INS Flashcards
Errors of the DGI are:
Select one:
a. gimballing error, looping error, rolling error, rotor speed error, transport wander
b. gimballing error, random wander, apparent wander, rotor speed error, transport wander
c. acceleration error, turning error, altitude error, transport wander, rotor speed error
d. transport wander, apparent wander, latitude error, turning error, acceleration error
b. gimballing error, random wander, apparent wander, rotor speed error, transport wander
A directional gyro indicator is basically a:
Select one:
a. vertical axis earth gyro
b. vertical axis tied gyro
c. horizontal axis tied gyro
d. horizontal axis earth gyro
c. horizontal axis tied gyro
The maximum drift error sensed by an uncompensated DGI will be:
Select one:
a. 60° per hour
b. 45° per hour
c. 30° per hour
d. 15° per hour
d. 15° per hour
In an air driven directional gyro the air jets are attached to:
Select one:
a. the rotor axis
b. the instrument casing
c. the outer gimbal
d. the inner gimbal
c. the outer gimbal
Apparent wander may be corrected in a DGI by:
Select one:
a. correcting wander by means of air jets
b. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the same direction as apparent wander
c. causing the gyro to precess in a clockwise direction (in the Northern Hemisphere)
d. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the opposite direction to apparent wand
d. attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the opposite direction to apparent wander
What type of gyroscope is fitted to a direction indicator?
Select one:
a. vertical axis & 2 degrees of freedom
b. horizontal axis & 2 degrees of freedom
c. vertical axis & 1 degree of freedom
d. horizontal axis & 1 degree of freedom
b. horizontal axis & 2 degrees of freedom
The latitude nut of a directional indicator (DI) is on the ………. gimbal and causes the gyroscope to precess around its ………. axis.
The correct words to complete the above sentence are:
Select one:
a. outer, horizontal
b. inner, vertical
c. inner, horizontal
d. outer, vertical
b. inner, vertical
In a DGI what error is caused by the easterly or westerly aircraft movement over the earth?
Select one:
a. real wander
b. Earth rate
c. transport wander
d. latitude error
c. transport wander
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.
The correct words to complete the above sentence are:
Select one:
a. the yawing plane; air jets, wedge plate
b. the yawing plane; air jets, torque motor
c. the horizontal plane; air jets; wedge plate Incorrect
d. the vertical plane; air jets, torque motor
b. the yawing plane; air jets, torque motor
A directional gyro is valid only for a short period of time. The causes of this inaccuracy are:
- Earth rotation
- longitudinal accelerations
- a/c motion over the Earth
- mechanical defects
- gyro mass
The combination of correct statements is: Select one: a. all of them b. 1, 3 & 5 c. 1, 3 & 4 d. 1, 2 & 3
c. 1, 3 & 4
Does the DI (Directional Gyro Indicator) suffer from, Turning error and/or acceleration errors?
No
Total DGI error?
TD = Rw + Er + Ln + Tw
TW = easterly GS/60 x tan(lat) Er = -/+15 x sin(lat) LatNut = +/-15xsin(lat)
DGI
Drift due earth rate (ER) :
Northern hemisphere: -
Southernthern hemisphere: +
+/- 15 x sin(lat)
DGI
Drift due Latitude Nut (LN)
Northern hemisphere: +
Southernthern hemisphere: -
+/- 15 x sin(lat)
DGI
Drifte due Transport wander (TW) EAST:
Northern hemisphere: +
Southernthern hemisphere: -
TW = easterly GS/60 x tan(lat)
DGI
Drifte due Transport wander (TW) WEST:
Northern hemisphere: -
Southernthern hemisphere: +
TW = easterly GS/60 x tan(lat)
Acceleration during the take-off run causes the air driven artificial horizon to falsely indicate:
Select one:
a. the right wing going down due to pendulosity of the outer gimbal
b. the nose pitching up due to the action of the pendulous vanes
c. the right wing going down due to the action of the pendulous vanes
d. the nose pitching up due to pendulosity of the gyro housing
b. the nose pitching up due to the action of the pendulous vanes
When accelerating the electric artificial horizon:
Select one:
a. has a reduced roll error due to the pitch cut-out switch
b. has a reduced pitch error due to the roll cut-out switch
c. has a reduced pitch error due to the pitch cut-out switch
d. has a reduced roll error due to the roll cut-out switch
c. has a reduced pitch error due to the pitch cut-out switch
When turning through 90° at constant attitude and bank, a classic artificial horizon indicates:
Select one:
a. nose up and correct angle of bank
b. attitude and bank angle are correct
c. nose up and bank angle too high
d. nose up and bank angle too low
d. nose up and bank angle too low
An electrical artificial horizon employs ………. and ……….. to maintain its position in relation to ………..
Select the line of phrases given below that would complete the above statement correctly:
Select one:
a. mercury switches, torque motors, the local vertical
b. fast erect buttons, micro switches, local longitude
c. a precession circuit, a torque motor, azimuth
d. an erection chamber, pendulous vanes, space
a. mercury switches, torque motors, the local vertical
A gravity erector system corrects errors on a:
Select one:
a. turn co-ordinator
b. turn indicator
c. artificial horizon
d. DGI
c. artificial horizon
The air driven artificial horizon uses ………. gyroscope which is maintained ………. by means of ……….
The words which correctly complete the above sentence are:
Select one:
a. a free horizontal, case levelling
b. an Earth vertical, torque motors
c. an Earth vertical, pendulous vanes
d. a space vertical, torque motors
c. an Earth vertical, pendulous vanes
An artificial horizon has:
Select one:
a. 1 degree of freedom and a horizontal axis
b. 2 degrees of freedom and a vertical axis
c. 2 degrees of freedom and a horizontal axis
d. 1 degree of freedom and a vertical axis
b. 2 degrees of freedom and a vertical axis
A standby artificial horizon must have the following properties:
- a remote gyro
- its own power supply
- only to be used in emergency
- its own gyro
- one for each certified pilot
The combination regrouping all the correct statements is: Select one: a. 1, 2, 3, 4 & 5 b. 1, 3 & 5 c. 2, 3 & 4 d. 2 & 4
d. 2 & 4