Avionics Flashcards
Describe the Modular Avionics Units (MAU’s).
They’re the main computers and processors that control most of the avionics related applications on the aircraft.
Describe the function of the Touch Control Steering (TCS) button.
When pressed and held, it momentarily interrupts the autopilot.
Which display units (DU’s) are referred to as Multifunction Displays (MFD’s)?
DU #2 and #3
Which DU can be failed for dispatch?
DU #3
What limitation is placed on use of the switches located on the DISPLAY SYSTEM CONTROL panel?
They’re for ground use only (i.e. for MEL dispatch ability)
What’s the primary purpose of the SMC?
To display the Standby Flight Display (SFD)
Name some occasions when the SFD is automatically displayed.
For loss of: P FD, U nusual attitudes, B reak power transfer, I nstrument comparison issues, S FD failures (either)
Can you dispatch with failure of a cursor control device (CCD)?
Yes, you can dispatch with failure of one or both CCD’s.
What part of the displays is the cursor restricted from entering?
ADIs; otherwise, it can move anywhere in a display window on its associated DU’s. It’s further restricted with SVS.
What happens if both cursors are selected to the same DU?
The last cursor wins and the first cursor is removed from the display.
What’s the purpose of the guidance panel (GP)?
It provides most of the controls for operation of the Automatic Flight Control System (AFCS).
An ATC cleared altitude should always be set into the GP preselect window by whom?
Pilot monitoring
Name some functions of the MCDU.
Calculates lateral and vertical navigation guidance for display and coupling to the Flight Guidance System, develops composite position using multiple sensor inputs, calculates all performance information, and provides radio and SSPC interface. Remember four (4) major functions: navigation, performance, radio and SSPC interface.
What does RAAS stand for?
Runway Awareness and Advisory System; runway advisories can be inhibited by depressing RAAS INHIBIT switch
What’s the source of information to the DU’s?
Three (3) MAU’s, three (3) MCDU’s and other sensors
How can a default value be restored on the MCDU during the performance initialization?
Generally by using the DELETE function on the appropriate line
How are pilot entries generally displayed on the MCDU?
Large characters
How are configuration mismatches indicated on the MCDU?
In inverse video (i.e. highlighted)
Name some functions controlled and monitored from the UTIL menu of the SMC.
Tire pressure display, the semi-mode CPCS controller, a refuel controller which also continuously displays fuel quantity, engine oil display, and hydraulic fluid quantity display
The line select adjacent to the CAS/MACH display on the PFD ADI menu toggles the airspeed tape between calibrated airspeed and mach number only when the aircraft is above what altitude?
25,000 feet. When LSK is pressed, the CAS/MACH display does not box. The only annunciation is the change of display units in the airspeed tape.
What’s the primary symbol used to control the aircraft with the HUD?
Flight Path Vector (FPV): displayed as a green circle with one green line on top and one on each side of the circle. It represents where the mass of the airplane is going. Note: caged FPV is open on the bottom.
What is a lateral discontinuity?
A lateral gap in the flight plan
How do you know if a chart is geo-referenced?
A white or green aircraft icon appears in the right corner of the chart’s title bar which enables the aircraft’s actual position (displayed as a green airplane symbol) to be displayed
While checking the SENSOR page of the SMC, what selection would you expect to see for FGC and AT?
During power up, the FGC and AT alternates between 1 and 2 every flight.
What does an amber MAG2 indicate on both PFD’s?
It alerts the crew that both pilots are using the same source for heading information: in this case, IRS #2.
What does an amber RA2 indicate on both PFD’s?
It alerts the crew that both pilots’ flight instruments are receiving radio altimeter data from the same source (i.e. on sensor page of SMC)
What’s it mean when ALT is boxed in cyan on the ENG ALT CTRL page of the SMC?
It indicates the engine is operating in the alternate control mode (i.e. engine computer controlling the speed of LP)
When are V speeds displayed with an asterisk on the FLT REF page of the SMC?
Once the FMS receives the necessary data for computation. When all FMS parameters for takeoff are met, the speeds displayed on the SMC automatically box, the asterisks are removed and the speeds are displayed on both PFD airspeed tapes.
How does the FMS compute VREF speed?
It’s based solely on flap handle position, current aircraft weight and altitude
What does it mean to preview a course?
The PREVIEW prompt on the SMC enables the crew to select a short range NAV source for display on the HSI even though FMS (long range navigation) is still the active nav source.
What do the top “T” and bottom inverted “T” represent on the combiner during the HUD test?
