Collection of past Orals Flashcards
What happens if a power generating source fails?
Bus ties automatically connect to provide no system degradation
Can a single pack provide adequate temp control and pressurization?
Yes: up to FL310
What monitors and controls the IDG’s?
Each has a generator control unit (GCU)
Where are the Primary Ejector Pumps located?
In the collector tanks
How many different ways can fuel be supplied to the APU?
- DC Fuel Pump (tank 2)
- AC Fuel Pump (tank 2)
- Tank 2 ejector pump
- Tank 1 ejector pump via X-Feed
- Tank 1 AC Fuel Pump via X-Feed
Will the APU automatically shutdown if speed and acceleration rate isn’t reached in the starting cycle time?
Yes
Explain what happens in Hyd System 2 that allows us to safely conduct a single engine taxi with only Engine 1 operating?
If in “AUTO” (and only engine 1 is operating) upon releasing the parking brake ACMP 2 will activate to provide hyd power for nose wheel steering and the inboard brakes.
What happens if smoke is detected in the recirculation bay?
- Both recirc fans deactivate
- Cargo recirc fan deactivates
- Cargo Outflow Valve closes
What is min. airspeed for the RAT?
What happens if speed drops below that value?
130kts or else Load shedding occurs below this speed
If “OFF” is selected on the ground at what point will the anti-ice system become automatic?
1700 ft. AGL
or
2 minutes after takeoff (whichever happens first)
What is an SPDA?
An electrical load-mgmt unit powered by the ICC’s that distributes electrical loads to aircraft systems according to distribution logic.
What sources are used for aircraft anti-icing and de-icing?
- Bleed air heat
- Electric heat
What uses electric heat for ice protection?
- Pitot-static system
- Windshields
- Water lines
- Pressurization static port
What uses bleed air for ice protection?
Engine lips
3 outboard slats
What airplane systems have fire detection and protection?
- Engines
- APU
- Cargo Compartments
- Lavatories
What model PowerPlant is on our Ejet?
General Electric CF34-8E5, High-Bypass, Dual Rotor turbofan
Describe N2 spool?
10-stage compressor (gas generator)
2-stage HP turbine
What is the purpose of the scavenge pumps?
Maintains fuel level in the collector box
When will the “FUEL 1(2) LO LEVEL” EICAS be presented?
660 lb. of fuel remaining in the associated tank
What is the purpose of the DC GPU receptacle?
For APU start when BATT 2 is either:
Less than 22.5 VDC
or
Colder than -20 degrees
Describe the Engine and APU fire detection system?
Engine: 8 pneumatic fire detectors (2 loops) per engine
APU: 2 pneumatic fire detectors (2 loops)
What does the RAT power?
AC ESS BUSSES
Which powers:
- AC STBY BUS
- TRU ESS: directly powering DC ESS BUS 3 (which powers DC ESS BUS 1 and 2 through ETC 1 and 2)
What components power the DC system?
2 NiCad batteries
3 Transformer Rectifier Units (TRU)
DC GPU receptacle
What components are protected from Ice and Rain?
- Engine inlets
- Wing leading edge
- Smart probes
- Windshields
- Water and Waste drain systems
What happens when a cargo extinguishing button is pushed and smoke has been detected?
- High-rate bottle discharges immediately
- Low-rate bottle discharges after 1 minute if the airplane is in flight
- if airplane is on the ground (WOW) the Low-Rate bottle will not automatically discharge
What manages the electrical system?
4 Integrated Control Centers (ICC’s)
2 Secondary Power Distribution Assemblies (SPDA’s)
Describe in detail the normal engine start sequence?
N2 parameters
- 7%: Ignition
- 20%: Fuel Flow
- 20% + 5 seconds: Light Off
- 50%: IGN Cutoff
- 50%: Starter Cutout
When will the crossbleed valve automatically open?
- Only one side bleed source is available
- Eng 2 start in the air
- Eng 1 start in the air (if APU is not avail)
What is the primary purpose of the AC generators?
To power the AC busses and AC ESS Bus which:
Power the 3 Transformer Rectifier Units (TRU’s) 1 2 and ESS
Can a single bleed source power both packs?
Yes: through the crossbleed valve
How many Hyd. systems are on the airplane?
3 independent systems
Hyd 1, Hyd 2 and Hyd 3
How many hyd pumps are on the airplane?
6 total:
2 Eng driven pumps
4 AC motor pumps
What charges the batteries?
Any AC power source
What is the primary use for APU bleed air?
- ECS on the ground
- Engine starting on the ground
- Electrical source
During flight can the low-rate bottle be discharged before the minute is up?
Yes by pushing the extinguishing button again.
What is the primary purpose of Hyd sys 3?
Back-up for the Flight Controls
Is the ice protection system automatic?
Yes under normal conditions
What happens if there is a single bleed source failure?
The crossbleed automatically opens
How do you shutdown the APU immediately?
-APU emergency stop button -No 1-minute cool down period
What is the purpose of the Hyd system 3 accumulator?
