Avelo Oral Exam Flashcards
Avelo Oral Exam Guide Rev 1 - 11/8/23
What happens when we position Flight Control A switch to the STBY Rudder position?
A system:
Stby pump on
Open SRSOV (standby rudder shutoff valve)
Arm stby low pressure light
Position indicating (low pressure light extinguishes)
What happens when we position Flight Control B switch to the STBY Rudder position?
B system:
Stby pump on
Open SRSOV (standby rudder shutoff valve)
Arm stby low pressure light
Position indicating (low pressure light extinguishes)
Yaw damper off
What happens when ARM is selected on the alternate flap switch?
Arm the UP/DN switch
Activates standby pump
Closes trailing edge flap bypass valve
What is the main purpose of the alternate flap system?
With loss of hydraulic system B, trailing edge flaps can be operated up/down electrically. Leading edge devices are extended using standby hydraulic pressure and may not be retracted
Alternate flap switch limitations
Cannot retract leading edge devices
Limited to 230kts
Flaps 15 landing
Lose trailing edge flap asymmetry protection
15sec wait after releasing switch before moving switch again
5min wait after a complete extend and retract cycle for cooling before attempting another extension
Guarded spoiler switches
For maintenance only
Standby LOW QUANTITY light illuminates when
The standby hydraulic reservoir quantity is below 50%. The light is always armed
Standby LOW PRESSURE light illuminates when
The standby pump is armed and exhibiting a low pressure condition
STBY RUD ON light illuminates when
A or B flight control switch is in the STBY RUD position and the SRSOV has opened
FEEL DIFF PRESS light illuminates when
High differential pressure is measured in the elevator feel computer
SPEED TRIM FAIL light illuminates
From the FCC
Single Ch failure - illuminate annunciator only upon recall
Dual Ch failure - master caution and annunciator illuminate immediately
Conditions where Speed Trim System will operate
Most frequently during takeoffs, climbs, and go-arounds
Airspeed between 100kias and M0.6
10 seconds after takeoff
5 seconds following the release of trim switches
Autopilot not engaged
Sensing of trim requirement
How will you know the speed trim is in operation?
The trim wheels will move on their own without the autopilot engaged and without pressing trim switches
What is the Mach Trim System?
It provides speed stability above M.615 by adjusting the elevators with respect to the stabilizer as speed increases. The mach trim actuator repositions the elevator feel and centering unit which adjusts the control column to the neutral position
MACH TRIM FAIL light indicates
From the FCC
Single Ch failure - illuminate annunciator only upon recall
Dual Ch failure - master caution and annunciator illuminate immediately
AUTO SLAT FAIL indicates
Failure of the auto slat system
Failure of a single SMYD (stall management/yaw damper) computer when illuminated during recall
YAW DAMPER light illuminates when
The YD is disengaged
Fuel pumps are powered by
AC power
Cross feed is powered by
DC power
Cross feed procedure
“Low glow - make the low side glow”
(Only when the checklist says to do it)
Crossfeed valve open
Low side pumps off - low pressure lights will illuminate
Max fuel imbalance
Planned 0
1000lbs random
Why does the center tank burn fuel first?
Center tank pumps operate at a higher pressure
LOW PRESSURE light for the center tanks illuminate when
A true low pressure condition exists with the pumps selected on. The lights are inhibited when the pumps are selected off
Master Caution for LOW PRESSURE light (fuel)
Both pumps in the same tank have to illuminate for the master caution to illuminate
Why is some of the overhead panel light grey and other parts dark grey in color?
The systems in light grey are affected when the fire switch is pulled
The Engine valve and Spar valve are controlled by
(Open and closes by) engine start lever and engine fire switch
What happens when you pull a fire switch?
