B-767 Mysteries Revealed

BATTery switch ON, STBY PWR SELector to AUTO.

Hot battery, battery, standby AC and standby DC

• Standby ADI, airspeed, altimeter, and engine instruments. Left VHF (HF also if
• equipped) along with both comm heads. Left VOR, center ILS, and whiskey compass.
• (Capt's RDMI has no heading information yet because the right IRU isn't up yet)

AVAIL means external power has the proper phase and voltage

• Since the ground handling bus is powered (EXT AVAIL or APU), the cargo doors and
• handling system, as well as the auto refueling system, are powered and usable. The
• ground service bus could also be selected over to the ground handling bus (door 1L).
• Oh yeah, of course the AVAIL also allows you to select external power ON

A momentary FAULT light as the APU fuel valve opens

The left forward fuel pump (DC if AC is not available) starts up and the APU inlet door opens. All powered by the Ship's batterry.

The APU battery provides the cranking power and the control circuits.

All the standard stuff, Underpressure (oil), Overtemp (EGT), or Overspeed (N2).

ON DC lights will illuminate for a few moments, then they will extinguish and the ALIGN lights will illuminate. When ON DC is illuminated, the associated IRU is being powered off the Hot Batt Bus (DC) through its own internal static inverter (AC).

DC FAIL simply notifies you that the associated DC backup (static inverter) has failed. Anytime the IRU selectors are out of the OFF position, the inverters are hot. As long as AC power is still available, the IRUs will operate normally.

First, the ADC Warnings are tested. The OVSPD light and message will activate, along with both Master Waming lights and the siren. The warning test will shut down in about 2 seconds. Continuing to hold the test switch, the ADC instruments (Mach/Airspeed, Altimeter, and Vertical Speed) will begin winding up (increasing), then will display OFF (fault) flags. Releasing the test switch will return the ADC instruments to normal.

The VSI is driven by both the (associated) IRU and the associated ADC. If either are faulted (or still aligning), the VSI will be faulted. In this case, apparently theIRUs are still aligning.

All the stuff across the front of the quadrant. The parking brake is released, the stab trim is in the green band, the speed brakes are closed, and the flaps/slats are in the TO range.

Everything on the circuit tested OK for TO. (ie: not normal for preflight, eh?)

The gear is not down and a) landing flaps have been selected or b) the (left) RA is below 800 ft with either throttle at idle.

Each IRU provides its associated ball (blue/brown horizon thing in the ADI), heading (the numbers along the outside of the compass rose on the HSI), VSI, and opposite RDMI heading. These items will be missing if the IRU is not operating.

First step on the systems setup is to turn on the R ELEC HYD pump to pressurize the normal brake system.

The R pump PRESS and SYS PRESS lights and their associated EICAS messages will extinguish. The BRAKE SOURCE light will extinguish, and the brake pressure gauge will increase.

Alternate brakes are selected automatically anytime right hydraulic pressure is low and the alternate brake source (L on the 757, C on the 767) is available.

Normal brakes (r hyd sys) provides for antiskid per wheel with autobrakes. Alternate brakes (heavy hyd sys [L on 757, Con 767]) provide for antiskid per axle 'With no autobrakes.

Obviously, the RESV BRKS switch must have been selected on, which did 3 things. It opens a supply valve to provide the standpipe fluid, it turns on a pump (which caused the indications you're seeing) (R ELEC HYD on the 757, C #1 ELEC on the 767) to pressurize that fluid, and it closes an isolation valve to isolate that fluid from the main system (SYS PRESS light remains illuminated) for the brakes only.

The C #1 ELEC HYD PRESS light would be extinguished and the C SYS PRESS light illuminated.

On the 767, RESV BRKS and STRG additionally provides nose wheel steering not provided on the 757. However, the 757 provides antiskid per wheel with autobrakes whereas the 767 provides antiskid per axle with no autobrakes.

Loss of both the right and "heavy" hydraulic systems. Yes.

767: C=RESV BRKS and STRG

80 kts: 1) Autothrottle servos disengage (THR HOLD) 2) Autobrakes are armed for RTO 3) The RAT is armed for autodeployment (loss of both engines) and 4) Master Caution lights and beeper are inhibited.

Yes. The QTY light simply means low quantity.

