A 320 question
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A 320 question
A320 question: Is the ground spoiler inhibitor circuit keyed to wheel spin, and, is there a manual reversion mode if ice or other conditions keep wheel spin below the threshold? Is there no role for the squat switch?
Join Date: May 2006
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Hi!
If I read my FCOM right you get also get spoiler spoiler extension if RA is less than 6 feet and both MLG are compressed.
Partial spoiler extension if at least one thrust lever in reverse with the other at idle and one MLG compressed.
BR
Buster
If I read my FCOM right you get also get spoiler spoiler extension if RA is less than 6 feet and both MLG are compressed.
Partial spoiler extension if at least one thrust lever in reverse with the other at idle and one MLG compressed.
BR
Buster
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No, it's not. Busterpilot's answer is correct but incomplete.
Wheel speed is one of the logic conditions for GND SPLRS extension.
Inhibition is also keyed to wheel speed: you have inhibition between lift off and return of wheel speed below 23 kts or touchdown.
(touchdown condition= wheel speed>72 kts OR both MLG compressed and RA<6ft).
Proximity Detectors on Shock absorbers (I guess what you referred as "squat switch") will deliver the compression condition to the LGCIUs, so they have an important role.
(Ref: FCOM 1.27.10 p 12/13 and AMM 27.90.00 p26).
That said, Airbus recently modified the ground spoiler logic (new SEC standard 120 to cope with inappropriate TL position during flare...), but as far as I remember the wheel speed logic remained unchanged.
Wheel speed is one of the logic conditions for GND SPLRS extension.
Inhibition is also keyed to wheel speed: you have inhibition between lift off and return of wheel speed below 23 kts or touchdown.
(touchdown condition= wheel speed>72 kts OR both MLG compressed and RA<6ft).
Proximity Detectors on Shock absorbers (I guess what you referred as "squat switch") will deliver the compression condition to the LGCIUs, so they have an important role.
(Ref: FCOM 1.27.10 p 12/13 and AMM 27.90.00 p26).
That said, Airbus recently modified the ground spoiler logic (new SEC standard 120 to cope with inappropriate TL position during flare...), but as far as I remember the wheel speed logic remained unchanged.
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FCOM 1.27.10 p13 - shows an OR gate
Wheel speed above 72 kts
OR
MLG compressed.
Manual reversion: not for ground spoilers, but speedbrakes work if NOT in CONF FULL.
It's all in the books....
Wheel speed above 72 kts
OR
MLG compressed.
Manual reversion: not for ground spoilers, but speedbrakes work if NOT in CONF FULL.
It's all in the books....
