What are the electric power sources?
o 4 variable frequency engine starter/generator VFSG
o 2 variable frequency APU starter/generator VFSG
o 3 external AC power receptacles
o 1 RAT
o 1 APU battery
o 1 Main battery
o 3 flight control permanent magnetic generators
o 2 EEC permanent magnetic alternators
Where are the PMGs? refrence (power flow and load distribution)
Two on the left engine and one on the right engine.
What are the 2 distinct power distribution methods?
o Primary: Energizes High AMP loads from the electric buses
o Remote: Energizes low AMP loads from the RPDUs.
What is an RPDU and how many are they?
Remote Power Distribution Unit, powers 10 AMPs or less, And they are 17 RPDUs.
How many 235V power system buses are there?
4 buses, L1, L2, R1 and R2.
How do the generators power these main buses?
o With both engines: Each bus is powered by its engine generator.
o With one engine and the APU: the engine related buses are powered by the engine
generator and the other 2 buses by the APU.
o With external power: By the 115V external power through a power converter.
o With APU only: each APU generator powers 2 buses.
On Ground with only forward external power selected, what powers the 115V buses?
They are powered directly by external power. Then it energizes the 235V through the
converter.
With engines or APU running, what charges the 115V buses?
They are charged by the 235V buses through a converter.
What is the BPCU, and what does it do?
Bus Power Control Unit provides load management and protection and power transfer.
If it fails a second BPCU takes over.
What power sources can the A/C use for engine start?
APU, 2 forward external powers, and the other engine.
Aft external can be used to assist a start for which engine?
The R engine
How many starters are needed to start the APU?
1 starter only
How many starters are needed to start the engines?
2 starters
Are both APU generators required to maintain the electrical load in flight?
One or both are needed depending on the load.
What are the primary and backup power for the brakes?
The main is 28V bus system, and the backup is provided by the main battery.
Where are the external power receptacles located?
o 2 on the forward left fuselage
o 1 on the left fuselage aft of the wing.
How many ground sources are required to energize ground handling mode?
1 only
In flight, when will the RAT generator automatically deploy?
o Both engines fail
o All 3 hydraulic systems pressure is low
o Loss of all electric power to the CA & FO instruments.
o Loss of all 4 EMPs and a fault occurs in the flight control system on approach.
o Loss of all 4 EMPs and an engine failure occurs during T/O or Landing.
Which cockpit displays are powered during RAT operations?
Captains DU’s and Lower DU.
What major systems are not available during In-Air RAT Only mode?
o Flaps & Slats
o LNAVNNAV
o TCAS
o FMS predictions
o HF
o TAT
o TAP
o GPWS
o FMS thrust limit
o SATCOM
o Autothrotle
o Thrust reversers
o WX Radar
o HUD
o Transponder
What Equipment is energized in the In-Air Battery Only mode?
It energizes the same as In-Air RAT only mode, except for the center pitot heat.
How is load shedding determined by the Bus Power Control Unit BPCU?
o Load Inhibit: Inhibits loads that are not required at a certain time.
o Load Shed: Loads are shed in order of priority.
How can load shedding be monitored?
The electric synoptics show a list of shed loads, also the system pages also show the
shed items.
What does the APU battery power on ground?
APU start and NAV lights
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1. Limitations16
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2. Exterior Inspection20
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3. Memory Items11
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4 NON - NORMAL MANEUVERS21
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5. SYSTEMS22
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5.2 AIR SYSTEMS36
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5.3 ANTI-LCE, RAIN14
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5.4 AUTOMATIC FLIGHT31
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5.5 COMMUNICATION6
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5.6 ELECTRICAL37
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5.7 ENGINE, APU63
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5.8 FIRE PROTECTION27
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5.9 FLIGHT CONTROL58
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5.10 FLIGHT INSTRUMENTS, DISPLAYS0
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5.11 FLIGHT MANAGEMENT, NAVIGATION14
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5.12 FUEL22
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5.13 HYDRAULICS10
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5.14 LANDING GEAR10
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5.15 WARNING SYSTEMS24