Silence the bell
Arm squibs
Fuel/spar shutoff valve closes
Electrics - generator trips off
Hyd shutoff valve closes (engine)
Inhibits hyd low pressure light (engine)
Disables thrust reverser
Engine bleed valve closes
Max and min fuel temps
Max 49C
Min - higher of freezing point of the fuel being used +3 or -43C
FILTER BYPASS light illuminations means
There is an impending fuel filter bypass likely due to contamination. Cross feeding is not recommended due to possible contamination
VALVE OPEN light, bright, indicates
The valve is in transit or disagrees with the commanded position
APU can suction feed from
Left tank
BATT DISCHARGE light indicates
The battery is experiencing an excessive discharge rate
BATT DISCHARGE light may illuminate when
There is a heavy draw such as apu start
TR UNIT light illuminates when
One of the transformer rectifier units has failed with the following logic:
Ground - either TR 1, 2, or 3 has experienced a fault
Flight - TR 1 or a combined failure of TR 2 and 3
ELEC light indicates
On ground: A fault in the DC or Standby electrical system
In flight: inhibited
B737 Generators
2 engine, 1 apu
Output: 115V, 400 cycle, 3 phase alternating current
MAINT button (electrical panel)
Used only by mx personnel
DRIVE light illuminates when
Low oil pressure is sensed in IDG, which is caused by one of the following:
IDG failure
Engine shutdown
Auto disconnect due to high oil temp
Disconnected via switch
Can IDG disconnected in flight be reconnected?
Cannot be reconnected
STANDBY PWR OFF light indicates
AC stby bus or DC stby bus or batt bus is not powered
GND POWER AVAILABLE light tells us
Ground power is available and power quality is good
APU GEN OFF BUS light indicates
Apu up to speed, is available, not selected, and quality is good
GEN OFF BUS light indicates
The generator breaker is open until manually selected on (does not indicate quality or availability)
SOURCE OFF light indicates
The source of power has not been manually selected to power that transfer bus (or it disconnected)
TRANSFER BUS OFF light indicates
The respective AC transfer bus is not powered, it is off
Cross bus tie relay would (automatically) open when
On glideslope intercept on an ILS when either the AP or FD is in use
APU start attempts are not recommended above
FL250
APU MAINT light indicates
Apu needs mx/low on oil
APU shuts down automatically when
Low oil pressure
Fault
Over speed
Apu fire
Batt switch positioned off
How long must the apu be running before selecting the apu as a bleed source?
2 min
How long must you wait after turning off the apu before switching the battery switch off?
2 minutes
IDG disconnect can be verified by
Checking voltage and frequency from the generator on the AC meter
How does the standby power switch work in the AUTO position with a loss of ac power?
AC stby bus is powered by battery through static inverter
DC stby bus is powered by battery
Batt bus is powered by battery
How does the standby power switch work in the BATT position?
AC stby bus is powered by battery through static inverter
DC stby bus is powered by battery
Batt bus is powered by battery
DC system volts
24V battery
28V system
Equipment Cooling amber OFF light indicates
We do not have sufficient airflow for the selected fan
Emergency exit lights, armed, would come on automatically if
DC bus 1 fails or AC power is turned off
Window OVERHEAT light illuminates when
A window overheat condition exists or electrical power to window has been interrupted
Window heat ON indication
If the windows are already at the desired temperature, the window heat will not turn on, and no ON indication. A window heat power test will force power to all windows
When operating on stby power, which pitot probe(s) are heated?
Only the captain’s
When the ENG ANTI-ICE switch is ON,
Bleed air flows through the cowl lip anti-ice valve for cowl lip anti icing. Stall warning logic is set for icing conditions
Anti-ice stall warning logic
Anti-ice on (engine and/or wing) - icing logic
Anti-ice off (engine) - resets to normal, if wing anti ice not used
Anti-ice off (wing) - does not reset to normal
Bright COWL VALVE OPEN followed by amber TAI on the CDS after a short delay indicates
Cowl anti-ice valve fails to move to the position commanded by the switch
Can the engine anti ice system still function if all bleed switches are positioned off?
Yes, the cowl anti ice valve is positioned upstream of the bleed air shutoff valve
Wing anti ice valve closes automatically when
Applying takeoff thrust, and the lights will illuminate bright. Once weight is off wheels, the switch will move to the off position
Can wing anti ice still function if all bleed switches are positioned off?
No, the wing anti ice valve is positioned down stream of the bleed air shutoff valve
How are the anti ice valves powered?
