Garmin ESP Underspeed Protection "Airspeed" Voice Alert

[PT20J]

I tested this and there is no voice alert as described in he G3X Touch Pilot's Guide and GFC 500 AFMS although the pitch servo does provide an elevator down force. Garmin support confirmed with engineering that the alert does not exist. I requested that an enhancement request be logged to include the alert (as opposed to just correcting the documentation). Having the automation pitch the aircraft without an alert is poor human factors design, in my opinion. That's essentially what confused the ill-fated 737 MAX crews. 

Above 2000' where LVL mode is armed, if I held airspeed below 69 KIAS long enough, LVL would activate with voice annunciations "ENGAGING AUTOPILOT" and "AIRSPEED"

Skip

[PT20J]

Did another test this afternoon. The visual message described on page 7-1 of rev 5 of the M20J/M20K  AFMS: "When 69 KIAS is reached , a visual MINSPD message will appear above the airspeed tape ..." also does not happen.

Skip

[Ragsf15e]

Yeah that seems like it needs fixed.  Do you get voice and visual airspeed alerts with the AP engaged?
 

AP Engaged: The g1000 Meridian I fly makes both the voice and visual alerts you describe while pitching down to avoid stall.  It would definitely be a surprise without the warnings.  Actually, if the AP is engaged, the min airspeed caution comes on early, before the pitch down (say 10kts above) so that you have time to correct.

[PT20J]

2 hours ago, Ragsf15e said:

Yeah that seems like it needs fixed.  Do you get voice and visual airspeed alerts with the AP engaged?
 

AP Engaged: The g1000 Meridian I fly makes both the voice and visual alerts you describe while pitching down to avoid stall.  It would definitely be a surprise without the warnings.  Actually, if the AP is engaged, the min airspeed caution comes on early, before the pitch down (say 10kts above) so that you have time to correct.

Well, according to the manual the annunciation is only part of ESP which is only active when the autopilot is not engaged. But I didn't test it and have learned that the Garmin manuals aren't always a trusted source of information. 

[Ragsf15e]

54 minutes ago, PT20J said:

Well, according to the manual the annunciation is only part of ESP which is only active when the autopilot is not engaged. But I didn't test it and have learned that the Garmin manuals aren't always a trusted source of information. 

You should try it with ap engaged in altitude hold.  I bet you get both annunciations.  Now that I think of it, when you activate the roll esp by rolling outside the limits, you don’t get a caution or annunciation either, just nudges back toward level flight.  I bet they just put that text in the wrong section… i bet it’s supposed to show what the AP will do when engaged and in a low speed condition.

[PT20J]

On 2/2/2022 at 1:03 PM, Ragsf15e said:

You should try it with ap engaged in altitude hold.  I bet you get both annunciations.  Now that I think of it, when you activate the roll esp by rolling outside the limits, you don’t get a caution or annunciation either, just nudges back toward level flight.  I bet they just put that text in the wrong section… i bet it’s supposed to show what the AP will do when engaged and in a low speed condition.

I tried it today and you were right. When the autopilot is engaged and the speed goes below 69 KIAS, A MINSPD message appears above the airspeed tape and an audio annunciation AIRSPEED! is heard. This does not happen when ESP is active but the autopilot is not engaged unless you hold the airspeed below 69 long enough for ESP to activate the autopilot in LVL in which case you get the MINSPD and AIRSPEED! alerts.

Skip

[Ragsf15e]

15 minutes ago, PT20J said:

I tried it today and you were right. When the autopilot is engaged and the speed goes below 69 KIAS, A MINSPD message appears above the airspeed tape and an audio annunciation AIRSPEED! is heard. This does not happen when ESP is active but the autopilot is not engaged unless you hold the airspeed below 69 long enough for ESP to activate the autopilot in LVL in which case you get the MINSPD and AIRSPEED! alerts.

Skip

It’s really similar to the g1000 gfc700 in a lot of ways!  Glad you guys got a nice day to fly over there, this side of the state was nice too and we went for $100 hamburgers in idaho.  Bouncy fuel pressure and all.

[PT20J]

2 minutes ago, Ragsf15e said:

It’s really similar to the g1000 gfc700 in a lot of ways!  Glad you guys got a nice day to fly over there, this side of the state was nice too and we went for $100 hamburgers in idaho.  Bouncy fuel pressure and all.

I’m envious - the fog burned off too late for lunch, so I just burned gas in the local area testing stuff.