Aircraft Instruments Pt 2. Flashcards
Vertical Speed Indicator-
This instrument indicated whether the aircraft is climbing, descending, or in level flight. Measures rate of pressure change.
Vertical Speed Indicator
An immediate indication of an increase or decrease in the aircraft’s rate of climb or descent
Trend Information
Shows a stabilized rate of change in altitude
Rate Information
State the instrument errors of a vertical speed indicator
- It inherently lags 6-9 seconds to stabilize which will inhibit accurate readings during turbulence or abrupt control movements
- A blocked static port will give a zero indication
The vertical speed indicator indicates the rate of climb or descent and is indicated in what?
feet per minute
Through this, the air leaves the instrument case slower than the diaphragm and allows for a stabilized indication of pressure change on the face of the instrument
Calibrated leak
As pressure drops, the diaphragm compresses, indicating a ________
climb
As the pressure increases, the diaphragm expands, indicating a _________
descent
Write down the pitot-static instruments table
check your ppt
This is also known as Gyroscopic Instruments
Vacuum Instruments
Where does the vacuum instruments get readings from?
Gyroscope
What are the vacuum instruments
- Attitude Indicator (AI)
- Turn Coordinator (TC)
- Heading Indicator (HI)
It is a spinning wheel or disc in which the axis of rotation is free to assume any orientation by itself
Gyroscope
What are the two principles the gyroscope operates based on?
Rigidity in Space
Gyroscopic Precession
The gyroscope remains in a fixed position in the plane in which it is spinning
Rigidity in Space
It is the tilting or turning of gyroscope in response to a deflective force
Gyroscopic Precession
When does the reaction to the gyroscopic precession occur?
Occurs at a point that is 90 degrees later in the direction of rotation
What are sources of power for vacuum instruments?
Vacuum- Driven Gyroscope
- Attitude Indicator
- Heading Indicator
Electrically Driven Gyroscope
-Turn Coordinator
This states if the amount of air in the gyroscopic instruments is accurate
Suction Gauge
What is the amount of suction in the suction gauge? and what does LOW and HIGH mean
4.5 - 5.5 inHg
Low = gyro is unstable and responds slowly
High = gyro spins too fast and be damaged
What was the attitude indicator originally called?
Artificial Horizon Indicator
It is a type of instrument used to reference the aircraft’s pitch and bank against an artificial horizon
Attitude Indicator
This senses pitch and roll movement
Attitude Indicator
The position of the airplane’s nose or wings in relation to the natural horizon
Attitude
The instrument gives immediate and direct indication of the aircraft’s orientation
Attitude Indicator
The attitude indicator operate on what principle?
Principle of rigidity in space
This instrument error for an attitude indicator shows that _______________ may cause a slight pitch up indication
Accelerations
This instrument error for an attitude indicator shows that _______________ may cause a slight pitch down indication
Decelerations
The attitude indicator should not bank more than _____ in taxi turns
5°
This is also called a directional gyro, used to determine aircraft direction to aid the pilot in navigation
Heading Indicator
It is fundamentally a mechanical instrument designed to facilitate the use of the magnetic compass
Heading Indicator
This is used to align the heading indicator with the magnetic compass
Adjustment knob
A heading indicator displays headings based on a ________________ with the final zero omitted
360° azimuth
State an instrument error for the heading indicator
- Friction: the heading indicator creeps or drifts from its set position. If the bearings are worn, dirty, or improperly lubricated, the drift may be excessive. The amount of drift depends largely upon the condition of the instrument
- Precession: The Earth rotates in space at a rate of 15° in 1 hour. Thus, the heading indicator may indicate as much as 15° error per every hour of operation
What are the two types of turn indicators?
- Turn-and-slip indicator
- Turn coordinator
This consists of a liquid-filled curved tube with a ball inside which states the coordination. This is used to determine quality of a turn.
Inclinometer
The gyro in this indicator rotates in the vertical plane corresponding to the aircraft’s longitudinal axis
Turn and slip indicator
Its gyro can sense both rate of roll and rate of turn
Turn Coordinator
Turn coordinators provide their readings with a _________________ mounted at a 30° angle.
Canted gyroscope
What does “2 MIN” printed in the turn coordinator?
Means standard rate turn held for 2 minutes would result in a 360 degree turn
It is also called Slip indicator. Used to depict aircraft yaw, which is the side-to-side movement of the aircraft’s nose
Inclinometer
This is backup components or instruments for when an instrument fails or malfunctions
Redundancy
What is the standard rate of turn?
3° per second
The rate of turn is too slow for the angle of the bank, and the ball moves to the inside of the turn
Slip
The rate of turn is too great for the angle of bank, and the ball moves to the outside of the turn
Skid
State an instrument check for turn coordinator
- During pre-flight, ensure that the inclinometer is full of fluid and has no air bubbles
- The ball should be resting at its lowest point
- When taxiing, the turn coordinator should indicate a turn in the correct direction while the ball moves opposite the direction of the turn
This displays airplane magnetic heading
Magnetic compass
It is a self contained unit which does not require eletrical or suction power
Magnetic compass
State the magnetic compass errors
- Magnetic Variation
- Deviation
- Magnetic Dip
- Acceleration/ Deceleration Errors
- Turning Errors
This is because of the angular difference between the true north and magnetic north
Magnetic Variation
Lines of equal variation
Isogonic line
Line of zero magnetic variation
Agonic line
This is caused by magnetic fields produced by metal and electrical accessories within the airplane
Deviation Error
These magnetic fields distort the Earth’s magnetic force, and cause the compass to swing away from the correct heading and points toward local magnetic fields
Deviation Error
This is the result of the vertical component of the Earth’s magnetic field
Magnetic Dip
This is responsible for compass errors during acceleration, deceleration, and turns
Magnetic Dip
They are most apparent when making shallow turns to or from a heading of North or South
Turning Errors
This error increases as the poles are neared and magnetic dip becomes more apparent
Turning Errors
What does UNOS stand for?
U- Undershoot (Compass Lags)
N- North
O- Overshoot
S- South
This is the effect of inertia and is evident on headings of East or West
Acceleration Error
If aircraft is accelerated on an East or West heading, the compass will indicate a turn to the _______
north
If the aircraft is decelerated on an East or West heading, the compass will indicate a turn to the _______
south
ANDS
A- Accelerate
N- North
D- Decelerate
S- South