina á “dekkinu” (það er í sömu átt og spin axis), og svo ef þú vilt horfa á þetta út frá direction of spin of rotor (sem gæti t.d. bara verið áfram, t.d. bíll að keyra áfram)… þú ert þá augljósalega að ýta 90° miðað við þá átt.
Real wander of a gyro can be caused by:
a. asymmetrical friction at the spinning axis
b. rotation of the earth
c. increasing the rpm of the rotor
d. moving the gyro north or south of its present position
a. asymmetrical friction at the spinning axis
A gyro with only one degree of freedom is known as a:
a. tied gyro
b. earth gyro
c. space gyro
d. rate gyro
d. rate gyro
A perfectly balanced space gyro at the equator has its spin axis aligned with true north. After 6 hours the axis will be aligned with:
a. true east direction
b. true west direction
c. true north direction
d. true south direction
c. true north direction
Hér er trikkið að vita að space gyro snýr alltaf að sama staðnum væntanlega. Mögulega er það bara tied gyro’s sem breytast.
The main advantage of electric gyros are:
a) high RPM, only require low voltage DC, constant speed, sealed casing
b) high RPM, high moment of inertia, rapid build-up of speed, constant RPM
b) high RPM, high moment of inertia, rapid build-up of speed, constant RPM
A directional gyro indicator is basically a:
a. horizontal axis earth gyro
b. horizontal axis tied gyro
c. vertical axis earth gyro
d. vertical axis tied gyro
b. horizontal axis tied gyro
Skil horizontal en af hverju tied? Tied við norður?
Apparent drift may be corrected in a DGI by:
a. causing the gyro to precess in a clockwise direction (in the northern hemisphere)
b. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the same direction as apparent wander
c. correcting wander by means of air jets
d. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the opposite direction to apparent wander
d. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the opposite direction to apparent wander
Basicly til að leiðrétta DGI þá setur þú vigt á inner gimbal sem heldur við.
An air driven DGI is corrected for apparent wander at 56°N. If the aircraft is maintaining constant DGI readings:
a. when flying north from 56°N the true heading of the aircraft will decrease
b. when flying east from 56°N the true heading will decrease
c. when flying south from 56°N the true heading will decrease
d. when flying west from 56°N the true heading will increase
c. when flying south from 56°N the true heading will decrease
Meikar sens. Skekkjan er meiri þeim mun norðar sem þú ferð, er þá ekki bara stefnan líka að minnka þegar þú flýgur suður, þeas minni skekkja minni stefna.
The formula used to calculate apparent wander of a directional gyro in the northern hemisphere is:
a. +15 sine latitude in degrees for the time of running
b. +15 sine latitude in degrees per hour
c. -15 sine latitude in degrees per hour
d. 15 sine latitude in degrees per hour increasing
c. -15 sine latitude in degrees per hour
Errors of the directional gyro are:
a) gimballing error, random wander, apparent wander, rotor speed error, transport wander
b) transport wander, apparent wander, latitude error, turning error, acceleration error
b) transport wander, apparent wander, latitude error, turning error, acceleration error
Ég klikkaði á að það er latitude-, acceleration- og turning error í DGI
The spin axis of a directional gyro is maintained in ……. by means of …… in an air driven gyro and by means of a ……. in an electrically driven gyro.
a. the horizontal plane; air jets; wedge plate
b. the vertical plane; air jets; torque motor
c. the yawing plane; air jets; torque motor
d. the yawing plane; air jets; wedge plate
c. the yawing plane; air jets; torque motor
In an air driven directional gyro the air jets are attached to:
a. the inner gimbal
b. the outer gimbal
c. the instrument casing
d. the rotor axis
b. the outer gimbal
The limits of pitch and roll for a modern directional gyro are respectively:
a. 55° and 85°
b. 85° and 55°
c. 55° and 55°
d. 85° and 85°
d. 85° and 85°
Gimballing error:
a. will disappear after a turn is completed
b. will remain until the gyro is reset
c. will only occur during a 360° turn
d. will be zero on only two headings during a 360° turn
a. will disappear after a turn is completed
An artificial horizon uses an ___ gyro
earth
during a take off run the AH will show a nose up and a left/right wing low
right wing low
False nose-up attitude displayed on air driven artificial horizon during the take-off run is caused by:
the lag of the lateral ________.
pendulous vanes
The rotor axis of an electrical horizon is tied to the earth’s vertical by:
a. four pendulous vanes
b. the roll cut-out
c. the low centre of gravity of the rotor housing
d. two mercury level switches and two torque motors
d. two mercury level switches and two torque motors
False right wing low attitude shown on an air driven artificial horizon during an acceleration is caused by:
a. the lag of the base of the rotor housing
b. the logitudinal pendulous vanes
c. the roll cut-out
d. high rotor speed
a. the lag of the base of the rotor housing
Kannski ágætt að reyna að muna bara að right wing low í take off er vegna laggs.
Inside an artificial horizon:
a. the inner gimbal ring is pivoted laterally inside the outer gimbal ring and the outer gimbal ring is pivoted longitudinally inside the case
b. the inner gimbal ring is tied to the vertical by a control system
a. the inner gimbal ring is pivoted laterally inside the outer gimbal ring and the outer gimbal ring is pivoted longitudinally inside the case
When an adjustable aircraft datum is fitted to an artificial horizon in light aircraft:
a. it should be checked at regular intervals
b. it should be set to the central position and left there
b. it should be set to the central position and left there
An electrically driven artificial horizon has less errors during the take-off run because:
a. it is less pendulous, has a higher rotor speed and a linear acceleration cut-out
b. the mercury level switches are more sensitive than the pendulous vanes fitted to air driven types
a. it is less pendulous, has a higher rotor speed and a linear acceleration cut-out
The radius of a turn at rate 1, and TAS 360 kt is…
Auðveld en ónákvæm aðferð:
360*1% = 3.6 (diameter)
3.6/2 = 1.8 NM
(Rétt svar var 2 NM og var þetta lang nálægasta svarið).
If the filter of the air driven rate of turn indicator becomes partially blocked:
a. the aircraft will turn faster than indicated
b. the instrument will over-read
c. the rate of turn indicated will be unaffected
d. the radius of the turn will decrease
a. the aircraft will turn faster than indicated
Les þannig í þetta að ef það er ekki að komast nóg loft að tækinu þá under-readar það (það er ekki valmöguleiki í svörum EN til þess að ná ákveðnu turn þá beygir flugmaður bara meira og þaðan kemur svarið)?
When the pointer of a rate of turn indicator shows a steady rate of turn:
c. the spring is providing a force which produces a precession equal to the rate of turn (in the opposite direction)
d. the spring is providing a force which produces a precession equal to the rate of turn (in the correct direction)
d. the spring is providing a force which produces a precession equal to the rate of turn (in the correct direction)
The gyro in a rate of turn indicator has higher/lower operating speed than the gyros used in other instruments because…
lower, a higher rigidity is not required.
When the pointer of a rate of turn indicator shows a steady rate of turn the spring is providing a force which produces a precession equal to the ____.
rate of turn
Í turn coordinator þá er “flugvélin” í mælinum með vinstri væng við strikið (vinstri beygja), hvað er hún að beygja margar gráður á sekúndu?
3°
A turn coordinator has __ gimbal ring/s pivoted longitudinally/latitudinally
1, longitudinally
