Final glide

I use an arrival height reserve. When flying to a destination airfield I readily and easily make mental adjustments up and down from it depending on conditions and distance to go. For me the benefit of setting the arrival height reserve is that if I see a green blob on my moving map when I am away from base I know that I have a fighting chance of reaching an alternate airfield. If you use a zero reserve then a green blob on the moving map is meaningless and you have to read the arrival height beside it.

By the way, at startup (after the gps has acquired) I check to see that the arrival height at the airfield I am sitting on is approximately minus my arrival height reserve. If the OP does this it might help him diagnose his problem. OP, please do report back to us on any further findings.

On Tuesday, September 24, 2019 at 7:29:21 AM UTC-7, waremark wrote:
I use an arrival height reserve. When flying to a destination airfield I readily and easily make mental adjustments up and down from it depending on conditions and distance to go. For me the benefit of setting the arrival height reserve is that if I see a green blob on my moving map when I am away from base I know that I have a fighting chance of reaching an alternate airfield. If you use a zero reserve then a green blob on the moving map is meaningless and you have to read the arrival height beside it.

By the way, at startup (after the gps has acquired) I check to see that the arrival height at the airfield I am sitting on is approximately minus my arrival height reserve. If the OP does this it might help him diagnose his problem. OP, please do report back to us on any further findings.

Ditto..

On Tuesday, September 24, 2019 at 10:29:21 AM UTC-4, waremark wrote:
OP, please do report back to us on any further findings.

As mentioned before, CNv uses TE altitude for final glide purposes. The normal circumstance with correct setup and database is that it will show about -200 feet arrival with the glider at rest, on the ground, very close to the selected waypoint. So in the OP's case, with 1000' reserve altitude, it should indicate about -1200.

T8

I do agree about the desire to have a "reserve" for graphical purposes. I believe clear nav can show the landing amobia both with and without reserve.. I wish the Lx would do this as well. I could cheat this in XCSoar with a terrain clearance. So the marginally reachable did not appear to be reachable with a 1000ft terrain clearance. But the best solution is a reserve that is only applied to the map view. This becomes a quick visual filter, only show me landing spots where I have the altitude for a decent approach. For me, the advantage of having an accurate arrival height is better than the inconvenience of checking if a candidate field has the margin I want. You only really get that after you have pick to go there anyway.

Rick

On Tuesday, September 24, 2019 at 11:41:33 AM UTC-4, RR wrote:
I do agree about the desire to have a "reserve" for graphical purposes. I believe clear nav can show the landing amobia both with and without reserve. I wish the Lx would do this as well. I could cheat this in XCSoar with a terrain clearance. So the marginally reachable did not appear to be reachable with a 1000ft terrain clearance. But the best solution is a reserve that is only applied to the map view. This becomes a quick visual filter, only show me landing spots where I have the altitude for a decent approach. For me, the advantage of having an accurate arrival height is better than the inconvenience of checking if a candidate field has the margin I want.. You only really get that after you have pick to go there anyway.

Rick

In Tophat the moving map shows the arrival altitude next to each landable waypoint that is within glide range. I use that instead of the color to identify the ones within range. (No colors on the Nook anyway :-)
And since, like Evan, I set the reserve altitude to zero, I do see some arrival altitudes on the map that are really too low to be safe, e.g., 300 feet. That's still good for planning, though, since it tells me that if I were to get a little higher, or closer, that landing spot will become a safer bet.