How much does the APU burn?
400 lbs per hour
APU - RUN light
- a. Flashes twice during start; means electronic control unit is satisfied with self test.
- b. On steady means APU is at operating speed.
APU - FAULT Light - (EICAS msgs: APU FAULT, APU FUEL VAL, APU FIRE)
- a. The APU has automatically shut down for an internal fault.
- b. APU fuel valve disagrees with the commanded position.
- c. Fire has been detected.
- d. Position switch to OFF to reset fault detection circuitry
APU - Select Switch
- a. OFF-closes the APU bleed air valve if open, initiates cooling cycle and shuts down APU when cooling complete. Resets auto shutdown logic.
- b. ON-opens the APU fuel valve and inlet door. Activates AC or DC fuel pump. Powers the APU controller and permits APU bleed valve to open the bleed switch when reaching operating speed.
- c. START - initiates automatic start sequence. Starter duty cycle - 3 starts in 60min
- d. Accidentally selecting OFF can be cancelled by selecting START again, as long as the RUN light is illuminated.
APU - Batteries required to stat?
- Requires 2 batteries to start
- a. Aircraft Bat - fire detection, fire protection, APU fuel valve, DC fuel pump.
- b. APU Bat-starter motor, air inlet door motor, APU fuel circuitry.
- c. DC fuel pump-BB. If you turn BAT switch OFF-causes APU shutdown after normal cooling cycle. Not recommended way to shut down APU as the result is loss of APU fire detection.
What is automaticaly activated when APU is producing electricity.
L fwd AC fuel pump-Ground Service Bus. Automatically activated when APU is producing electricity, even if pump switch is off.
APU - Cool down? How to cancel a shutdown signal?
- 0-120 secs.
- Nominally set for 60 secs.
- Do not turn BAT switch off until APU is Shutdown.
- If RUN light still illuminated, selecting START cancels shut down signal.
APU - Starter duty cycle
Starter duty cycle is 3 start attempts (maximum) followed by 60 minutes to let the temperature of the starter decrease.
COCKPIT VOICE RECORDER (CVR) - What does it Recorde?
- 1. Records any transmissions from the flight compartment through any audio control panel.
- 2. Records flight compartment conversations using an area microphone.
COCKPIT VOICE RECORDER (CVR) - How much does it store, and how do you erase it?
- Stores up to 2 hours of conversation/transmissions.
- To erase, must be on the ground with the parking brake set.
COCKPIT VOICE RECORDER (CVR) - How do you test it?
- Older control head: Hold the test button and check to see the needle deflects 4 times as each of the 4 channels are tested.
- Latest control head: Hold the test button for 5 seconds. The illumination of the green LED indicates a good test.
- Both control heads incorporate a X" jack for a headset so one can test the area microphone.
- Charging if in the OFF or ARMED position
- EMER LIGHTS Switch: .
- OFF: - prevents emergency lights system operation if airplane elec power fails or turned off.
- ARMED: -all emergency lights illuminate if airplane electric power fails or is turned off.
- ON: -all emergency lights illuminate. System is not charging. UNARMED (amber) light: Any time emergency lights not armed (i.e., sw in OFF or ON)
PASS OXY SWITCH
- 1. OFF-STATUS page displays #1 oxygen cylinder pressure.
- 2. ON-STATUS page displays #2 oxygen cylinder pressure.
15 Minutes - LED light
RAM AIR TURBINE - Automatic deployment
- Propeller-driven hydraulic pump Deploys automatically with dual engine failure (below 50% N2) to provide hydraulic pressure to C sys powered flight controls only.
- Arms at 80 kts.
RAM AIR TURBINE - Minimum speed for operation? Pressure?
- 130 kts minimum airspeed for proper operation.
- Green PRESS light means adequate pressure
- RAT pressure isolated from system pressure switch;will not extinguish SYS PRESS light.
RAM AIR TURBINE - Electrical power for deployment/stowing?
- Can only be stowed on ground. Can manually deploy at any time.
- HBB - manual deployment.
- BB - auto deployment.
ENG START PANEL - Valve light/Advisory msg/caution msg
- 1. VALVE light - start control valve not in commanded position. (open above 50% N2
- Advisory msg: ENGINE STARTER;
- Caution msg: STARTER CUTOUT
ENG START PANEL - Ignition selector
- a. BOTH - both igniters in each engine operate when directed by Engine Start selector, or engine anti-ice switches.
- b. 1/2 - selected igniter in each engine operates when directed by Engine Start selector or engine anti-Ice switches.
- c. #1 position - L engine uses L AC bus, R engine - R AC bus, defaults to STBY AC bus.
- d. #2 position - L and R engines use STBY AC bus
Engine Start Selector - GND
- i. APU to high pneumatic flow.
