Avionics Flashcards
- Describe Modular Avionics Units (MAUs).
They’re the main computers and processors that control most avionics related applications on aircraft.
- Which display units (DUs) are referred to as Multifunction Displays (MFDs)?
DU #2 and #3
- What part display is cursor restricted from entering?
ADI and PEI; otherwise, it can move anywhere in a display window on its associated DUs.
- What happens if both cursors are selected to the same DU?
Last active cursor has exclusive control in making selections within the display in which both cursors reside.
- What’s the purpose of Guidance Panel?
It provides most of controls for operation of Automatic Flight Control System (AFCS).
- What does an amber MAG2 indicate on both PFDs?
It alerts the crew that both pilots are using same source for heading information: in this case, IRS #2.
- What does an amber RA2 indicate on both PFDs?
It alerts the crew that both pilots’ flight instruments are receiving radio altimeter data from same source.
- What’s the purpose of 121.5 EMER guarded physical switch located on side wall above oxygen mask?
Enables selection of emergency frequency for total TSC failure.
- What happens with selection of Call Inhibit?
Prevents GCMS related messages from displaying on CAS display.
- What’s the normal location of primary engine instruments?
DU2 upper.
- What’s the normal location of CAS display?
DU3 upper.
- What’s the restriction on selection of full windows on DU2 and DU3?
Cannot be selected on both DU2 and DU3 at the same time.
- What functions are available with Phase-Of-Flight (POF) presets?
They can be selected, stored, and reset.
- What’s the source of HUD symbols?
HUD computer.
- What’s the source of video image?
EVS image comes from a camera that uses infrared technology and is optimized to detect runway lighting; Synthetic Vision synthesizes flight information from multiple onboard databases, GPS and inertial reference systems into a complete, easy-to-understand 3-D rendering of forward terrain.
- How should cloth cover be removed from combiner?
Rockwell Collins recommends removing cloth cover after moving combiner to operating position. In like fashion, they recommend reattaching cloth cover before moving combiner to stow position.
- How would you know you haven’t placed combiner in correct operating position?
“ALIGN HUD” message appears on combiner display. If this occurs, carefully reposition combiner glass and allow it to snap into detents. Don’t use HUD if “ALIGN HUD” message continues to be displayed.
- Why does combiner have a breakaway position?
It’s a safety feature that allows combiner glass to rotate toward windscreen with head impact and lock in place during sudden aircraft deceleration. This minimizes head injury.
- What do top “T” and bottom inverted “T” represent on combiner during HUD Press and Hold test?
Upper and lower limit of data displayed on HUD.
- What’s the primary symbol used to control aircraft with the HUD?
Flight Path Vector (FPV)
- What does Aircraft Reference symbol (or Boresight symbol) represent on HUD?
Projected centerline of aircraft (boresight).
- What’s the difference between HUD uncaged and caged modes?
In UNCAGED mode, FPV is free to roam horizontally and vertically. In CAGED mode, FPV is free to move vertically; however, it’s locked in horizontal center. In CAGED mode, FPV indicates plane’s heading and ghost FPV represents track. In UNCAGED mode, boresight represents heading and FPV represents track.
- HUD symbols are described as being either conformal or non-conformal. What’s the difference?
Conformal symbol has real-world counterpart (e.g., the horizon line represents the horizon degree for degree). Altitude dial is considered non-conformal since it doesn’t represent anything in real world.
- Why does horizon line flash on HUD at nose high and nose low attitudes?
To indicate non-conformity.
- How do you know EVS image is displayed?
Upper left portion of combiner indicates EVS A, H, or L. EVS power up / cool down normally takes 10-15 minutes but can take longer if aircraft is hot soaked.
- What is NUC?
NUC stands for Non-Uniformity Correction. It’s a calibration process that results in cleaner picture and occurs during camera power-up, flaps selected from 0° to 10°, or manual NUC selected.
- Describe the three (3) different levels of EVS camera gain.
AUTO, H for high, and L for low. Select AUTO if you want camera to automatically adjust gain, H for low visibility, and L for night VMC or day with smog. Indications of your selection appear on upper left portion of combiner: EVS A for AUTO, EVS H for high, or EVS L for low.
- How is heat depicted on EVS image?
Hotter items from IR camera are depicted as lighter while items with less heat are depicted as darker.
- Describe some factors that affect EVS performance.
Thick clouds, thermal crossover, blooming, and misalignment.
- How can you increase chances of seeing approach and runway lights with EVS in low visibility?
Make sure lights are set to full bright prior to commencing the approach and select high gain.
- What are requirements for descending below DA with EVS?
You need EFVS lights to descend below DA and you need visual cues without the aid of EFVS at 100 ft above TDZE in order to continue and land unless qualified under FAR 91.176 (a) to continue and land with EFVS in lieu of natural vision.
- Flight director or autopilot with vertical guidance, either ILS or FMS vertical path, is required for all IMC EVS approaches. How do you determine if obstacle-free path is present?
Runway is served by an approach to Decision Altitude (DA).
- At what altitude does airport symbol normally appear on HUD?
2000’ above airport.
- When does runway symbol replace the airport symbol?
At 350 ft RA, runway symbol joins airport symbol and at 325 ft RA, airport symbol disappears. Runway symbol is removed from display at 60 ft RA.
- When does flare cue appear?
100 ft; it moves upward as aircraft approaches the ground and provides flare guidance.
- What is provided on HUD unusual attitude display to prevent you from over stressing the aircraft during recovery?
G-load digital readout.
- What is RNP?
Required nav performance: accuracy in NM required for navigation in the area the aircraft is flying and affects CDI sensitivity (i.e., lower RNP equates to greater CDI sensitivity).
- What is EPU?
Estimated position uncertainty: calculated estimate of accuracy of navigation equipment aboard aircraft. If EPU > RNP, numbers are highlighted by cautionary amber overlay and CDI needle turns amber.
- What does magenta dashed line extending from nose of aircraft to compass arc represent on map display?
IRS track vector
- How do you know if a chart is geo-referenced?
A white or green icon appears in right corner of chart’s title bar which enables aircraft’s actual position (displayed as green airplane symbol) to be displayed.
- What color messages can be scrolled off the CAS display?
Amber, blue and white: red can only be scrolled out of view to show other red messages.
- What happens when a red or amber CAS message becomes active?
Message displays in inverse video, aural alert sounds (i.e., three chimes for red or two for amber), and respective annunciator on master warning panel illuminates (i.e., red WARN for red or amber CAUT for amber). When annunciator/button is pushed on master warning panel, annunciator extinguishes, tone silences, and message displays normally. If there are red messages already on CAS display when new red message becomes active, new message displays at top of red message stack. If there are amber messages already on CAS display when new amber message becomes active, new message displays at top of amber message stack.