Why Low altitude alert

[BGSM]

I was issued a low altitude alert by ATC on a visual approach which is not a good thing.

I was on the base to final when it was issued and less than a mile from the runway. When I rolled out on final I was above the glidepath.

I never had that issued to me before, ATC has a tendancy to slam dunk me a lot and i fly the same thing almost every day. Will a fast desent rate cause the alarm ? Is ATC required to issue it? I was just surprised because I was above the glide path on final and fly the same thing almost everyday and never had it issued.

 

[Donsa320]

I was issued a low altitude alert by ATC on a visual approach which is not a good thing.

I was on the base to final when it was issued and less than a mile from the runway. When I rolled out on final I was above the glidepath.

I never had that issued to me before, ATC has a tendancy to slam dunk me a lot and i fly the same thing almost every day. Will a fast desent rate cause the alarm ? Is ATC required to issue it? I was just surprised because I was above the glide path on final and fly the same thing almost everyday and never had it issued.

Yes, a high descent rate can trigger an alert. The software looks ahead a few seconds and certainly can alarm if it looks like you will lose obstacle clearance at your current descent rate. The radar sweeps are already history by the time the computer sees them And yes, the controller must alert you if he/she receives an alarm. You could be levelling off by the time that all happens. BTW it has nothing to do with the glide slope.

 

[Lrjtcaptain]

Yes, we get the LA alot on planes over the foothills near our airport. IF a LA alarms on the RADAR we are required to issue it. Usually triggerd by fast decents or close prox to terrain.