AMI indicator...
04-09-2008 | 07:28 PM
#1
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From: CRJ
AMI indicator...
ok, so for this thing i am working on i have to explain what the ami indicator is and what it is used for. here is my best and quickest explanation.
The AMI (alpha margin indicator) is a function of the windshear alert and warning system. Its literal indication is the angle of attack that will activate the stick shaker indicating an approaching stall condition. In the CRJ during a decreasing performance windshear we fly the flight director for escape guidance until ground contact is imminent, then the thrust levers are firewalled and the AMI is followed to allow the plane to maintain the maximum allowed angle of attack without stalling the plane.
so does that sound like a good explanation? anyone have any other info on the ami.
The AMI (alpha margin indicator) is a function of the windshear alert and warning system. Its literal indication is the angle of attack that will activate the stick shaker indicating an approaching stall condition. In the CRJ during a decreasing performance windshear we fly the flight director for escape guidance until ground contact is imminent, then the thrust levers are firewalled and the AMI is followed to allow the plane to maintain the maximum allowed angle of attack without stalling the plane.
so does that sound like a good explanation? anyone have any other info on the ami.
04-09-2008 | 07:42 PM
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Am I Wrong??????????
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From: ThE jEtTtTtTtT
Thats about all there is to say....Our company says at the sight of a red WINDSHEAR warning.....we firewall the thrust and pitch for the AMI
A good technique that I use is to initially pitch for the AMI or just a hair under. Once you are out of the downdraft, you can transition to the Flight Director pitch attitude.
Remember too....if the shaker is confusing you....you can always disable it by pushing and holding the A/P Disc button on the yoke...but be really careful doing that, you could end up stalling and having no idea why, focusing soo much on pitch and forgetting about airspeed
A good technique that I use is to initially pitch for the AMI or just a hair under. Once you are out of the downdraft, you can transition to the Flight Director pitch attitude.
Remember too....if the shaker is confusing you....you can always disable it by pushing and holding the A/P Disc button on the yoke...but be really careful doing that, you could end up stalling and having no idea why, focusing soo much on pitch and forgetting about airspeed
04-09-2008 | 07:47 PM
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From: CRJ
i figured there would be some discrepancies on how it is used.
at pinnacle in a decreasing performance windshear you call max thrust (n1 just out of the red) spoilers in. make no configuration changes and fly the flight director because it is giving ws escape guidance. if the plane continues descending then the thrust levers are firewalled and we pitch for the ami as a last ditch effort.
at pinnacle in a decreasing performance windshear you call max thrust (n1 just out of the red) spoilers in. make no configuration changes and fly the flight director because it is giving ws escape guidance. if the plane continues descending then the thrust levers are firewalled and we pitch for the ami as a last ditch effort.
04-09-2008 | 11:21 PM
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AMI stays up 60 seconds, regardless of whether the W/S warning stops, right?
That's interesting some operators go for the AMI instead of the FD on dec. performance shears.
Airsupport, I might have to take some lessons from you on PBS sometime. From some of your other posts, it sounds like you are a PBS god.
That's interesting some operators go for the AMI instead of the FD on dec. performance shears.
Airsupport, I might have to take some lessons from you on PBS sometime. From some of your other posts, it sounds like you are a PBS god.
04-10-2008 | 05:05 AM
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From: CRJ
04-10-2008 | 07:59 AM
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From: Engines Turn or People Swim
At both airlines I worked for we pitch for the FD first. If that didn't arrest the descent, then you go for the AMI. If that's not enough, you can pitch as much as needed up to intermittent stick shaker.
04-13-2008 | 10:04 AM
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From: retired
