11.5 Flashcards
In a co-ordinated turn, what happens to the bubble on a turn and bank indicator.
The bubble will stay level.
What is the benefit of glass displays.
They are interchangeable.
Is PFD inbouard or outboard.
Outboard.
What is displayed on the upper ECAM displays
Engine info
What is displayed on the lower ECAM display
System information.
What is a below / aneroid capsule
Used in analogue instruments
Expands and contracts with changes in pressure.
List 3 pressure sensing elements
Bourdon tube
Aneroid capsule
Pressure transducer
What does a pressure transducer do?
Converts pressure to an analogue electronic signal. Can. Be converted to a digital signal through an A/D converter
How do strain gauges work and what do they do.
Convert mechanical strains into electrical signals
Strain gauge type transducers convert various physical quantities into mechanical strains of. A spring element.
What instruments are static ports connected too
ASI, VSI, ALT
Which instrument is connected to both pitot and static ports.
ASI
What is it called when the measured static pressure is different from the actual static pressure.
What causes this to occur
Static source error
Shape of fuselage and speed
What does the baffle in pitot probes do?
Prevent FOD and water entering the line.
What happens if a pitot tube is blocked/
You will get incorrect readings
What is QNH
Question bill height.
Atmospheric pressure at sea level.
What is QNE
Question nil elevation.
ISA standard
Used when you go past the transition point during climb.
What is QFE
Question field elevation
Atmospheric pressure at airfield level.
When coming into land which altimeter settings may be available to you
QNH or QFE
What is the max altitude for radio altimeters to e used
2500 ft
Why are servo assisted altimeters used
To reduce lag
What do encoding altimeters do
Send a digital code to the a/c ATC transponder. The transponder replies to an interrogation from the ATC radar, it sends the altitude information.
What kind of pressure do verticale speed indicators utilise.
Differential pressure.
Use a calibrated metering unit
Has delays
Instantaneous verticle speed indicator
Incorporates an accelerometer.
What does Vso stand for
Stall speed in landing configuration with flaps and gear down.
What does what does Vsi mean
Stall speed in clean configuration with max weight.
What does Vfe mean
Max allowable speed with flaps extended.
What does Vno mean
Max airspeed for cruise flight.
What does Vne mean
Airspeed to never exceed.
What does Mmo mean
Max Mach , prevent shock wave damage.
What does Vmo mean
Max velocity, to prevent damage to the airframe.
Of ARINC 429 and ARINC 629 which is faster and bi-directional?
ARINC 629
What type of gyro does the PFD use
Vertical gyros.
What gyro does the EHSI use
Directional/horizontal gyros
Earth tied gyros
ADIRUS compensate gyros by 15 degrees per hour.
What does gyro stability depend on
Rotational speed
It’s mass
Distance between the axis and the centre of mass
How fast do a/c powered gyro spin?
Approx 22,000 rpm.
What is procession in a gyro.
Shifts 90 degrees in the direction of rotation when a force is applied
What is real wander
Where the gyro shifts of its axis
What is apparent wander
Due to the curvature of the earth, needs to be adjusted for 15 degrees per hour.
What type of gyros are laser gyros?
Rate gyros
What are rate gyros used for
Used for turn indicators.
What does CDMVT stand for
Cadbury Diary Milk Very Tasty
Compass deviation magnetic variation true.
What is hard iron
Permanently magnetised.
What is sof iron
Easily magnetised and easily demagnetised.
What is the purpose of compass fluid
Stops hunting/swinging.
What cable does a magnetic compasses lighting use
Screened twisted pair.
What are flux valves
Where are they located
Magnetic sensory device that transmits info to an a/c compass system, regarding its orientation relative to the earths magnetic fields.
Located in wing tips.
What is static source error effected by
Angle of attack
Fuselage shape
Airspeed
Flap and gear systems.
What is meant by alpha vane
An angle of attack sensor.
