MAX - Flight Instruments, Displays

What is the purpose of the Display Processing Computers (DPCs)?

MAX Display System (MDS):

• Two identical DPCs

• DPC interfaces with aircraft subsystems and sensors to collect data

• Collected data is then processed and displayed on Flight Deck DUs

How are outboard Display Unit failures automatically handled?

Displays automatically reconfigure to ensure:

• Each pilot has a PFD

• An Engine Display is shown

How are the standby instruments provided airspeed and altitude information?

Air data from direct connections to auxiliary pitot and alternate static

How is inertial position and track data provided to the FMC?

ADIRUs provide:

• Inertial position and track data to FMC

AND

• Attitude, altitude, and airspeed data to displays

How is maximum operating speed indicated on the PFD?

RED AND BLACK BAR

Bottom of bar indicates maximum speed as limited by lowest of the following:

• VMO/MMO

• Landing gear placard speed

• Flap placard speed

What does the VNAV speed band on the PFD indicate?

• FMC target airspeed during VNAV PTH descents

• Bottom of bar indicates autothrottle wake-up speed

• Top of bar indicates speed VNAV will change VNAV PTH to VNAV SPD.

When do the Amber Pitch Limit Indicators (PLIs) display?

Indicates pitch limit (stick shaker activation for existing flight conditions)

• displayed when the flaps are not up

• displayed at slow speeds with the flaps up

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

Flight Path Vector (FPV) Indication (white) when selected on the EFIS control panel:

• Flight path angle is displayed relative to horizon line

• Drift angle is displayed relative to display center

How is standard pressure set on the altimeter?

Barometric Standard (STD) switch, EFIS control panel.

What does the ALT DISAGREE alert indicate?

• Captain's and First Officer's altitude values disagree by >200 ft for >5 seconds

• Alert is shown on both PFDs

• Does not indicate which altitude value is erroneous

What does the IAS DISAGREE alert indicate?

• Captain's and First Officer's airspeed values disagree by >5 kts for >5 seconds

• Alert is shown on both PFDs

• Does not indicate which airspeed value is erroneous.

What does the AOA DISAGREE alert indicate?

• Captain's and First Officer's AOA values disagree by >10° for >10 seconds

• Alert is shown on both PFDs

• Does not indicate which AOA value is erroneous

• What does the solid green dot along the vertical flight path vector of the Vertical Situation Display (VSD) indicate?

• Where aircraft will achieve FMC or MCP target speed

• If aircraft is within 5 kts of target speed, dot will be blanked

• If aircraft increases 10 kts or more faster than target speed dot will reappear

• Unfilled dot at end of Flight Path Vector if target speed not achieved w/in vector length

At what altitudes are decision gates on the VSD provided?

• Indicates suggested points where aircraft should be path and speed stable on APP

• Gates are placed on 3-Degree Ref Line or FMC APPGlide Path Angle Line:

  • 1000 ft above field elevation (White)

  • 500 ft above field elevation (Amber)

• Decision gates below missed approach waypoint altitude will not be displayed

How is the HGS system controlled?

HGS is controlled from a menu within the MCDU

What components comprise the HGS?

• HGS Computer

• Overhead Unit

• Combiner

  • Optically combines symbology from Overhead Unit with pilot's view through windscreen

• Annunciator panel on First Officer's AUX panel, normally on outboard display

What standby instrument(s) are available?

• Standby magnetic compass

• Integrated Standby Flight Display (ISFD)

How is the Integrated Standby Flight Display (ISFD) powered?

Battery Bus

Which displays utilize failure flags to display instrument failures?

Primary Flight Display (PFD)