SkyDemon Forums

Altitude deviation alarm / alert

http://forums.skydemon.aero/Topic38934.aspx

By James Pearce - 5/9/2026 9:00:33 AM

Is there a way to set an alarm in SkyDemon for a predetermined altitude? Situation - I fly between 2 areas of controlled airspace with lower limits of 2000'. I usually maintain a 400' - 500' buffer but had a bit of a squeak yesterday in thermic conditions and lack of attention that got me to within 120' - Phew  😳. An alarm at 1700' could alert me well before I get close to the airspace. It's all down to me, I know but it is a feature I would use. Thanks, James.
By GalaxyzA11+ - 6/9/2026 5:20:05 AM

TimT - 6/7/2026 9:40:46 AM
TimT - 5/10/2026 12:38:52 PM
I can set an ATL Alert on my Garmin TXP. But that would be pressure ALT. In our neck of the woods, PA is always a bit lower than actual ALT, so that gives me that 100 or 200 ft buffer.

Let me clarify how this ALT Alert on Garmin Transponders actually works. I hadn’t used it of a while, so I misrepresented it in my above post. As you will see, this eliminates the issue of Pressure ALT vs QNH-based ALT:

The feature on my Garmin Transponder is called “ALT MONITOR”. It assumes that I turn it (the ALT MONITOR) ON when at the correct ALT. Thereafter it displays my deviation from the set altitude (e.g., “-90ft”) and further shows/sounds a “LEAVING ALTITUDE” alert if the deviation is greater than the deviation limit (default is 250 ft., but this can be changes during configuration).

So the OP James could use this feature the following way:

-    Assume controlled airspace above from 2000 ft ALT
-    James wishes to fly at 1500 ft ALT to maintain a safe buffer
-    Once established at 1500 ft ALT, turn on the ALT MONITOR
-    In case James inadvertently climbs above 1750 ft AGL, a LEAVING ALTITUDE alert will sound


Hi,
Ok this will do it for some pilot who want to set it mannually ... And then will probably forget to set it later ?
As you said first, the alert function "airspace above" does already exist in SD.
The user has to enable it in the settings.
It will provide several alarms, each time you climb again you will get a new alarm trigger.
You get a popup on the screen, and a vocal message over headset if you have bluetooth and chose vocal alert in addition of the popup alert.
It is automatic, btw you don't need to set it mannually for each level.
HTH.