Automatic Flight Flashcards
Which modes do F/Ds activate in with Autopilot off?
Ground:
- First F/D positioned ON arms:
- roll mode: Takeoff/Go-Around (TO/GA)
- pitch mode: TO/GA
Flight:
- First F/D positioned ON activates
- roll mode: HDG HOLD or ATT (if bank angel greater than 5º when activated)
- pitch mode: V/S
When is Autothrottle (A/T) activated?
A/T Arm switch in ARM position and:
- VNAV, FLCH, or TO/GA pushed
- SPD switch pushed while pitch mode is ALT, V/S, or G/S
When does IAS/MACH window change from IAS to MACH?
- In Climb IAS to MACH at approx .84 Mach
- In Decent MACH to IAS at approx 310 knts
*can the select (SEL) switch to toggle between IAS and MACH
What determines Bank Limiter in AUTO?
- bank varies between 15 - 25 degrees depending on TAS, flap position, and V2
With in how many degrees can localizer be captured in LOC?
Intercept track angle within 120 degrees of localizer course
How can LOC mode me deactivated after localizer capture?
- selecting a roll mode other than LNAV
- pushing TO/GO switch
- disengage AP and turn F/Ds off
Flight Mode Annunciator (FMA) columns and colors
Columns: A/T | AFDS Roll Modes | AFDS Pitch Modes
Colors: white = armed, green = active
Autopilot Disengagement Switch
First Push:
- disengages all autopilots
- master warning illuminates
- EICAS warning message
- wailer aural warning (1 sec)
Second Push - resets:
- master warning
- EICAS warning message
- aural warning
Components of Autopilot Flight Director System (AFDS)
- 3 Flight Control Computers (FCCs) - left, center, and right
- FCCs control separate hydraulically powered A/P servos (L FCC —> L HYD servo, C FCC —> C HYD servo, R FCC —> R HYD servo)
- Mode Control Panel (MCP)
AFDS Status Annunciations
FD: FD ON and AP not engaged
CMD: AP engaged
LAND 3: 3 APs engaged and operating normally for autoland
LAND 2: AFDS redundancy reduced
NO AUTOLAND: AFDS is unable to perform Autoland
When does ROLLOUT become armed and active?
Armed - below 1,500’ RA
Active - below 5’
*after touchdown AFDS uses rudder and nosewheel steering to maintain localizer centerline
What does TO/GA command for pitch during takeoff?
On ground: Initial 8º pitch for rotation
*TO/GA pitch become active after rotation
After takeoff AFDS commands pitch to maintain:
- target speed of V2 plus 10 knts or rotation speed plus 10 knts, whichever is greater (limited to V2 plus 25) - IAS/MACH speed if speed is greater that target
If engine failure occurs:
- target speed of V2 or rotation speed (limited to V2 plus 10)
What does the AFDS command for windshear recovery?
After pressing TO/GA:
- initial pitch of 15º or slightly below pitch limit
- with increasing climb rate command transitions from pitch to airspeed control
- target airspeed is IAS/MACH or current airspeed when TO/GA activated, whichever is greater
- if AP not engaged aircraft my be flown manually following FDs
- if A/T not engaged throttles must be advanced manually
What protections are provided my automatic flight control system?
1) Stall Protection
- prevents speed reduction below minimum maneuvering speed
2) Overspeed Protection
- prevents exceeding maximum operating, gear extended, or flap placard speed
* FMC provided minimum and maximum speeds with a 5knt margin
* if FMC is unavailable speeds are provided by internal FCC speed limits
* spreed protection not available in V/S or during engine failure above min engine out altitude
Thrust (THR) switch
- switch operative at 400’
- after takeoff in VNAV or FLCH; change reference thrust limit to armed climb thrust limit; or CON if engine inoperative
- after go-around, changes reference thrust limit to CLB, or CON if engine inoperative
With light on:
- changes A/T mode to THR REF
What happens when you push IAS/MACH selector with VNAV active
- opens or closes IAS/MACH window
- closed: FMC computes target speed
- open: FMC speed-intervention is active and command speed can be selected
* if in VNAV PATH ——> VNAV SPD
When does LNAV activate?
- above 50’
- within 2.5 NM of active leg
When would LNAV deactivate?