- ii. Left hydraulic demand pump sheds
- iii. Utility busses shed (for 1" engine started; respective bus sheds for remaining engine start).
- iv. Arms selected igniter(s)
- v. Opens start valve
- vi. Selector magnetically held in GND position until 50% N2 - spring loaded to AUTO
Engine Start Selector - GND
- i. Closes the start valve
- ii. APU returns to normal pneumatic flow.
- iii. Selected igniter(s) ON continuously with flap handle out of up, or engine anti-ice switches ON.
- iv. Selector releases to AUTO at 50% N2 and terminates engine ignition.
Engine Start Selector - OFF, CONT, FLT
- OFF - no ignition
- CONT - selected igniters operate continuously, no time limit.
- FLT - both igniters operate continuously regardless of ignition selector position. - No duty time limit.
FUEL Quantity ?not sure if this is right?
- Mains 40,668
- Center 55,675
- Wings total 81,336
- All 137,011.
- (Weights based upon 6.7 Ibs/gal)
APU Fuel Feed
- APU fuel is supplied from the L fuel manifold through an open APU Fuel Valve.
- APU fuel feed can be provided by any AC fuel pump supplying fuel to the L fuel manifold or by the L main tank DC fuel pump.
- FWD & AFT AC motor pumps in each main.
- Fuel pump switch ON is on, OFF is off.
- PRESS lights if pump output press is low.
Starting APU without AC power - FUEL
- One DC motor pump in L main for starting APU:
- a. Powered from ship's battery; BATT switch ON.
- b. Automatically started with the APU selector ON and no AC power available.
- c. No indications for flight crew of its output pressure.
FUEL - CROSSFEED
- CROSSFEED ON - crossfeed valve selected open
- CROSSFEED OFF - crossfeed valve selected closed
- CROSSFEED VALVE light - crossfeed valve not in commanded position.
- To CROSSFEED - CROSSFEED ON, low main off. "If it's low, make it glow," PRESS light glow that is.
FUEL CONFIG light - EICAS msgs: FUEL CONFIG, LOW FUEL
- a. Low fuel quantity of 2,200 lbs or less in either main, with EICAS msg LOW FUEL
- b. Imbalance between L & R main tanks of 2,000 +/- 500 lbs. (1800lbs 757)
- c. Center tank fuel pumps off with >1,200 lbs fuel in C tanks
Fuel imbalance (AOM Limitations)
2500 @ 48,000 lbs; linear reduction to 1500 @ 79,800 lbs.
load mains until full, then fuel center
Fuel Pump power source
- L & R Fwd wing AC fuel pumps crisscrossed with L/R AC so don't lose both pumps in the same wing with
- L or R AC failure. (Same as demand elec. hyds.)
- Max tank fuel temp 49°C
- Min +3°C above freeze point of fuel being used
Can the Center tank contain fuel without the main being full?
Up to 22,050 lbs of fuell provided C tank fuel wt. + aircraft ZFW doesn't exceed MZFW (266K) and CG limits observed.
Center Override pump PRESS light
- a. Inhibited with pump switch OFF
- b. illuminated when output press low with pump switch ON and respective engine running.
- c. illuminated with no fuel remaining and pump switch ON and respective engine running.
Center Override pump operation
- Inhibited < 50% N2
- Inhibit removed with fueling door open or respective engine is started
Fuel Usage I (No Center Tank Fuel)
- Use tank-to engine fuel for takeoff and landing with all operable main tank fuel pumps on and crossfeed valve(s) closed.
- Open crossfeed valve(s) for minimum fuel operations or to correct/prevent fuel imbalance.
Fuel Usage II (Fuel in Center Tank)
Use the center tank fuel for all operations with all operable boost pumps ON and crossfeed valve(s) closed until the center tank is depleted, then use FUEL USAGE I.
CTRL FUEL PUMP limitaions
- Intentional dry running of a center tank fuel pump (CTRL FUEL PUMP or CTR R FUEL PUMP message displayed on EICAS) is prohibited.
- If a center tank fuel pump fails with ample fuel in the center tank, accomplish the FUEL PUMP Non Normal Procedure.
- B767 aircraft with center tank fuel pumps deactivated (inop):
- No fuel may be in the center tank for dispatch except that which drains from the fuel line manifold into the center tank following each fueling operation. (See Chap. 4, Sec. 2; Fuel System Operations)
FUEL QUANTITY INDICATOR - Display, Temp, Total
- 1. Displays useable fuel in L, C & R main tanks in thousands of pounds.
- 2. Fuel temp from L main tank because it's the cooler of the two mains. The right main has two hydraulic heat exchangers; the left main has only one.
- 3. TOTAL is a separate calculation and not a summing of the L, C&R indicators; this figure is also sent to the FMC.