Avionic systems Flashcards
(33 cards)
What are the benefits of achieving safe two crew operations
savings in:
- salaries
- expenses
- training
- weight
Name 5 drivers for avionic systems
- improved safety
- all weather operations
- reduction in fuel consumption
- improved aircraft performance, control and handling
- reduction in maintenance costs
Data bus:
systems interfacing directly with the pilot
- displays
- communications
- data entry & control
- flight control system
Data bus:
Aircraft state sensors
- air data systems
- inertial sensors
Data bus:
Navigation
- radio navigation
- DR navigation systems
Data bus:
External world sensors
- Infrared sensors
- Radar
Data bus:
Task automation
- house keeping mgt.
- navigation systems mgt.
- autopilot & FMS
- engine control & mgt.
Name three types of displays
- head down display (HDDs)
- head up displays (HUDs): project information in pilot’s field of view
- helmet mounted displays (HMDs): they are HUDs on the helmet
How is long range communication accomplished
Provided by high frequency (HF) radios, operating the band 2-30 MHz
How is medium range communication accomplished
Civil:
Provided by very high frequency (VHF) radios, operating the band 30-100 MHz
Military:
Provided by ultra high frequency (UHF) radios, operating the band 250-400 MHz
What communication system can be found in modern aircraft
Satellite communications (SATCOM) systems, providing reliable world-wide communication
What is ‘data entry and control’ used for
- enables the crew to interact with the avionic systems
Name systems found under ‘data entry and control’
- keyboards
- touch panels
- direct voice input (DVI) control
What two areas of flight control use electronic systems
- auto stabilisation systems
- fly-by-wire control system
list air data quantities required for control systems
- altitude
- calibrated air speed
- vertical speed
- true air speed
- Mach number
- air stream incidence angle
what measurements are needed to calculated the required air data quantities
- static pressure
- total pressure
- air temperature
why is the aircraft attitude and heading important
- for executing manoeuvres
- flying in poor weather conditions
- several avionic systems relies on it: autopilot, navigations, weapons aiming
How is attitude of an aircraft measured
- using gyros and accelerometers
- usually a body mounted (strap-down) configuration
- computer analysis this data and produces figures/display
Equation for gyroscopic precession
T = dH/dt = H˙θ
H = angular momentum = IxWr I = moment if inertia about spin axis
What are Dead reckoning navigation systems
- derive present position by estimating the distance travelled from a known position
- independent of everything
- are updated from position fixes
Name three types of dead reckoning navigation systems
- inertial navigation systems
- Dopller/heading reference systems
- air data/heading reference systems
How do radio navigation systems work
- based on satellite or ground based transmitters
- computer used to derive position from signals transmitted
i. e. GPS
What navigation systems aid in bearings during flight
- VOR/DME and TACAN from ground beacon radio transmitters of main air routes
What navigation systems help with landing approach
Instrument and microwave landing systems
