A 320 question
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Joined: Nov 2000
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From: UK
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?
Joined: May 2006
Posts: 11
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From: Europe
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
Joined: Dec 2004
Posts: 291
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From: Between Vedex and Murag!
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.
Joined: May 2000
Posts: 1,021
Likes: 2
From: Glorious West Sussex
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....