- selecting HDG SEL or HDG HOLD
- TO/GA
- disengaging AP and selecting both FDs OFF
- loc captures
- dual FMC failure
VNAV Pitch modes
VNAV Speed: AFDS commands pitch to hold target speed
*A/T: THR REF, THR, IDLE or HOLD
VNAV PTH: AFDS company’s pitch to maintain FMC target altitude or path
*A/T: SPD
VNAV ALT: AFDS commands pitch to maintain MCP altitude
*A/T: SPD
FLCH switch
- AFDS pitches to hold selected speed
- A/T operates in THR
- A/T modulates thrust levers to give 500 fpm for each 1000’ altitude change
- AFDS attempts to reach MCP altitude within 2 mins if thrust is avail
When does G/S capture?
- loc captured
- intercept track angle within 80º of loc course
How to deselect Approach after LOC and G/S capture
- selecting TO/GA
- disengaging AP and FDs
How are mode changes emphasized on the FMA?
Green box around mode for 10 sec
Auto Throttle Active Modes
5 modes
- THR
- THR REF
- HOLD
- IDLE
- SPD
AFDS Active Roll Modes
7 modes
- HDG HOLD
- HDG SEL
- LNAV
- ATT
- LOC
- ROLLOUT
- TO/GA
AFDS ACTIVE PITCH MODES
9 modes
- TO/GA
- ALT
- V/S
- VNAV PTH
- VNAV SPD
- VNAV ALT
- G/S
- FLARE
- FLCH SPD
When is A/T operation inhibited on the ground
50 knts until 400’
Pushing TO/GA on approach
First Push:
- activates A/T in THR (GA is ref limit)
- thrust adjust to provide min 2000 fpm climb
- TO/GA roll and pitch modes
- activates F/D if no AP or F/D active
Second Push:
- activates A/T in THR REF to GA ref thrust
When do Auto Throttles disconnect
- fault in the active auto throttle mode
- reverse thrust lever to reverse idle
- dual FMC failure
- Two or more engine shutdown
- FMC selector switch (can be reactivated)
TO/GA armed in flight
- Flaps out of up
- G/S captured
Bottom of Amber bar (Max maneuvering speed)
- 1.3g maneuver capability to high speed buffet
* 1.3g maneuver capability occurs at 40º of bank in level flight
When are Derated Climb thrusts removed?
- CLB 1 uses 10% derate of CLB thrust to 10,000’
- CLB 2 uses 20% derate of CLB thrust to 10,000’
- thrust increases linearly with altitude to CLB thrust at 15,000’
Top of the Amber Bar (minimum maneuvering speed)
- 3g maneuver capability:
- to stick shaker with flaps down
- to stick shaker or Vref+80, whichever is less, with flaps up below 20,000’
- to low speed buffet, with flaps up above 20,000’
*1.3g maneuver capability occurs at 40º of bank in level flight
What does Maximum Speed indicate (bottoms of red tape)?
- Vmo/Mmo
- landing gear placard speed
- flap placard speed
What does Minimum Speed indicate (top of red tape)
- airspeed where stick shaker or low speed buffet occurs
Phases of Flight
Takeoff:
TO/GA selected ——> thrust reduction
Climb:
thrust reduction ——> top of climb
Cruise:
Top of climb ——> top of descent
Descent:
Top of descent ——> approach phase
Approach:
First waypoint of the procedure sequences or within 25 NM with runway as active waypoint
Flight Complete:
30 seconds after engine shutdown
AFDS status annunciations
5 modes
FD - FD ON and AP not engaged
CMD - autopilot engaged
LAND 3 - 3 APs engaged and operating normally
LAND 2 - 2 APs available; AFDS redundancy reduced
NO AUTOLAND - AFDS unable to make autoland
When is ROLLOUT armed and active?
Armed - 1,500’
Active - below 5’
- AFDS uses rudder and nose wheel steering to maintain loc centerline
Which ways can CON thrust be selected?
- THR after engine out
- CDU Thrust Limit page
- VNAV EO page
- automatically set with flaps up and Vref + 98
What flight controls do the autopilots command when A/P is activated?
Single A/P - ailerons and elevators
Multi A/P approach - Ailerons, elevators, and rudder
* nosewheel steering added during ROLLOUT for autoland
Describe Autopilot control during LAND 2 or LAND 3
- APs control rudder during autoland (multi A/P approaches) to compensate for crosswind and engine out
- rudder control active when LAND 2 or LAND 3 annunciated
Crosswinds requiring more that 10º crab:
- 500’: runway alignment with 5º side slip (config maintain until landing)
Crosswinds requiring between 5º and 10º crab:
- 500’: initial runway alignment
- 200’: second alignment to increase side slip and reduce crab angle
Crosswinds requiring less than 5º crab:
- 200’: runway alignment where side slip introduced
Engine Failure:
- sideslip and wings level config start at 1,300’ or when engine failure occurs
During Rollout:
- A/P uses rudder and steering to track localizer centerline
