iFly GPS Forum

I would see the glide circle as something that comes up when you hit the NRST tab at the bottom of the screen, and then the red emergency triangle button in the upper right of the box that pops up.  Or maybe it would be an option you set to say you want it on all the time (which I might) or only when you hit the emergency triangle button.

Right now, when you define an aircraft to iFly, you specify what the glide ratio is.  So knowing that and your altitude, the software can easily calculate your theoretical glide distance. 

That's what it does when you hit NRST and then the red triangle.  It colors the nearest airports red, yellow, or green based on whether you can glide there (theoretically).  That's why I find it frustrating that they won't provide a simple optional theoretical glide ring around the aircraft.  They're already providing a theoretical glide indicator in that box now.  Yeah, if you want to be perfect you'd take into account terrain and winds aloft, blah blah, but I'm pretty sure they're not doing that now when they color the airports.  So, what's the diff?

Hook

There is a nav app that does give a glide circle. This circle is not concentric because it does account for terrain and winds. I question the accuracy since knowing the winds at various altitudes is a hard call.

On my Dynon D10 I can see wind direction and speeds and as I descend both the wind speed and direction change..

I can remember the free Nav app I used...maybe Avare or Naviator..that gave glide ratio. It was pretty good as I recall and I used to experiment with it by trying different glide speeds at idle.

John M

I agree with you EMike.  Just underestimate the size of the circle and call it good.  It's just theoretical, just a visual on the map to aid in making a decision under pressure.  They already WAY underestimate in their red/yellow/green coloring of the airports you get with NRST (which I pointed out over a year ago based on testing).  Come to think of it, their underestimation probably was around 20%.

This also goes back to my complaint about the blackness of the development pipeline.  Is anyone at AP considering doing this glide circle?  Who knows?  We make suggestions and don't know if they're being considered or discarded.  Is there some hidden criteria a suggestion has to meet?  For this particular suggestion, is liability an issue?  I suggested a first-use-of-feature popup window where the user would have to acknowledge that the glide circle is only an estimate and may be incorrect due to several factors.