A220 LANDING GEAR & BRAKES Questions with Detailed Verified Answers

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A220 LANDING GEAR & BRAKES Questions
with Detailed Verified Answers

Question: What are the computers that control the landing gear and
brakes?

Ans✅ ✅: 2 LGSCUs (Landing Gear & Steering Control Units) and 2 BDCUs (Brake
Data Concentrator Units)

[LGSCU inhibits gear retraction on the ground; monitors and evaluates the door
proximity sensor

logic displayed on the DOOR synoptic]

Question: Which hydraulic system provides pressure for extension and
retraction of the landing gear?

Ans✅ ✅: HYD 1 [Extension: 250 kts / Extended 250 kts / Retraction: 220 kts]

Question: How is alternate gear extension powered?

Ans✅ ✅: DC ESS 3

Question: When will the ALTN GEAR DN EICAS advisory message
display without using the alternate gear switch?

Ans✅ ✅: After every 550 flight hours, the LGSCU does an alternate gear extension
to test the alternate

extension circuitry for abnormal conditions (dormancy check); advisory displays during
test until

gear is down

Question: Below 30 kts, how many degrees is the tiller capable of
turning the nose gear?