DSC Landing gear Flashcards
What controls the landing gear ?
2 LGCIU (landing gear control and interface unit)
What is the switch between LGCIU happening ?
After the full RETRACTION of the landing gear
When is the landing gear safety valve active ?
Speed more than 260kt with data from ADR1 or ADR3
What HYD power the landing gear ?
Green
To which LGCIU is connected the Landing gear indicator panel ?
LGCIU 1
From which LGCIU does the GPWS receive data ?
LGCIU 1
When does the red arrow next to the landing gear lever illuminates ?
when A/C in landing config and gear not down lock
What HYD system power the NWS and which computer controls it ?
Yellow
Controlled by the BSCU
When does the NWS stop being connected to the rudder ? Hand wheel ?
above 130kt
Above 80kt
What are the brakes systems on the A/C ?
Normal brakes => Green HYD
alternate brakes => Yellow HYD
When does the switch between the BSCU channels occur ?
When the landing gear is selected DOWN
What controls the antiskid ?
When does it become available?
BSCU
>20kt
What controls the alternate braking ?
ABCU (alternate braking control unit)
What are the different type of alternate braking available and how are they controlled ?
- Alternate braking with antiskid (braking controlled by ABCU and antiskid by BSCU)
- Alternate braking without antiskid (braking by ABCU)
- Alternate braking without antiskid on accumulator (ABCU)
What info is used for the antiskid ?
Ref speed from BSCU
BSCU gets speed from ADIRS 1,2 or 3
What computers are required for the autobrakes to work ?
At least two SEC operative
What do you need to be able to arm the autobrakes ?
- green HYD
- Antiskid
- at least one ADIRS
- no failure in braking system
What is the delay after the spoiler for the autobrake to start working ?
2sec
What is the target deceleration rate for the autobrakes LOW, MED?
2 m/s² low
3 m/s² Med
When will the autobrake trigger on landing ?
When ground spoiler deploy so:
- Ground spoiler armed: Both main gear on ground and both thrust lever idle or one at reverse other below MCT
- Ground spoiler not armed: both main gear on ground and reverse on at least one and other below MCT
What HYD system power the park brake ?
Yellow
How long can the park brake be maintain for ?
12h
What are the main operational consequences of loosing LGCIU 1 + 2 ?
Loss of AP 1+2 and ATHR => Raw data
CAT I
No gear retraction due gravity extension => Fuel burn
No reverser
What happens for the gear doors with the gravity extension ?
they remains open
What is the approximate increase in fuel brun with the gear extended ?
180%
When do you expect to see the DECEL light when using autobrake
when 80% of the selected rate is achieved
When might you not see the DECEL light on landing with autobrake ?
Decel rate not achieved due slippery rwy
What information is shown on the triple brake indicator ?
pressure of the Yellow HYD when alternate braking activated or on ground with park brake
At what speed is the landing gear safety lock active ?
Speed above 260kt, landing gear cannot be operated
Do we have to manually set alternate brakes
No, they will self down-reg with failures
Describe Normal brakes
Operative when G Hyd available and A/SKID and N/W STRG on
Antiskid operative and Autobrake available
Braking and antiskid via BSCU
Describe Alt braking without ( antiskid
Antiskid deactivated either:
*Electrically (A/SKID and N/W STRG off, elec supply failed or BSCU failure) or
*Hydraucially (G+Y failure)
Brakes on accumulator only, auto limit to 1000psi (7 full brake applications)
Do we need inspection after shear pin failure
No if push stopped immediately
Yes if tractor touched towbar or if not stopped immediately
Max brake temp imbalance?
Temp diff between 2 brakes on 1 gear >150 deg with one >600 deg or <60 deg
Ave diff between L and R >200 deg or one brake >900 deg
When is autobrake available on TO
> 72kt (if spoilers armed they will immediately deploy when TL set to idle)
