Flight Instruments, Displays

Question 1

What directly provides inertial position and track data to the associated FMC?

Answer 1

The 2 ADIRUs (Air Data Inertial Reference Units)

Also produces flight data: position, speed, altitude, attitude, for flight displays, FMCs, flight controls, engine controls, and other systems.

*Auxiliary Pitot Probe and 2 Alternate static ports used by Stby system. Not used by ADIRS

Question 2

If both the Captain and FO pitot tubes are inoperative (damaged/blocked), how is airspeed provided?

Answer 2

Auxiliary pitot probe and 2 alternate static ports provide airspeed to Standby Instruments.

Question 3

What are the standby instruments?

Answer 3

Standby:
-magnetic compass
-attitude indicator
-Altimeter/airspeed indicator
-radio magnetic indicator (RMI if installed)
—directional gyro with 2 VOR/ADF needles
—narrow needle: VHF or ADF no 1
—wide needle: VHF no 2

Or

-Integrated Standby Flight Display (ISFD)
-RMI if installed

Question 4

How is the Integrated Standby Flight Display battery pack and charger powered?

Answer 4

The Battery Bus

When Battery Bus unavailable, battery back provides ISFD with 150 min of power.

*when Battery Switch placed OFF, all power removed from ISFD and powers down

Question 5

If the outboard display fails, is automatic switching available? If so, where is the PFD displayed?

Answer 5

Yes, inboard DU

-inboard DU fails, it blanks, PFD remains on outboard DU

-upper display (center) fails, primary engine display moves to lower display, upper blanks. If secondary is on lower, a compact engine display is displayed

-no auto switching for lower DU

Question 6

What indicates maximum operating speed?

Answer 6

Vmax indicated by vertical bar of red and black alternating hash marks. Bottom of bar (top of airspeed tape) indicates Vmax.

Least of:
-Vmo MMO
-gear placard speed
-flap placard speed

Question 7

How are maneuver speeds indicated?

Answer 7

Vmvr
-top of the (lower) Amber band indicates minimum speed for full maneuver capability
—1.3g capability to stick shaker/initial buffet
—1.3g to low speed buffet above 20,000 ft

-bottom of the (upper) Amber band indicates maximum maneuver speed and provides safe margins for maneuvering in turbulence, or with flaps extended, and for high speed buffet margins
—flaps up, max maneuver speed. 1.3g to high speed buffet
—flaps not up, indicates placard speed (Vf) for NEXT flap setting

*1.3g occurs at 40 degrees bank level flight

Question 8

With dual FMC failures, how are airspeeds set for takeoff and landing?

Answer 8

Engine Display Control Panel

Takeoff
-Auto: FMC sets speeds
-V1: manually set decision speed
-VR: manually set rotation speed
-WT: manually enter gross weight
-SET: selected after speeds set, disables disables inner knob. MAN SPD white shown right of airspeed tape
*show INVALID ENTRY in flight (above)

-Bug 5 (triangle): manually set Bug 5 (white)

Landing
-VREF: manually set reference landing speed
*show INVALID ENTRY on ground

Question 9

How is the flight path angle and drift angle displayed on the PFD?

Answer 9

The Flight Path Vector
-when selected ON via the EFIS control panel

Question 10

What are the pitch limit indicators, and when do they populate?

Answer 10

Indicates the pitch limit (stick shaker for existing flight conditions) calculated by SMYD.

Represents safe maneuver (pitch) margin for max perf climbs and wind shear escape

Displayed when:
-flaps extended, or
-airspeed approaches stick shaker for existing flight conditions regardless of flap position (Amber speed band)

Question 11

What does pushing STD on the EFIS control panel do?

Answer 11

Selects standard barometric setting (29.92 in hg or 1013 hpa. Displayed as STD green

Or

Toggles from std to preselected altimeter setting (small white numbers below STD) or 29.92 of nothing preselected

Question 12

What is the difference in the CDS alerts on the PFD and when would you use them?

Answer 12

CDS MAINT (white)
-a dispatchable CDS fault has occurred
-displayed ground only, prior to start of the 2nd engine

CDS FAULT (Amber)
-a non-dispatchable CDS fault has occurred
-displayed ground only prior to start of 2nd engine

Question 13

What causes the airspeed (IAS DISAGREE) alert?

Answer 13

Amber on both lower airspeed tapes

Captain and FO airspeed indications disagree by more than 5 kts for 5 continuous seconds

Question 14

What causes the altitude (ALT DISAGREE) alert?

Answer 14

Amber on both Lowe altitude tapes

Captain and FO altitude disagree by more than 200 ft for more than 5 continuous seconds

Question 15

What causes the angle of attack (AOA DISAGREE) alert?

Answer 15

Amber below both airspeed tapes

Left and right AOA values disagree by more than 10 degrees for more than 10 continuous seconds

*alert active above 400 ft RA, also remains until landing when descending through 400 ft RA

Question 16

Using the Vertical Situation Display (VSD), how would you know if you will achieve target speed within a certain distance?

Answer 16

Range to Target Speed Dot (RTSD)
-indicates where aircraft will achieve FMC/MCL target speed
-is blanked within 5kts
-reappears if speed increases 10 kts or more above target
-replaced with infilled dot at vector end of target speed cannot be achieved within length of vertical flight path line

Question 17

On the VSD, altitude gates are provided at what altitude on an approach path?

Answer 17

Decision Gates are displayed on the FMC approach glide path or 3 degree reference line at
-1000 ft (white) Gate
—“should” be in final landing configuration
—may be continued if will be by 500 gate
-500 ft (Amber) Gate
—“should” meet all stable approach criteria
—may be continued if will be by 300 ft (not displayed) stable approach limit.

Question 18

In addition to the PFD, which displays use failure flags to indicate systems failures?

Answer 18

ND (navigation display)

Standby instruments