Full time pumps on a 757 vs demand pumps on a 767.

In AUTO, the DEM pumps are activated by a) system pressure dropping to the demand level or b) anticipating a drop in system pressure (L or R sys: Fuel Control switch to Cutoff. C sys: activation of the gear, flap, or speedbrake handles).

No gyro sources until at least 1 IRU reaches alignment

The left flight instruments will be missing the ball (The blue and brown horizon thing on the ADI), heading (numbers on the outside of the compass rose on the HSI), VSI (an OFF flag is displayed), and the opposite RDMI (FO's HDG flag displayed).

6 [4 on the 767-200]. 4 [2] overwing escape hatches and 2 off wing slide pack doors

• 757: AIRlGND on GND plus Gnd Handling Bus.
• 767: Same except for manually operated Bulk Cargo door.

Illuminated until probes are being heated. Probe heat is activated with either engine N2 50%. Assuming no faults, all lights extinguish even though TAT probes aren't heated until AIRlGND relays in flight. Then of course, on the 767-200's only, there's the MACH PROBE and the ENG EEC PROBE lights that don't extinguish until both engines are running.

Not with any autopilot engaged. The STAB TRIM light tells me I'm commanding full speed trim (ie, yoke trim switches only) and I'm not getting full speed. 1 or maybe even both motors are failing to respond.

Autopilot disengages.

Yoke trim is inhibited with multichannel engaged (ie: below the 1500 ft autoland self test)

The stabilizer will trim and the autopilot(s) will not disconnect until they are no longer able to control the acft. Since the autopilots are engaged and aren't the source commanding the trim to move, the fact that it's doing something other than commanded will activate the UNSCHED STAB TRlM light, message, Master Caution lights, and aurals.

The SPOILERS light. With the spoiler panels being commanded for roll assist on only 1 hydraulic system, some of the panels failed to position as commanded and tripped the light and message.

• The simplest cause is that there's no pressure on the L HYD system. Otherwise, there's a fault in the system. At Hi speed/Lo speed the system is supposed to be in Limited/Full authority but something is faulted. During a fault, the system is supposed to drop to Lo speed mode (Full authority) and depressurize I hyd channel out of the
• rudder actuator pack to prevent structural damage at high speed.

Either throttle through the Reverse Interlock automatically deploys the Speedbrakes, whether during a Reject or if we forget to arm them during an approach.

Truck de-tilt (out of the tilted position) and throttles to idle.

Fault in the auto speedbrake arming system. Do Not Arm because they may inadvertently deploy in flight or they may not deploy on the ground. ie: We don't know what they're going to do

Yeah, Big Time.

The SPOILERS light means they're not doing what they're supposed to be doing. The AUTO SPDBRK light means there's a fault in the system and they may not do what they're supposed to do. The SPEED BRAKES light means I have them out with landing flaps selected, or if I'm below 800 feet.

There's a fault in the antiskid system and that will inhibit the Autobrakes.

The 767 has both outboard as well as inboard ailerons. The outboards operate similar to the Rudder Ratio system in that at Hi speed / Lo speed, the outboards lock! unlock to decrease / increase roll authority. If something faults in that system, you get a light

A single power source load shed (ie: both utilities and affected recircs [R only on the757, both on the 767])

Sure, get up another power source and it'll reset automatically. Or else, if the air/gnd relays are on the gnd, I have the option of manually resetting the load shed by cycling the mIL bus switches Off/On.

Low oil pressure or high oil temperature. Sitting at the gate, it's probably low oil pressure since the engines aren't turning.

The generator OFF light 'will illuminate as the generator breaker opens with the generator spooling down

Turn on the GND SERV bus switch at door lL.

The galleys themselves may have done some kind of internal load shedding. If you want to, you can try cycling the UTIL bus switches off I on to reset galley power

• 1st eng: Both utils (plus affected recirc(s),
• 2nd eng: Associated util (plus affected recirc)

On a single power source, you can only run 3 out of the 4 ELEC HYD pumps on the 767. Both airplanes will shed the #2 C ELEC HYD pump

Not until the acft is "Clean and Climbing" (ie: gear and flaps up) to prevent inhibiting the ADP (C DEM Pump).

