iFly GPS Forum

was flying over northern Kentucky today at 5500 ft, chart showing highest obstacle in the 2,000 ft range, and got 2 terrain warnings to pull up.

thought I would pass along as it is first I have had. did note that the machine did seem to have issues as to which chart to display a bit earlier.

I've had a couple of terrain warnings go off at altitude recently too (since upgrading to 720). However, I noticed that the GPS altitude displayed was incorrect at that point too (fixed its self shortly thereafter).

So I think at least in my case that it may not have been an iFly software logic issue but rather the GPS engine (reporting wrong altitiude to the software for a moment) that caused this for me (explains insane VST also).

Is it possible as I've experienced, you had a weak GPS signal too, possibly giving a bogus gps altitiude that the software was simply reacting to? Or was your GPS altitide indicating correctly (pointing to software logic issue)?

- Alasdair

Yes it is possible that I had a weak GPS signal. I was not using the remote antenna at the time, and I normally have it. However, when I thought about that, and looked at the display it had the correct altitude ( do not recall as to some wild climb/decent rate). But, I cannot discount that possibly it had a temporary issue,... did not see a lost lock or whatever display either though.

It is disconcerting to see such when in general the display and warnings have been rock solid on earlier flights.