Temporarily provides hydraulics to the flight controls during an electrical emergency. (from the beginning of RAT deployment until AC ESS Bus powers the AC pump 3A)
Can cargo extinguishing be used if no smoke is detected?
Yes. The high rate bottle extinguishing button must be pushed twice: -once to arm the bottle and once to discharge the bottle. -The low-rate bottle automatically discharges after one minute if in flight.
Describe N1 spool?
-Single-stage fan -4-stage LP turbine
How many ice detectors must be working to have icing detection?
One There are two for redundancy
How does the IDG maintain a stable power output?
A constant speed drive (CSD) attaches the IDG to the accessory gear box
What cools the pre-cooler?
-On Ground: N1 fan -In Flight: N1 fan or Ram air
How do you know a GPU is connected and ready to provide electricity?
-GPU button displays AVAIL -GPU icon displayed on synoptic page -Once GPU button pushed in “IN USE” is displayed
Where is fuel tank temp taken?
Left wing tank (-40 C min)
What events will cause an automatic shutdown of the APU IN FLIGHT?
-Overspeed -Underspeed -FADEC critical fault
When are ECS packs recovered?
Thrust Levers NOT at MAX and Airplane is 500 AFE with both engs operating -Airplane is >9700 ft. MSL with one eng operating
What is the purpose of the DCMP?
Used for APU or eng start if AC power or the ACMP is not available.
When does the RAT automatically deploy?
If both AC buses lose power inflight (electrical emergency)
What is normal pressure for any engine operation?
about 45 psi
How many networks make up the electrical system on the airplane? Why?
-2 independent networks -Redundancy and fault isolation
If “ALL” is selected on the ground at what point will the anti-ice system become automatic?
1700 ft. AGL or 5 minutes after takeoff (whichever happens first)
What is the fuel source for the APU?
-Right fuel tank -Left fuel tank through the Crossfeed valve
What happens if the APU EMER STOP button is pushed after a fire has been detected?
-APU shuts off immediately without a 1-minute cool-down -APU fuel SOV closes -APU FIRE EXTG button illuminates
What is the purpose of the forward cargo compartment recirculation fan shutting off and the ventilation outflow valve closing when smoke is detected?
-Prevents oxygen from entering the compartment -Prevents Halon agent from escaping into the aircraft’s cabin
If an IDG is manually disconnected can it be reconnected by the flight crew?
No. This is a maintenance function
What compressor stage is bleed air tapped for anti-icing operations?
10th High stage valve (HSV)
Can the APU shutdown be cancelled?
Yes: by moving the START switch back to “ON” before the 1-minute cool down is over.
What is the Normal AC Electrical Priority?
Onside (IDG) Inside (APU) Outside (GPU) Cross-Side (Opposite IDG)
What events will cause an automatic shutdown of the APU on the GROUND?
FOULFO -FADEC critical fault -Overspeed -Underspeed -Low oil pressure -Fire -Overheat
What does the overheat detection system (ODS) observe?
-Eengine bleeds and packs -APU Bleed -Plumbing For the wing & Eng anti-icing systems
What happens if a channel fails in the AMS controller?
The remaining channel is able to control the entire AMS.
Will the APU automatically shut down if a fire is detected?
Only on the ground
What fuel pump is used for APU start?
-Batteries “ON” only DC fuel pump in right tank -AC powered airplane ACMP 2 -Right engine running Ejector fuel pump
How are the engines and APU protected from fire?
-Engines 2 Halon fire bottles -APU 1 Halon fire bottle dedicated to the APU only
What’s on DC Hot Bus 1?
-Eng 1A/2A Fire Extinguisher -Eng Fuel Shutoff Valve 1 -Hyd Shutoff Valve 1-Eng 1 oil level indication -Courtesy/Service Lights -DC Ceiling Lights
What is the min battery voltage to close the battery bus-ties?
18 volts
In manual mode will the cabin depressurize on landing?
No
Will the APU fire extinguisher automatically discharge?
No
What will happen if batteries are turned OFF during the 1-minute cool down period?
The APU will shut down immediately
What is on the AC STANDBY BUS?
Eng exciters 1A and 2A
What happens if the wiper is operated on a dry windshield?
-The wiper will stop -To reset wiper move switch to “OFF”
How many igniters activate for engine start?
-Ground…1 igniter (switch in AUTO) -Flight…2 igniters (switch in AUTO)
Can one bottle be used for one compartment and the other bottle for the other compartment? (cargo compartment)
No. Only one compartment may be selected (FWD or AFT)
When will the PTU automatically activate?
During T/O and LDG with flaps >0 IF -Eng 2 fails OR -Eng Driven Pump 2 fails
Can engine bleed air flow-back to the APU?
No. A check valve prevents flow-back.
What kind of APU is on the aircraft?
Sundstrand APS 2300
If the airplane is using the GPU and the APU is started what should the pilot be sure to do?
Remember to deselect the GPU button before the next GPU connection
How long will the aircraft’s batteries last with no recharging?
Approx. 10 minutes