BOEING EXAM #3 QUESTIONS WITH
CORRECT ANSWERS
what is default position for utility relay box? - Answer-de-energised state contacts
route outputs from right aads to hiadc
purpose of hiadc? - Answer-receive inputs from aads and process pitot, static, temp
and angular displacement
operation of air data system? - Answer-2 ads which are hads and adp
hads is primary source that processes inputs and supplies sp
sp filters inputs to calculate wind speed, direction, fwd static air temp, long and lat
true airspeeds
sp sends this to dp and fmc
fmc routes static air temp, long and lat true airspeeds to wp
what does wp utilise hads info for? - Answer-to calculate optimum ballistic solution
for effective delivery of weapons
what functions does sp carry out for hads? - Answer-initiate and monitor probe
change commands
provide boresight data and commands
monitor fcr
when will sp change aads probe? - Answer-bit detects fault
excessive probe motion
angular rate below normal operating thresholds
movement of probe in yaw
where does sp true airspeed come from? - Answer-egi for 0-18kts
hads 18+kts
what info does adp receive? - Answer-air mass and temp from hads
it's own pitot and static transducers
inertial ground speed signals from egi
what inputs will adp use for indicated airspeed? - Answer-egi for below 40kts
blended inputs of egi and hads 40-70kts
hads for above 70kts
purpose of power output shaft speed/torque sensor? - Answer-signal for power
output shaft speed collected by front sensor sent to eecu
power output shaft torque data collected by rear sensor and 2 rear phonic wheels
sent to eecu
works by teeth of gear train going through mag field causing electrical currents in
sensor
,purpose of power turbine over speed sensor? - Answer-part of system to stop engine
when power turbine going too fast
works by teeth of gear train go through mag field causing electrical currents in
sensor
purpose of thermocouples and harness? - Answer-7 thermocouples in 2 separate
harnesses installed in holes around power turbine case
monitor temp of gas flow at inlet to power turbine
purpose of air turbine starter? - Answer-rotate gas generator through accessory
gearbox until reaches 36%Ng
consists of 2 sections-energy conversion and gear reduction
purpose of heiu? - Answer-supplied with low voltage and converts it to high energy
electrical pulses for engine start
purpose of long and short ignition cables? - Answer-connect heiu to spark igniters for
engine start
how does engine oil system work? - Answer-oil from tank goes to pump that houses
pressure pump and 2 scavenge pumps
then flows to oil filter housing
then to heat exchanger and back into accessory gearbox to lubricate the drives and
bearings and to the bearing chamber
2 scavenge pumps draw the oil from bearing chambers
return oil passes over 2 mechanical mag plugs
then returned to oil tank over electrical mag plug
purpose of engine air system? - Answer-primary is the main working element of
airflow through the engine
secondary airflow cools, seals and heats components within engine
what does engine fuel and control system provide control for? - Answer-fuel
management
rotor and power turbine speed
gas generator and power turbine over speed protection
fault detection
engine life cycle counting
what can engine fuel and control be divided into? - Answer-fuel feed/distribution
system
fuel control system
fuel indicating system
high pressure fuel pump operation? - Answer-metering valve changes flow of fuel to
spray nozzle
eecu controls stepper motors that rotate metering valve
eecu/pcl control fuel shut off valve
selected to off fsov opens to bleed off fuel pressure closing pressure valve and
stopping fuel to spray nozzle
, where do output signals to engine come from? - Answer-one control channel only of
the eecu but both channels share input signals
what are eecu main control functions? - Answer-on demanded start
flight position
control fuel flow
output of Nps
vanes
bleed valves
what does eecu do when start is selected? - Answer-powers fuel on/off valve
powers combined start and pressuring valve
powers heiu
what are the drive modes? - Answer-loaded
no load
what is output of Nps compared with? - Answer-PCL- allows ground idle or flight
Ng limits
TGT limit- respect to mechanical limits of engine
rotor acceleration control
purpose of over speed protection module? - Answer-prevent Ng and Npt over speed
shuts down engine if Ng exceeds 110% or Npt exceeds 115%
purpose of contingency mode? - Answer-raise engine limits for gaining max engine
power
auto selected if 25% torque split occurs
when is engine start aborted? - Answer-if light up not achieved within 20s
what is the max residual gas turbine temp for starting? - Answer-300 degrees
what is the starting limit? - Answer-750 degrees
purpose of training mode soft key? - Answer-used to practice for engine failure
can only be done to one at a time
reduces the Nf to 96%
how many wca are there? - Answer-10 warnings
37 cautions
27 advisories
when power is applied what eecu tests are performed? - Answer-pbit
cbit
purpose of hads? - Answer-sense and process omni-directional pitot, static and temp
inputs and provide calculated air mass data
