Protections and Stabilities 1 Flashcards
What are the indications that alpha lock is triggered?
A-LOCK pulses on EWD (just above the slats on the slat/flap position indicator)
What are the characteristics of abnormal attitude law?
Operates like normal law with no stabilities, and auto pitch trim is also lost
What does low speed stability do in alternate law? Can this be overridden?
Introduces a progressive nose down input, which can be overridden by pilot input
In mechanical backup, what can be used to control the aircraft?
THS, rudder and differential thrust
What does high speed stability do in alternate law? Can this be overridden?
Introduces a nose up demand when above VMO/MMO which can be overridden by pilot input
When do you get an overspeed warning?
VMO +4
MMO +0.006
At what point does AP disconnect in slow speed?
Valpha prot + 1 degree
At what angle of bank does the AP disconnect?
45 degrees
When is abnormal attitude law triggered?
When normal law envelope is exceeded by external forces (eg wake turbulence encounter)
What happens once recovered from abnormal attitude law?
Auto pitch trim is regained, and aircraft will be in alternate law for the remainder of the flight. The aircraft lands in alternate law
With sustained sidestick input, what will speed decay until?
ValphaMax
At what angle of bank do the FDs disappear?
45 degrees
When does AP disconnect in overspeed?
VMO +15
MMO +0.04
What is the purpose of abnormal attitude law?
Prevents normal law from impeding recovery
With A/THR engaged, what lowest speed will you decrease towards?
VLS +/-2kt
When does the aircraft revert to direct law?
When in alternate law, gear down, AP off for landing
What is the high AoA protection bank angle limit?
45 degrees
What triggers alpha lock?
Activated by SFCCs when flap lever moved from position 1 to 0 and either:
Alpha above 8.5 degrees or
Speed below 148kts
How can you identify that you are in mechanical backup?
MAN PITCH TRIM ONLY in red on PFD
What is VLS?
Lowest selectable speed
What is VMO/MMO?
350kt/M0.82
Below alpha prot, what does sidestick command?
Alpha, instead of load factor
Do we keep protections and stabilities in direct law?
No, but overspeed and stall warnings still remain available
How can you tell you are in direct law?
USE MAN PITCH TRIM in amber on the PFD
Will AP disconnect in alternate law for high speed or bank?
Yes for both. Speed if above VMO/MMO, bank if above 45 degrees
What are the main protections in normal law?
Load factor
Pitch attitude
Bank angle
High speed
High AoA
What are the load factor limitations in normal law?
Clean -1g to +2.5g
Configured 0g to +2g
What does the low speed regime in normal law provide?
Low energy aural alert “SPEED”
Alpha floor protection
Neither of these are flight control protections
What replaces the low speed alpha indications?
VSW
What is the maximum bank angle for auto pitch trim and bank hold?
33 degrees