• L Fwd PRESS light extinguished (for the APU) and the other 3 main pump PRESS lights illuminated. Both C tank PRESS lights extinguished (inhibited with switches OFF) and the FUEL CONFIG light illuminated (fuel in the C tank with the pump
• switches OFF).

The PRESS lights on all the mains will extinguish. As I switch on the C fuel pumps, the FUEL CONFIG light will extinguish. With the C fuel switches in ON position, their PRESS lights will illuminate because the pumps are inhibited until the associated engine is up and running (N2 50%).

Opens the start valve, initiates the load shed, anns the igniters (through the Fuel Control Cutoff Switch), and kicks the APU to high flow. Also, if somehow an engine bleed valve was stuck open, GND position would drive that valve closed and open the APU bleed valve.

Around N2 50%. AUTO provides selected ignition to continuous when the flaps are out or the engine anti-ice is on

Any time you want to, like maybe for.turbulence

CONT is selected ignitor, FLT is both ignitors regardless of selection

You'll get a Ka-Thunk out the back of the airplane as the RAT deploys (Hot Batt Bus) and no Batt Bus lights will illuminate.

Either above 80 kts or air/gnd relays in FIt. Loss of both engines (N2 50% speed cards) deploys the RAT to pressurize the primary flight controls on the C HYD system

No, the RAT is isolated to the primary flight controls only

Loss of "Normal" power to the emergency light battery chargers activates the interior emergency lights. Opening any armed door (overwing or entry) activates the exterior emergency lights on that side

Yes, the batteries are being charged anytime there's power on the acft.

Cabin altitude above 14000 ft.

The passenger cabin O2 doors are energized open and the masks fall out, and the passenger signs are illuminated. When a passenger pulls a mask, it pulls a firing pin that starts the chemical generators burning and produces oxygen

• The cargo boxes on the 757 are small enough that the cabin discharge air being drawn around the outside of the cargo boxes by the recire fans provides sufficient cargo box heating. Inside the cargo boxes are little "swirly fans" that keep the air in the box moving around to prevent any cold spots. Since it'll be a bit colder back next to the
• outflow valve, the "swirly fan" in the aft box is supplemented by a little electric heater. The cargo boxes on the 767 have the same cabin recirc air being drawn around them, but since they're so much bigger than the 757, cabin discharge air is supplemented by pneumatic bleed air (same concept as wing anti-ice) instead of the "swirly fans". 767 cargo heat is controlled by switches on the overhead panel and thus, can be considered to be "manual" as compared to the 757,"automatic".

Both auto controllers have faulted or you killed them by selecting MA.N.

Push a throttle up telling the pressurization system that I'm getting ready to go fly. With any door open (ie: hole in the acft), the outflow valve will end up fully closed trying to pressurize the acft.

At 10000 ft, the CABIN AL T warnings will activate. At 11000 ft, the outflow valve is hot wired closed. At 14000 ft, the passenger oxygen automatically deploys

set. 9500 ft to regain control of the outflow, 8500 ft for the CABIN ALT warnings to extinguish.

Location. If you're looking forward and trying to ignore the problem, you get a light in the face, or if you're looking up trying to deal with the problem you get a light in the face.

You could try raising the cabin altitude to flush the smoke out the back end of the acft

• Raise the LDG ALTon the on the pressurization panel, This will automatically raise the cabin altitude to whatever you select. If you want it to raise rapidly, simply increase the AUTO RATE. If instead you were to select MAN and drive the outflow valve open, the control is so sensitive it can easily get out of control. If cabin altitude
• were to reach 10000 ft, the alarms would trip but more importantly, if the cabin altitude were to reach 11000 ft, the outflow valve gets hot wired closed and traps ALL the smoke inside the acft. What kind of a disaster could that result in?

757 is open loop (ElE Cooling system exhausts into the passenger cabin). 767 is closed loop (self contained and does not vent into the passenger cabin). 757 controls are automatic, 767 control is manually selected.

Some kind of airflow problem and the book tells me to select STBY on the 767

REFRlG on the ground above 70° F, AUTO for all other normal operations.

E/E smoke clearance. E/E selector to OVRD on the 767 opens the SMOKE CLEARANCE valve and flushes the Flt Deck and Fwd/Main E/E Centers out the side of the acft.

With the REFRIG unit operating, the REFRIG Supply valve just forward of the Forward Cargo Door should be open as well as the Exhaust valve on the bottom of the fuselage.

