Gyroscopic Systems Flashcards
What powers Gyro instruments in the plane?
Vacuum pump via the airplane engine
What instruments contain gyros?
Attitude indicator
Heading indicator
Turn coordinator/indicator
How does the vacuum system operate?
Pressure system spins the Gyro by drawing the stream of air against the rotor veins to spin the rotor at high speeds.
Usually between 4.5-5” Hg
What are two important principles of gyros?
Rigidity: prevents its axis of rotation, tilting as the earth rotates
Precession: causes an applied force to be felt, not at the point of application, but 90° from that point in the direction of rotation
How does a turn coordinator work?
Uses procession to indicate direction and approximate rate of return.
Gyros react by trying to move and reaction to force applied, thus moving the miniature plane in proportion to rate of turn.
Ball measures relative strength of force of gravity and force of a nurse and caused by turn.
What information does the turn coordinator provide?
Displays the rate of turn, rate of role and direction turn.
The ball in the tube indicates the quality of the turn.
Turn coordinator, quality of turn: what is slip?
Ball on the inside of turn; not enough rate of turn for the amount of bank
Turn coordinator, quality of turn: what is skid?
Ball to the outside of turn; too much rate of turn for the amount of bank
What is the source of power for the turn coordinator?
Typically it is electrically powered.
How does a heading indicator work?
Works on the principle of rigidity in space.
Rotor turns in a vertical plane, fixed to the rotor is a compass card.
Since rotor remains rigid in space, points on the card hold the same position in space relative to vertical plane.
What are the limitations of a heading indicator?
Limits are approximately 55° of pitch and 55° of bank.
If exceeded instrument tumbles or spills and is no longer accurate until you reset.
What type of errors does the heading indicator have?
Depends largely upon the condition of the instrument.
While Gyro is depending on rigidity in space, earth rotates in at a rate of 15° an hour
How does the attitude indicator work?
Attitude indicator is mounted on a horizontal plane and depends upon rigidity in space for operation.
Horizon bar represents the true horizon and is fixed to the gyro.
It remains in a horizontal plane as the plane is pitched or bank about it’s lateral or longitudinal axis, indicating the attitude of the airplane relative to the true horizon
What limitations does the attitude indicator have?
Bank limits are usually from 100° to 110°.
Pitch limits are usually from 60° to 70°.
If exceeded, instrument will tumble or spill and will give incorrect indications until restabalized.
Is the attitude indicator subject to errors?
Usually free from most errors, depending on instrument.
There may be a slight nose up indication during rapid acceleration and nose down indication during rapid deceleration.
Also possibility of small bank angle and pitch error after 180° turn
