Automatic Flight System Flashcards
On the ground, how do you arm the flight director TOGA mode?
Turn the FD on. Either switch will arm the mode
In flight, with the autopilot and flight directors off, you flip a FD switch on. What does the FD do for vertical and lateral modes? (AKA what are the default FD modes)
Pitch mode: V/S
Roll mode:
Bank less than 5 degrees: HDG HOLD
Bank greater than 5 degrees: Attitude hold (ATT)
Can you have the autopilot engages but flight directors off?
Yes
You are hand flying the approach and see the runway, kill the FD. Then you go around. Do you have to reactivate the FD?
No. This is the one example where the FD will display even with the FD switches selected to OFF. When you press the TOGA switch with airspeed greater than 80 and flaps greater than UP, the FD shows up automatically.
What are the default autopilot modes? (When FD off and you engage the AP)
Same exact as default FD modes:
Pitch mode: V/S
Roll mode:
Bank less than 5 degrees: HDG HOLD
Bank greater than 5 degrees: Attitude hold (ATT)
What are the 2 basic autothrottle modes?
Thrust or speed
Thrust mode: Maintains speed using thrust
Speed mode: fixed thrust setting, maintains speed using elevator
What does the A/T switch do?
It arms the autothrottle. When you select a FD mode it will automatically engage for the appropriate mode.
Thrust mode: Speed switch pushed + ALT mode, V/S, or G/S
Speed mode: VNAV, FLCH, or TOGA witches pushed
ALSO: When A/T is armed but no mode throttle selected, cycling thew A/T switch off and back to armed when in VNAV or FLCH SPD
What is the thrust (THR) switch for?
-It is a dual purpose switch. The 2 purposes are 1.) selecting reference (reduced) thrust setting after takeoff or go around. (will not be illuminated) 2.) To tell the autothrottle what mode you want it in (THR REF-will be illuminated)
-Available 400’ after takeoff, when pushed it reduces thrust to CLB thrust (CON if 1 engine inoperative)
What is the speed (SPD) switch for?
Operative from 400’ after takeoff, when pushed it illuminates and selects the A/T speed mode to maintain a specific speed using thrust changes.
When power is first applied, what speed sets in the IAS/MACH window?
200 knots
Does the IAS/MACH window automatically change from IAS to MACH or the other way around?
Yes.
In climb: Changes from IAS-MACH at about .84
In descent: Changes from MACH-IAS around 310 knots
If the IAS/MACH window is blank, what does this mean?
That the FMC is controlling the speed
What does the IAS/MACH (SEL) switch do?
It changes between IAS and MACH (must be greater than .4 MACH to switch from IAS-MACH)
What does the knob directly under the IAS/MACH window do?
it allows you to set desired speed. You can push it when in FMC speed (blank) and it will display a speed that you can select (speed intervention).
The LNAV switch is pretty simple, it arms or activates LNAV. What are the only 2 important caveats to remember about LNAV?
1.) You can’t arm LNAV until at least 50’ AGL above the runway
2.) LNAV can be armed outside 2.5 miles, but it won’t engage until within 2.5 miles of the course
What are the VNAV modes?
VNAV SPD, VNAV PTH, VNAV ALT
When armed, VNAV activates________ after takeoff.
at 400 AGL
What does the FLCH switch do?
Selects the FLCH SPD mode
-Opens the IAS/MACH window
-Pitch commands based on speed
What does the HDG bank limit dial do?
AUTO: AFDS commands bank within range of 15-25 degrees based on various conditions
5,10, 15, 20, 25: Specific manual bank limits
SEL: Pushing in selects HDG SEL mode (flys that heading) Basically heading mode
What does the HOLD button do under the HDG section?
Selects HDG HOLD mode (holds the heading you are currently on the moment you press the button
What does the V/S switch do?
Selects the pitch mode to vertical speed, can manipulate the rate using the dial and window
What does the dial beneath the ALT window do?
Spin: That is how you spin to select the altitude in the altitude window
Push: 1.) Deletes any FMC altitude constraints (climb/descend direct)
2.) With no FMC altitude constraints, pushing it changes the cruise altitude to what is in the window
3.) During cruise when you select a higher or lower altitude and you are in VNAV ALT or VNAV PTH, it climbs or descends to the new altitude
4.) Within 50NM of TOD, pushing it activates DES NOW
What does the HOLD switch do in the ALT section of the MCP?
Selects ALT mode (holds the current altitude you were at when you pressed the button)
What does the LOC switch do?
Arms LOC roll mode
You must be within ____ degrees to capture a localizer
120
What does the APP switch do?
Arms both the LOC and G/S modes
APP mode can’t capture the glideslope until within _____ degrees of localizer course
80
You must be below ____ knots on takeoff for the A/T to engage when you press the TOGA switch
50 knots
How many flight control computers does the AFDS have?
3
What control surfaces does the autopilot control?
Ailerons and elevators. (Multi autopilots control the rudders during an approach)
On landing rollout, when does the autothrottle disengage?
Selection of reverse thrust
What is the VNAV climb speed after takeoff and once flaps are up?
It selects either VREF+100 or the FMC speed transition
When TOGA is pressed and the autothrottle goes into THR mode, what is the minimum FPM rate of climb?
2,000 FPM
In a descent, the autothrottle may move to IDLE mode, what follows IDLE mode?
HOLD
What is ATT mode?
It is a roll mode. 3 different scenarios:
1.) Bank is between 5-30 degrees- AFDS holds your current bank
2.) Bank is over 30 degrees- AFDS holds 30 degrees
3.) Bank is less than 5 degrees- AFDS goes into HDG HOLD
What does the TOGA roll mode do?
Maintains ground track
What does the ROLLOUT roll mode do?
Keeps the plane on the localizer during landing rollout. Displays below 1,500’ and activates below 5’
What does the TOGA pitch mode do?
TAKEOFF:
1.) On ground- sets FD for 8 degrees
2.) After takeoff, commands pitch to V2+10. If speed remains above this range for 5 seconds, it pitches for current speed to a maximum of V2+25
GO AROUND:
1.) Commands target speed. If exceeded for more than 5 seconds target speed is reset to current speed to a maximum of IAS/MACH window plus 25 knots
What does the FLARE pitch mode do?
It enables the aircraft to flare. Displays below 1,500’ and activates between 60-40 RA. Deactivates at touchdown
On a go-around, what does the first press of the TOGA switch do?
THR establish minimum climb rate of 2,000 FPM
On a go-around, what does a second press of the TOGA switch do?
THR RED at full go around thrust
What pitch does the FD command during a windshear escape after TOGA is pressed?
15 degrees, respecting the PLI
Later transitions from pitch to speed control once within a rate of climb of 600-1200FPM
What flight envelope protections does the AFDS have?
Stall protection: Prevents speed below minimum maneuvering speed
Overspeed protection: FMC uses a 5 knot margin. (No overspeed protection in V/S or engine failure above max EO ALT