For whatever reason, the REFRlG unit must have shut itself down. You have to cycle the E/E Selector to AUTO then back to REFRIG to reset the unit.

The GND CREW CALL HORN gets activated by an E/E Cooling system OVHT light or by the IRUs dropping to ON DC while on the ground (ie: AC power removed while any IRU is not OFF).

Might be due to an E/E OVHT. Normally, all these indicator lights bum 28 volts but, if you select the IND LTS to DIM you hook some resistors into the circuits that bring the voltage down to 12 volts instead. These resistors get kind of hot and are located pretty much everywhere there's indicator lights. If you get an E/E OVHT, the system will automatically cut these resistors (heat generators) out of the circuit (thus your lights go full bright).

The valve is closed, regardless of switch position

No air pressure, back pressure from another source (ie: ISOL valve left open), or system protection due to an Overtemp condition

When there is no ENG BLD source available to the center pneumatic duct plus anytime either engine start selector is in GND

Besides just isolating the L & R ducts as on the 757, the 767 is designed to always provide a protected air source to the ADP

• On the 767 -
• HI STAGE=OverTemp,
• BLEED=OverPress,
• DUCT LEAK=Duct Leak.

The OverTemp protection closes the ENG BLD valve (which can then be reset).

Nothing more than the light and message illuminate. The book tells you to shut off all the air to that side and don't attempt a reset

Same thing that an OFF light on the Eng BId valve would tell you. Simply that the valve is fully closed.

Could be a pack auto controller fault, could be a pack outlet overheat, or a pack compressor overheat (in which case system protection will also close the pack valve ie: both lights

The book tells you to push the PACK RESET switch. A controller fault will not reset and the book tells you to select over to the Standby Controller (N, C, or W). A pack outlet overheat is indicated by an INOP light and will reset. A pack compressor overheat will also reset and is indicated by an INOP light plus also, once system protection kicks in and shuts the pack down, a PACK OFF light.

Drives the pack outlet to (N) about 75°F, (C) full cold, or (W) full hot

The coldest temperature requirement. In this case, about 70.

Could be an overheat in the trim air duct for that zone, a fault in that zone channel, or maybe someone just felt like switching that zone off

Since that zone is "out of the loop" now that it's INOP, the packs will be driven to the next coldest requirement, in this case 75

80 is the next coldest requirement.

Turning off the TRIM AIR switch or a trim air controller fault.

Apparently, the Trim Air controller is kapoot. If you turn OFF the TRIM AIR switch, the packs drop to the default temperature of75

To save fuel. By using the recircs to provide airflow across the passengers, we're able to reduce the pack flow which reduces the bleed load on the engines.

Cabin discharge. Both recirc fans are picking up the air being discharged from the forward cabin. The right recirc is also picking up discharge air from the aft cabin

• 1) Load Shed: Since the recircs draw so much power but aren't very essential, they're powered off of the utility buses (except for the L recirc on the 757 which is powered off the L main AC) so any type of load shed will also depower the recircs.
• 2) Cargo Smoke: Since they recirculate air back into the passenger cabin, you don't want them dumping smoke in there. If smoke is detected near the recire fan pickups (ie: around the outside of the cargo compartments), they get inhibited. Arming the fwd cargo fire switch inhibits both fans, aft cargo fire switch inhibits the R recirc.

Since there are only 4 sources of air into the mix manifold (2 packs and 2 recire fans), if any source is lost, the surviving packrs) will go to high flow to make up for that loss (If the L recirc is inop, the L pack goes to high flow; if the R recirc is inop, the R pack goes to high flow; or if one paek is inop, the other goes to high flow).

Sure. Since high flow increases the bleed load on the engines (thus reducing thrust), high flow is inhibited anytime thrust is needed more than passenger comfort (from the increased bleed), ie: flaps out (takeoff or go around), additionally (767 only), if engine anti-ice is on, or (gee whiz) if wing anti-ice is being used off of a single bleed source.

The F/D signal comes from whichever FCC is selected on the INSTR SOURCE SEL panel. -ormally, the Capt is set to the L, and the FO is set to the R, but you can choose whichever FCC you want (L, C, or R) to provide your F/D. (Remember on UAL's configuration, an FCC is restricted to EITHER coupling to its autopilot servos OR providing F/D signals).