CORRECT ANSWERS
what is default position for utility relay box? - Answer-de-energised state contacts
route outputs from right aads to hiadc
purpose of hiadc? - Answer-receive inputs from aads and process pitot, static, temp
and angular displacement
operation of air data system? - Answer-2 ads which are hads and adp
hads is primary source that processes inputs and supplies sp
sp filters inputs to calculate wind speed, direction, fwd static air temp, long and lat
true airspeeds
sp sends this to dp and fmc
fmc routes static air temp, long and lat true airspeeds to wp
what does wp utilise hads info for? - Answer-to calculate optimum ballistic solution
for effective delivery of weapons
what functions does sp carry out for hads? - Answer-initiate and monitor probe
change commands
provide boresight data and commands
monitor fcr
when will sp change aads probe? - Answer-bit detects fault
excessive probe motion
angular rate below normal operating thresholds
movement of probe in yaw
where does sp true airspeed come from? - Answer-egi for 0-18kts
hads 18+kts
what info does adp receive? - Answer-air mass and temp from hads
it's own pitot and static transducers
inertial ground speed signals from egi
what inputs will adp use for indicated airspeed? - Answer-egi for below 40kts
blended inputs of egi and hads 40-70kts
hads for above 70kts
purpose of power output shaft speed/torque sensor? - Answer-signal for power
output shaft speed collected by front sensor sent to eecu
power output shaft torque data collected by rear sensor and 2 rear phonic wheels
sent to eecu
works by teeth of gear train going through mag field causing electrical currents in
sensor
,purpose of power turbine over speed sensor? - Answer-part of system to stop engine
when power turbine going too fast
works by teeth of gear train go through mag field causing electrical currents in
sensor
purpose of thermocouples and harness? - Answer-7 thermocouples in 2 separate
harnesses installed in holes around power turbine case
monitor temp of gas flow at inlet to power turbine
purpose of air turbine starter? - Answer-rotate gas generator through accessory
gearbox until reaches 36%Ng
consists of 2 sections-energy conversion and gear reduction
purpose of heiu? - Answer-supplied with low voltage and converts it to high energy
electrical pulses for engine start
purpose of long and short ignition cables? - Answer-connect heiu to spark igniters for
engine start
how does engine oil system work? - Answer-oil from tank goes to pump that houses
pressure pump and 2 scavenge pumps
then flows to oil filter housing
then to heat exchanger and back into accessory gearbox to lubricate the drives and
bearings and to the bearing chamber
2 scavenge pumps draw the oil from bearing chambers
return oil passes over 2 mechanical mag plugs
then returned to oil tank over electrical mag plug
purpose of engine air system? - Answer-primary is the main working element of
airflow through the engine
secondary airflow cools, seals and heats components within engine
what does engine fuel and control system provide control for? - Answer-fuel
management
rotor and power turbine speed
gas generator and power turbine over speed protection
fault detection
engine life cycle counting
what can engine fuel and control be divided into? - Answer-fuel feed/distribution
system
fuel control system
fuel indicating system
high pressure fuel pump operation? - Answer-metering valve changes flow of fuel to
spray nozzle
eecu controls stepper motors that rotate metering valve
eecu/pcl control fuel shut off valve
selected to off fsov opens to bleed off fuel pressure closing pressure valve and
stopping fuel to spray nozzle
, where do output signals to engine come from? - Answer-one control channel only of
the eecu but both channels share input signals
what are eecu main control functions? - Answer-on demanded start
flight position
control fuel flow
output of Nps
vanes
bleed valves
what does eecu do when start is selected? - Answer-powers fuel on/off valve
powers combined start and pressuring valve
powers heiu
what are the drive modes? - Answer-loaded
no load
what is output of Nps compared with? - Answer-PCL- allows ground idle or flight
Ng limits
TGT limit- respect to mechanical limits of engine
rotor acceleration control
purpose of over speed protection module? - Answer-prevent Ng and Npt over speed
shuts down engine if Ng exceeds 110% or Npt exceeds 115%
purpose of contingency mode? - Answer-raise engine limits for gaining max engine
power
auto selected if 25% torque split occurs
when is engine start aborted? - Answer-if light up not achieved within 20s
what is the max residual gas turbine temp for starting? - Answer-300 degrees
what is the starting limit? - Answer-750 degrees
purpose of training mode soft key? - Answer-used to practice for engine failure
can only be done to one at a time
reduces the Nf to 96%
how many wca are there? - Answer-10 warnings
37 cautions
27 advisories
when power is applied what eecu tests are performed? - Answer-pbit
cbit
purpose of hads? - Answer-sense and process omni-directional pitot, static and temp
inputs and provide calculated air mass data
