11.5.1 - Instrument System Flashcards
(28 cards)
In an unpressurised aircraft (cessna), the Alternate static source valve can be taken from the ______
cockpit
What does the Auxilliary pitot tube feed ?
Auto pilot
yaw dampers
overspeed warning system
flight recorded
flight directors
cabin diff. pressure
__________ converts pitot or static pressure into digital output signal through ________ databus
ADM (Air Data Module)
ARINC 429
In an altimeter, the bellows are designed with corrugations that allow ____________________
with a change in altitude
the expansion to be linear
What baro setting (QNH,QFE or QNE) are aeronautical charts usually set to?
QNH
What is the maximum altitude that a radio altimeter can kick in from?
2500 ft
__________ minimises static error
servo altimeter
Name the types of errors associated with altimeters (6)
- Scale Error
- Hysteresis
- After effect
- Friction
- Case Leak
- Barometric scale error
What is the difference between the VSI and altimeter
VSI has a pinhole in it which allows an accurately calibrated leak
An IVSI (Instantaneous Vertical Speed Indicator) has a _______
pump
The __________ is used for the power setting of the engines
TAT (Total air temperature probe)
Aircraft fly at about _____ Mach
0.85
Indications on an airspeed indicator are for the following:
Structural limit
Aerodynamic limit
Structural limit - Fixed red line (vmo)
Aerodynamic limit - Red barber pole (mmo)
As temperature decreases
The speed of sound ______
decreases
Vertical gyro =
Horizontal gyro =
Vertical gyro = attitude gyro = (pitch and roll)
Horizontal gyro = directional gyro ( yaw)
What does the Cage or ‘‘Caging’’ knob of a attitude indicator do?
Resets the gyro / attitude position
Levels it
_______ motors are used to keep gyros rotating
electric
The erection control applies for the first 3 minutes of gyro operation a ___________ to the torquer for fast erection at the start up of the gyro
higher voltage
(higher voltage at gyro start up to get spinning)
A rate gyro has _____ gimbal (____ axis of freedom)
This is tied to ______ and ______
A rate gyro has 1 gimbal (1axis of freedom)
This is tied to yawing and precession
An attitude gyro has _____ gimbals ( ____ axis of freedom)
this is tied to ____ and _____
based on rigidity in space
An attitude gyro has 2 gimbals ( 2 axis of freedom)
this is tied to pitch and roll
based on rigidity in spa
Instead of an electric motor, you can have gyro using a ______ or ________
venturi or an EDP (engine driven pump)
Explain inclination
Inclination is the weighted end of the compass pointer at the equator end (not the pointer end) as it tends to point inwards
Explain Variation
Variation is the difference between True North and Magnetic North (Isogonic lines)
Explain Deviation
Deviation is the difference between Magnetic North and Compensated North as it needs to compensate for the error in the compass caused by the electrical systems (EMI)