• Same failure indications except nothing left to recover by selecting ALTN FMC. I've lost LNAV and VNAV, so about the best thing to do is select over to HDG SEL and FLCH and navigate the airplane either on radar vectors or pull out a map and start
• dialing up some VORs (Ohhhh Noooool).

• 1) Both screens (ADI & HSI) going blank would indicate a symbol generator failure. (If just I EFrs screen dies, there's nothing to do, the screen is dead.)
• 2) Getting a fault flag for your LOC or GS receivers.
• 3) Getting a fault flag for your RA recei ver
• Swapping to the center symbol generator (EFI to ALTN) would recover the ADI and HSJ screens and swap to the C ILS receivers and the C RA receiver.

There's only a few things that'll affect the ASA. Each autoland channel has to have an FCC, an IRU, a power source, an ILS and a RA receiver. The only stuff not monitored by EICAS are the ILS and RA receivers. Swap to the C SG (EFI to ALTN) and you should find your problem.

I'd lose the attitude ball (ADI horizon) and get an ATT fault box on the ADI, I'd lose the numbers on the compass rose and get a HDG fault box on the HSI, I'd get an OFF fault flag on the VSI and a HDG fault flag on the opposite RDMI.

No. If I've lost an IRU, I've lost 1 autoland channel. NO LAND 3 will be latched into the ASA

I'd get OFF flags in the MACHI ASPD indicator, an OFF flag in the ALT indicator, and an OFF flag in the VSI (Note that the VSI gets instantaneous information from the IRU and trend information from the ADC).

2, 3, 3, 2. If there's 2 of something and you select ALTN, you go to the opposite. If there's 3 of something, ALTN gives you the center.

RTO

R Hyd system pressure (normal brakes), antiskid, and an IRU for deceleration rate.

That you either have low oil press on that engine, or that there's a high differential pressure across the oil filter

Any situation that would prevent displaying the primary engine instruments on EICAS. Maybe something like loss of both EICAS screens or both EICAS computers, or maybe even something like loss of all AC (Remember all these CRT's are AC powered).

Each altimeter light illuminates when approaching (900-300 ft) the Mep altitude. The ALT ALERT light illuminates when you're busting (300-900 ft) the MCP altitude

Turning the A/T ARM switch OFF, punching the AT disconnect buttons on the throttles, Loss of power to either EEC (Engine RPM spools below 10% N2 and the PMA's can no longer power the EEC's), taking a reverser through the interlock, or a fault in the system

Punch the A/T disconnect switches (on the throttles) twice

That there's either a fault in the engaged mode of the autopilot, or that you're exceeding the capabilities of the autopilot

To look down at the CDU scratch pad 'cause there's a message there

Get the cabin altitude down below 8500 ft

It means there's a fire on the acft, could be an engine, APLJ cargo, or wheel well fire. The light will only extinguish when the fire's out.

Running either engine up towards power with less than takeoff flaps, the speedbrakes extended, the Stab Trim not in the green band, or the parking brake set.

Either selecting landing flaps (25/30) at any altitude without a landing gear or descending below 800 ft RA without a landing gear with either throttle at idle.

Push the yoke disconnect button twice.

Slow down below Vmo /Mmo .

To inhibit the GPWS cautions if we're deliberately going to be coming in under the glide slope (ie: maybe making a non-precision LOC approach on an ILS).

The primary stuff (messages and primary engine instruments) would shift to the lower screen and the secondary stuff would be displayed in compacted mode.

That's the selected EPR limit (TO, D-TO, CLB, CRZ, CON, or GA)

The maximum available EPR for the current temperature and pressure altitude.

Start limit. Once the EGT rolls back during a start, the red mark disappears.

The Alternate flap system is electric instead of hydraulic, and it is very slow (about 1/4 speed). The Alternate system loses all the protection modes, ie: trailing edge asymmetry detection, flap load relief, and (757 only) Autoslat extension.

To silence the GPWS alarms anytime we're landing with less than landing flaps (25/30).

Anytime I'm landing with less than 3 gear (maybe ditching or a hung gear)

On the 767, when you take the gear handle UP, the gear and doors come up and the doors are latched. When you take the gear handle OFF, the stuff depressurizes and the gear settles down onto the doors.