Engine TAI - AC powered
Wing TAI - DC powered
Amber COWL ANTI ICE light indicates
An overpressure condition in the duct downstream of the cowl anti ice valve
Hydraulic system can overheat when
Low quantity
Overworking pump
Low fuel (heat exchangers in the main tanks rely on adequate fuel levels for cooling the hyd fluid)
Min fuel for ground operations of the electric hydraulic pumps
1675lbs in the related tank
Hydraulic pumps we have:
2 electric
2 engine driven
1 standby
1 PTU pump
Standby hyd pump can be turned on by
Flt control switch A
Flt control switch B
Alternate flap switch to Arm
Automatic operation
Purpose of auto operation of stby hyd system
Provide additional hydraulic pressure for the rudder during critical phases of flight during an engine failure
The standby hydraulic system will automatically initiate when
Loss of system A or B and
Flaps extended and
Airborne or wheel speed over 60kts and
Flt control switch A or B ON (normal)
Or the force fight monitor trips
Purpose of the LGTU (landing gear transfer unit)
Use system B engine driven pump to Supply volume of hyd fluid needed to raise the landing gear when system A engine-driven pump volume is lost
The LGTU is activated when
Airborne and
No 1 engine (RPM) drops below a limit value and
Landing gear lever is up and
Either main landing gear is not up and locked
Purpose of PTU (power transfer unit)
Supply the additional volume of hydraulic fluid needed to operate the auto slats and leading edge flaps and slats at the normal rate when system B engine driven hyd pump volume is lost
The PTU operates by
Using system A pressure to power a hydraulic motor driven pump which pressurizes system B hyd fluid
The PTU automatically operates when
System B eng pump hyd pressure drops below limits and
Airborne and
Flaps less than 15 but not up
Hydraulic system normal operating pressure
3000psi
Needs to be 2800-3500
Hydraulic system A:
Rudder
Ailerons
Elevator & feel
Thrust rev 1
Spoilers 2,4,9,11, ground spoilers
Landing gear
Nose wheel steering
Alternate brakes
AP A
PTU
(2-position tail skid, if installed)
Hydraulic system B:
Rudder
Ailerons
Elevator & feel
Thrust rev 2
Spoilers 3,5,8,10
Yaw damper
Flaps and slats
LGTU
Alt nose wheel steering
Brakes
AP B
Standby hydraulic system:
Stby yaw damper
Stby rudder PCU
Slats
Reversers
Rudder
AUTO FAIL light illuminates when
Loss of DC power
Controller fault
Outflow valve control fault
Excessive differential pressure over 8.75psi
Excessive rate of cabin pressure change +/-2000fpm
High cabin altitude above 15800ft
Amber OFF SCHED DESCENT illuminates if
The airplane begins to descend without having reached the preset cruising altitude
Outflow valve motors are controlled by
Auto system: 2 identical controllers, alternately sequenced as primary, control the primary DC motors
Manual: flight crew opens and closes using outflow valve switch; a separate DC motor powered by DC standby, drives the valve
Cabin altitude and cabin rate of climb gauges are powered by
Mechanically powered
Cabin altitude warning horn will sound at
10000 cabin alt
Passenger oxygen masks drop when
Cabin alt is at or above 14000 or
Passenger oxygen switch is placed to on
Left side wing body overheat can be caused by
A bleed leak in:
Engine pylon/strut
Air cond bay
Leading edge of the wing inboard of engine
Keel beam
Apu duct
PACK or PACK TRIP OFF means
A pack overheat occurs due to a high workload on the affected air cond pack; the respective pack valve will close
BLEED TRIP OFF light illuminates when
Excessive pneumatic temp or pressure is sensed. The respective bleed valve will close
The Trip reset button, as per the QRH, allows us to reset
Pack trip off
Bleed trip off
Zone temp
DUAL BLEED light illuminates when
The apu bleed air valve is open, and the position of the engine air switches and isol valve would permit possible back pressure of the apu. (The engine air bleed valve may not necessarily be open)
When dual bleed light is illuminated, thrust must be limited to
Idle thrust
RAM DOOR FULL OPEN lights are normally illuminated either
On the ground
Inflight with flaps extended
Ram air doors normally close after
Takeoff with the flaps up
Recirc fans operation in auto
In flight - left recirc fan operates if both packs are operating unless either pack is in high; right recirc fan operates if both packs are operating unless both pack switches are in high
On ground - left fan on unless both pack switches in high; right always on
If air in a supply duct overheats,
The associated amber zone temp light will illuminate and the associated trim air modulating valve closes
Isolation valve in the auto position
Open - any of the pack or engine bleed switches are selected off
Close - no pack or engine bleed switches are selected off
ALIGN lights flash on the IRS if
The irs has no position, a bad position, or the aircraft has experienced movement
ON DC light indicates
Within first 5 seconds of powering on, it is a normal self-test.