What is alpha max
Alpha max is the certain angle where the airflow cannot follow the upper surface of the wing, and airflow separates.
Is not a constant value.
Glass cockpit, advantages of electronic display.
All data is presented on clear, bright, colourful displays.
Precise numerical values are shown, allowing pilots to quickly interpret info.
Take up less space.
Maintenance is easy and less expensive.
What controls electronic displays
A curser control device (CCD)
MDCU , multipurpose display control unit.
Why are cathode ray tubes not used
Bulky and prone to overheating.
What aircraft are required to have standby instruments
A/c over 5700kg are required to have a standby attitude indicator and compass.
What is the purpose of auto flight
Reduces the pilots workload.
Reduce pilot fatigue
Fatigue leads to : longer response time; impaired judgement; higher likelihood of human error.
Pilots can be more alert during critical stages of flight.
Flight director system
A guidance aid overlaid on the attitude indicator.
Shows attitude required to follow a certain trajectory.
FD can be used in manual or autoflight.
FD commands the autopilot to input it necessary trajectory.
Auto throttle system
Reduces pilot workload by controlling engine power.
Flight envelope protection
Monitors operation of autoflight to prevent abnormal flight conditions.
Flight management system
FADEC - full authority digital engine control
Autopilot channels + axis
Duplex or triplex system.
Basic stabilisation system
Closed loop servo system
**
Inner and outer autopilot loops.
Inner loop
- provides the autopilots response for stabilisation
- controls flight surfaces and makes sure they have done what their told.
Outer loop
- provides commands for inner loop.
Must have a minimum of __ ways to disengage autopilot system
2
Flight level change
Achieves a new flight level of 1000ft within 120 seconds.
Auto throttle systems.
Auto throttle
- adjusts mechanical linkages to throttle, levers move
Auto thrust
- fly-by-wire, digital signals, directly to FADEC. Levers/ controls do not move.
What is the range of VHF radios
250 knots
Line of sight
What is the range of HF radio
Worldwide.
Why is SATCOM used
It mitigates the problems associated with HF.
What is the range of VHF affected by
Height of the A/C
What speed do radio waves travel at
Speed of light, 300,000,000 m/s
When/how are radio waves produced
When a high frequency a/c current is passed through a conductor (aerial)
They radiate in all directions.
Formula for wavelength
Wavelength= velocity/frequency
What type of aerial is used on aircraft
1/4 length aerial
What is the relationship between frequency and aerial length
Higher wavelength = smaller aerial.
**
What are the frequency ranges for HF and VHF
HF = 3 - 30 MHz
VHF = 30 - 300 MHz
What is amplitude modulation
Imposes an audio frequency on to a carrier frequency.
Does this by varying the amplitude.
Communication frequency ranges
108 - 136.975
8.33 spacing gives 2280 channels
25 spacing gives 760 channels.
Which VHF aerial does ACARS use
VHF 3
Info on em waves
A transverse em wave has two fields 90 degrees to each other, electric fields or magnetic fields.
Polarisation can be horizontal or vertical and depend the electric fields vectors.
When are oscillators and resonators used
Oscillators are used for transmitting.
Resonators are used when receiving.
What frequency do marker beacons use
75 MHz
Why are vertically polarised waves used instead of horizontally.
Minimise the extent the electric field of the wave contacts the earth.
How is radio interference reduced
By static dischargers and proper bonding.
Flight interphone system
Used by members of the flight crew to communicate with each other in the cockpit.
Cabin interphone system
Allows all flight deck and cabin crew to communicate with each other
Service interphone
Provides intercom between flight crew and ground staff at maintenance points.
Only works on the ground.
Isolated in flight to prevent moisture
Uses weight on wheels switches.
Ground crew call system
Flight and ground crew to attract each others attention
What does EICAM stand for and is it Boeing or airbus
Engine indicating crew alerting system
Boeing.
When does stall warning and stick shacker start
At least 5 knots above stall speed
Before you stall