On the 767, it takes C HYD SYS pressure.

When you flip the ALT GEAR EXT switch on the 767you're activating some electric solenoids (STBY DC BUS) that release the door uplocks and the whole mess falls out.

The gear handle lock solenoid failed to release for some reason (maybe the truck didn't tilt normally after takeoff). Pushing the LOCK OVRD will allow you to raise the gear handle. The gear should raise OK but you should expect some noise as the mains slide against the gear doors during retraction.

Both light bulbs in the LEFT green socket are inop. Do an indicator light test (button on overhead panel) to confirm this. If the gear was in fact not down, there are several other sensor/indicator circuits that would be giving you a GEAR DISAGREE Caution, plus once you descended below 800 feet RA with a throttle at idle, a GEAR NOT DOWN CONFIG Warning.

The real difference is location. The thermal loops (gas filled tubes that, as temperature increases, pressure increases) that trigger the fire alarms are located around the engine core, specifically around the accessory case and the fuel manifold. The thermal loops that trigger the overheat alarms are located up in the pylon around all the pneumatic ducting.

Engine fire and overheat detection (as well as APU fire detection) is provided by thermal loops, whereas cargo fire detection is provided by optical smoke sensors. Basically, a fan pulls air out of the cargo compartment through a box with a light beam in it. If the beam doesn't scatter, obviously there's no smoke in the airflow. If the beam scatters, then the cargo fire alarms are activated. The airflow then dumps right back into the cargo compartment.

Thermal loops (Eng Fire/Ovht and APU Fire) are continuously monitored, ie: if a loop faults (cracks), the pressure in the loop drops and the control card reconfigures to single loop operation. When it does, I get a STATUS message indicating the bad loop. Optical sensors (Cargo Fire) are only monitored when there's a power-up or manual test (push the FIRE/OVHT TEST button). If a sensor goes bad (LED burns out), it's not detected until another test is performed and thus, the control card doesn't reconfigure to single loop operation (ie:you really can't get a cargo fire indication until you push the TEST switch and reconfigure the control card).

It's only monitored during a manual test and it's single loop only. The loop is mounted along the top (ceiling) of both wheel wells so it's really only sensing anything when the gear's in the well

Pitch and Roll modes both come up in TO. The AFDS mode comes up in FD.

TO Roll mode "snapshots" the ground track at nose gear extension and provides guidance to maintain that until I select another roll mode. For a normal departure, TO Pitch mode provides pitch guidance to maintain V?+15. In the event of a VI cut, TO Pitch mode maintains the existing airspeed to a minimum of V2 and a maximum of V2+15.

The basic default pitch and roll modes are VIS and HDG HOLD. When a FCe is activated in flight, it snapshots the existing vertical speed (and the VIS window opens to display that speed) plus it rolls wings level then snapshots the existing heading (Gee whiz, this heading doesn't really get displayed anywhere).

Flaps out of the closed position or as capture

When the third autopilot gets armed, ie:select APP and arm the other 2 autopilots

Below the 1500 ft RA self test

FLARE and ROLLOUT armed (white) on the ADIs. Also a green bar (LAND 3 or LAND 2) on the Autoland Status Annunciator.

The glide slope bug will disappear, then a few seconds later, I'll get a yellow bar through GS pitch mode and an AUTOPILOT Caution and beeper.

Go Around

The right generator picks up the left and center buses (drops off the battery and the inverter) and the ASA downgrades to LAND 2 / NO LAND 3.

Below 200 feet, the right bus tie won't allow the right generator to pick up the left bus, the center buses stay on the battery and the inverter, and there is no downgrade on the ASA (ie: no distracters do\VI1that low). Basically, the only thing that happened is that the left bus died (ie: upper EICAS plus some other stuff). However, you have to remember that the autothrottle gets powered off the left side so I'll get an AfT DISC Caution and so I have to manually bring the throttles off in the flare.

280 / 240 kts

The Battery Charger receives its power from it.

• AC Bus - loss of the flood lights
• DC Bus - loss of the standby altimeter

• 1. 2000 lbs main takn imbalance
• 2. 2200 lbs or less in the main tanks
• 3. 1200 lbs or more in the center tanks with center fuel pumps off.