Afterwards, it indicates the irs has lost AC power and is on batt power
FAULT light indicates
The IRS has experienced a fault
DC FAIL lights indicate
DC power has failed because switched hot battery bus is not powered or
Battery has discharged or
Battery is in off position
EEC (electronic engine control) control channels
Each EEC has two independent control channels
Control channels alternate between each engine start or start attempt
EEC failure modes
Hard failure - manually selected to alternate
Soft failure - automatically switches to alternate
What may happen when the eec enters soft failure mode?
A thrust shortfall or engine exceedance may occur as the last sensed flight conditions are locked in and no longer sensing real-time information
ENGINE CONTROL light indicates
An engine control system fault exists. The light illuminates on the ground only; do not take off.
Amber REVERSER light could indicate
One or more have occurred:
Isol valve or thrust rev control valve is not in commanded position
One or more thrust rev sleeves are not in commanded state
Auto-restow circuit has been activated
A failure has been detected in synchronization shaft lock circuitry
After landing, REVERSER light illumination indicates
A disagreement between the reverser and the position of the lever
Full crew oxygen bottle
1850PSI
PASS OXY ON light indicates
A signal has been sent to the PSU (pax service units) doors to open
The flight recorder operates
On the ground with an engine running, or in flight anytime electrical power is available. (It is normal to see the flight recorder OFF light illuminated on preflight)
The left ignitor is powered by
The respective AC transfer bus
The right ignitor is used for engine start on the first flight of the day because
It is powered by the AC standby bus, and essentially does a check of our inverter and the ac stby bus
With the engine start switches in OFF, the ignitors are activated when
Eng start lever is in idle and:
An uncommanded rapid decrease in N2 occurs or
N2 between 57%-50% or
In flight, N2 between idle and 5%
Difference between GND and CONT
GND - start valve will open
CONT - start valve is bypassed
Difference between CONT and FLT
CONT provides ignition to the selected ignitor when engine is operating and start lever idle
FLT provides ignition to both ignitors
PSEU light illuminates when
On ground - a fault is detected in the PSEU or an over wing exit flight lock fails to disengage when commanded
In flight - inhibited from thrust lever advance to 30sec after landing
Things that could cause the takeoff warning horn to sound
Speedbrake not in down detent
Stab trim not in green band
Parking brake set
Flaps not in a position for takeoff
WHEEL WELL light during a fire test
On batt power, will not illuminate bc the wheel well is powered by ac transfer bus (#2)
Also does not illuminate during CA preflight lights test
Cargo Fire suppression system
The first bottle will discharge immediately, the second bottle will discharge 60min later. Weight on wheels will inhibit the discharge of the second bottle
Stabilizer Trim Override switch
If trimming in opposite direction of control column, stab trim cuts out. In the event of control column jam, the switch in the override position bypasses the cutout to restore power to the stab trim switches
STAB OUT OF TRIM light comes on when
The autopilot is connected and not trimming properly
SPEEDBRAKE DO NOT ARM light indicates
An abnormal condition in the auto speedbrake system or
After landing, wheel speed is less than 60kts, and speedbrake handle not down
Speedbrake use on landing with DO NOT ARM illuminated
Can be manually deployed
Conditions to set autobrake to RTO
Airplane on the ground
Thrust idle
Airspeed less than 60kts
Anti-skid operational
RTO selected
SPEEDBRAKE EXTENDED light illuminates when
Lever is beyond the armed position and trailing edge flaps extended beyond flaps 10 or radio alt less than 800’
Ways to disarm autobrakes
Move speedbrake lever to down detent
Advance thrust levers forward
Apply manual brakes
Position switch to off
