Flight Management & Navigation Flashcards
What information do the IRSs provide? Are they dependent on, or independent of external navigation aids?
Position, ground speed, and attitude data.
Independent of external navigation.
When does IRS position and ground speed information become available?
Once the IRS is aligned on the ground.
How long does IRS alignment take?
5-17 minutes
When does the ALIGN (white) illuminate steady on the IRS panel?
When the respective IRS is operating in either the:
-ALIGN mode
-initial ATT mode, or
-shutdown cycle
What does a flashing ALIGN (white) on the IRS panel during preflight indicate?
Alignment cannot be completed due to IRS detection of:
-significant difference between previous and entered positions or unreasonable position or
-no present position entry
What could cause the call horn in the nose wheel well to sound while the aircraft is on the ground?
The IRS is operating on DC power from the switched hot battery bus
Without AC power, how long can the IRSs operate? What light(s) will you see?
Power to the right side IRS is automatically terminated if AC power is not restored within 5 minutes.
“ON DC” caution light illuminates
If a system fault affecting the related IRS ATT and/or NAV modes has been detected, what indication will you get?
FAULT (amber) light illuminates.
What does an VERIFY POSITION scratchpad message indicate?
The lat/lon position is not within 4nm of the origin airport.
How many GPS receivers are installed?
2
How is the GPS activated and what does it provide data for?
Auto activation
Independent geographical position is sent to the FMC and time data is sent to the clocks.
With the FMC SOURCE select switch in NORMAL, which FMC is primary?
Left side FMC
What’s the criteria for airports to be included in the nav database?
At least 1 paved runway that is at least:
-5000’ long
-100’ wide
-has an instrument approach procedure.
When using the Autothrottle system, which system calculates reference thrust limits, and how is that thrust equalization maintained?
Thrust limits are calculated through the FMC
Commands thrust equalization through the Electronic Engine Control (EEC)
Are the FMCs independent of one another? Do they compare information?
-Yes they are independent
-Yes, the second FMC serves as a backup, providing complete navigational functions if the other FMC fails.
Where do the FMCs receive their inertial data from?
Their on-side ADIRU
How can takeoff thrust be derated?
Can be selected in the FMC on the N1 LIMIT page.
What sources do the FMCs use to determine position? IN what order?
-GPS
-2 or more DME stations
-one VOR with a co-located DME
-one localizer and co-located DME
-one localizer
What criteria must be met for LNAV engagement?
-When laterally 3nm of the active route leg.
-If outside of 3nm of the active route leg, LNAV engages if on an intercept heading of 90 degrees or less and the intercept will occur before the active waypoint.
How does the FMC calculate a descent path during a VNAV PTH descent?
Computed prior to top of descent and then is frozen unless the pilot executes a major edit to the flight plan.
Looks at the end of descent (E/D) point and works backwards up to cruise altitude. Factoring in airspeed and altitude restrictions.
The DC Fail (amber) light, when illuminated, indicates?
DC power for the related IRS is not normal
What are indications of a left FMC failure?
FMC alert light illuminates. The MENU page appears on both CDUs. VTK appears on the left navigation display. LNAV and VNAV will disengage, but can be reengaged if Autopilot B is in use or is selected
LNAV will engage when?
Laterally positioned within 3nm of the active route leg.
In the MAX, the FMC Alert light includes which new indication?
Runway Disagree
In the MAX, what fuel indications are on the Fuel Progress Page 5/5?
APU Fuel Used
Totalizer
Calculated