Upper and lower limit of data displayed on the HUD
What’s the normal display location of primary engine instruments and CAS?
When the 2/3 window format is selected for DU2 and DU3, primary engine instrument information is always displayed in the upper 1/6 window on DU2. CAS information is normally displayed in the upper 1/6 window on DU3.
What’s the restriction on selection of full windows on DU2 and DU3?
The full window cannot be selected on both DU2 and DU3 at the same time.
What’s the source of HUD symbols?
HUD computer
What’s the source of the EVS image?
The EVS camera, unlike the HUD, uses infrared technology and is optimized to detect runway lighting.
How should the cloth cover be removed from the combiner?
Rockwell Collins recommends removing the cloth cover after the combiner is moved to the operating position. In like fashion, they recommend reattaching the cloth cover before moving the combiner to the stow position.
How would you know that you haven’t placed the combiner in the correct operating position?
An “ALIGN HUD” message appears on the combiner display. If this occurs, carefully reposition the combiner glass and allow it to snap into the detents. Don’t use the HUD if the “ALIGN HUD” message continues to be displayed.
Why does the combiner have a breakaway position?
It’s a safety feature that allows the combiner glass to rotate toward the windscreen with head impact and lock in place during a sudden deceleration of the aircraft. This minimizes head injury.
What is NUC?
NUC stands for Non-Uniformity Correction. It’s a calibration process that results in a cleaner picture and occurs during camera power-up, flaps selected from 0° to 10°, or manual NUC selected.
How do you know when the EVS image is available for display?
After camera cool down, the system performs a NUC check, then FLIR flashes on the combiner and goes steady or EVS A, H, or L is displayed. If aircraft is cold or hot soaked, cool down may take up to 35 minutes.
HUD symbols are described as being either conformal or non-conformal. What’s the difference?
A conformal symbol has a real-world counterpart (e.g. the horizon line represents the horizon degree for degree).The altitude dial is considered non-conformal since it doesn’t represent anything in the real world.
What does the Aircraft Reference symbol (or Boresight symbol) represent on the HUD?
The projected centerline of the aircraft (boresight)
Why does the horizon line flash on the HUD at nose high and nose low attitudes?
To indicate that it’s no longer conformal
What’s the difference between the uncaged and caged modes on the HUD?
In the UNCAGED mode, the FPV is free to roam horizontally and vertically. In the CAGED mode, the FPV is free to move vertically; however, it’s locked in the horizontal center. This is necessary to keep the FPV from drifting off the lateral
limits of the combiner in high cross winds. In the CAGED mode, the FPV indicates the plane’s heading and the ghost FPV represents your track. In the UNCAGED mode, the boresight represents your heading and the FPV represents your track.
Describe the three (3) different levels of EVS camera gain.
AUTO, H for high, and L for low. Select AUTO if you want the camera to automatically adjust the gain, H for low visibility, and L for night VMC or day with smog. Indications of your selection appear on the upper left portion of the combiner: EVS A for AUTO, EVS H for high, or EVS L for low.
Describe operation of the EVS WSHLD HT switch.
When selected, the switchlight indicates blue ON and two minutes of continuous heating is provided to the EVS windshield. Otherwise, operation is automatic if the aircraft is airborne and cowl anti-ice is ON.
How is heat depicted on the EVS image?
Hotter items from the IR camera are depicted on the FLIR synoptic video page 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 your chances of seeing approach and runway lights with EVS in low visibility?
Make sure the lights are set to full bright prior to commencing the approach and select high gain
What are the requirements for descending below DA with EVS?
You need EVS lights to descend below DA and you need visual cues without the aid of EVS at 100 ft above TDZE in order to continue and land.
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 an obstacle-free path is present?
An obstacle-free path is present if runway is served by an approach to a Decision Altitude (DA).
At what altitude does the airport symbol normally appear on the HUD?
2000’ above airport
When does the runway symbol replace the airport symbol?
At 350 ft RA, the runway symbol joins the airport symbol and at 325 ft RA, the airport symbol disappears. The runway symbol is removed from the display at 60ft RA.
When does the flare cue appear?
Flare cues appear at 100 ft and move upward as the aircraft approaches the ground and provides flare guidance.
What is provided on the HUD unusual attitude display to prevent you from over stressing the aircraft during the recovery?
G-load digital readout
What is RNP?
Required nav performance is the 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 is the calculated estimate of accuracy of navigation equipment aboard the aircraft. If EPU exceeds RNP, the numbers are highlighted by a cautionary amber overlay and the CDI needle turns amber.
