Powerplant Flashcards
What is in the engine output shaft assembly?
A Sump #1,2,3 Bearings
Engine cable colors?
Green - Cockpit indication
Yellow - Power (DECU) and Control (HMU)
Blue - Torque and overspeed sensors
Fuel bypass parameters?
30 micron
18-22 psid sensor closed
8-10 psid button pops
What does the engine fuel boost pump pressurize fuel to?
45 psi
When does the fuel pressure switch open?
Normally closed
Normal ops - opens when pressure increases to 10 - 11 psi
How does the oil press transmitter receive power? Where is it measuring oil from and how?
ELC? 10Vdc?
Differential pressure between B sump scavenge and oil pressure in the accessory section
Oil filter parameters? Bypass?
3 micron Valve 80 psid across the filter Red button pops at 44-60 psid Bypass switch 60-80 psid - SP before bypass Thermal lockout 100-130 F
Scavenge lines per sumps?
A = 2 B = 1 C = 3
Why is there a B sump check valve?
Prevent flooding to B sump during shutdown.
When does the cold oil relief valve open? where does it go?
120 - 180 psi
Returns to AGB?
During emergency operations, what bearings are lubricated by which sumps?
1-4 from A and B
Oil cooler relief valve opens when?
22-28 psi
Why is there no emergency oil for C sump components? or AGB?
AGB and C sump components can operate 6 minutes with residual oil.
How do the engine firewall lovers work?
28 Vdc energized solenoid in directional control value, allows IPAS to closed the lover assembly.
Where is the turbine speed control unit? Wired to?
2 Aft Avionics Bay ?
Hughes valve name?
Inlet Anti-Ice valve
GE valve name?
Anti-ice and Start Bleed valve
When does the start bleed valve open?
During engine starts and low power settings
What does the GE valve provide air to?
5th stage bleed air to swirl vanes, de-swirl vanes, nose splitter, and IGVs
GE high power operations?
(High power) 28vdc energizes solenoid that allows air pressure to move a servo that overcomes spring pressure.
(Anti-ice) SP commands ELC1/2 to de-energize solenoid, spring opens valve.
Where does the ENG CHOP msg come from?
Switch - SP - Relay (Utility Relay Panel) - DECU/TQ speed control - SP - EUFD
(COL) What areas are monitored by the Fire Detection/Extinguishing System?
(Aft area) - Mast base support struts, Heat exchangers
Engines and APU
Describe the overheat detectors
Alarm switch / Monitoring switch
Pressurized tube with helium gas
When does the alarm switch close?
Approx. 350 degrees (Hydrogen expands)
When does the monitoring (integrity) switch close?
40 psi - when tube looses pressure the switch closes (Helium leaks)
(COL) What is the only fire message displayed on the EUFD?
DECK FIRE
What does selecting fire detection test 1 test?
28Vdc
Integrity Switch (3 overheat detectors)
Aft flame detectors
Amplifiers
What does selecting fire detection test 2 test?
28Vdc Alarm switch (3 overheat detectors) Fwd flame detectors Amplifiers Continuity circuit on all squibs (DISCH lights)
How are the crossfeed valves controlled in the event of a fire?
corresponding FIRE button via battery bus
How many overheat detectors are on the aircraft?
3
How many flame detectors and amplifiers are there?
6 detectors / 3 amplifiers
What does pressing the ENGINE FIRE button do?
Shuts of crossfeed valves (FIRE) button via battery power to off position
Engine louver close via battery bus to actuator
Bleed air louver actuates when battery power is removed
APS blower and heating values shut down/close - SP - DECU (MUX)
Removes Master caution and audio
Squibs are armed (switch determines which one)
DISCH lights are illuminated (if squib has not failed)
RDY light indicates tasks are complete
What does pressing the APU FIRE button do?
Shuts of APU fuel boost pump (and APU)
Closes LCV
APS blower and heating values shut down/close - SP - DECU (MUX)
Removes Master caution and audio
Squibs are armed
DISCH lights are illuminated (if squib has not failed)
RDY light indicates tasks are complete
How are the flame detector amplifiers powered?
ENG1 = CBP1
ENG2 and APU = CBP2
Overheat detectors operation?
Alarm switch (inner / hydrogen) normally open (6" or more) Integrity switch (outer / helium) normally closed
What bus is the LSC on? What components does it receive inputs from in fire operations?
Battery bus
SP, Fire/Ext panel, Amplifiers
What will cause a DISCH light not to illuminate?
Bottle is not intact
Squib has failed
