Upgraded feature request - glide ring

airguy

Active Member
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Nov 10, 2008
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780
Location
Gods Country - west Texas
I would really like to see the glide ring take terrain into account (like Foreflight) rather than just draw a circular glide distance down in heavy terrain. We don't know if that ring is using the highest point, lowest point, average height, or something else to calculate how far out the ring goes, but it's obvious that terrain is not considered.

As a pilot that has actually needed and used that glide ring for real in the heat of battle once, that has my attention.
 

jnmeade

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Joined
Oct 9, 2011
Messages
262
Location
Eastern Iowa
Interesting idea. Would you want obstacles (like towers or tall buildings on hills or high tension lines) included? I'm thinking of use at night or in limited visibility. Hah! I'd have cleared that ridge if the cursed Great Wall of Chine had not been in the way. :)

Would one have to have a current or up-to-date terrain map for this to work or should it accept any terrain map?
 

RV8JD

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Joined
Dec 17, 2017
Messages
210
Location
WA State
+1

ForeFlight takes into account terrain, where Dynon does not. Some examples for SkyView and ForeFlight:

SkyView example. Green glide ring is circular and does not take into account the terrain. (It is offset for the calculated winds at the aircraft's altitude.)

i-z4CWQLB-L.png


ForeFlight example. Notice the jagged green glide ring taking into account the terrain. (It is offset for the forecast winds at the aircraft's altitude (either Packed before flight, or updated in-flight via ADS-B IN)).

i-FFJQdkn-XL.png
 
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airguy

Active Member
Joined
Nov 10, 2008
Messages
780
Location
Gods Country - west Texas
Interesting idea. Would you want obstacles (like towers or tall buildings on hills or high tension lines) included? I'm thinking of use at night or in limited visibility. Hah! I'd have cleared that ridge if the cursed Great Wall of Chine had not been in the way. :)

Would one have to have a current or up-to-date terrain map for this to work or should it accept any terrain map?
Certainly you would need the current terrain map - though those don't change often, now do they?

Obstacles - no. There are always obstacles - the purpose here is engine-out off airport landing opportunities. By the time you get down low enough to worry about the obstacles, you should already have them in sight and be maneuvering for your chosen landing spot. You can't solve all problems.
 

d3mac123

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Joined
Oct 6, 2020
Messages
31
I would love to see that too. Not only Foreflight but Garmin G3x/Pilot and some other apps have that.
 

cbennet12

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Joined
Mar 21, 2011
Messages
127
I brought this up with DYNON during their SnF live stream and they were receptive to this as a future upgrade. Obviously that is not a commitment nor does it tell us when it might be available. But it’s better than a no response. :)
 

RandomSquawk

New Member
Joined
Jul 17, 2020
Messages
20
This is huge. All the data is there already, and--as shown above--even EFBs are doing this. Where I live I have to constantly question whether the ring is predicting a realistic story, a falsely dismal end, or a fantasy.
 

maartenversteeg

I love flying!
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Oct 26, 2011
Messages
130
Especially when you have valleys as shown in the example above, the wind at altitude is a very bad preductor of the wind in the vallys, so the glide ring may suggest that there are options that really don't exist. Doing a true prediction of the options within glide range would require much more input. I think a glide ring with an appropriate wind offset over flat country woudl be a much better indication of the options
 

oxothnk

New Member
Joined
Apr 27, 2022
Messages
2
Location
Bay Area, CA and Phoenix, AZ
Just adding a +1 to request for terrain-aware glide ring. Not looking for perfect accuracy here, but even a rough approximation would be helpful. At a glance you could see the direction of lower terrain and safety; and helpful to know if you're able to clear a ridge (obviously depends on many factors, but you could set a conservative glideslope). I would actually argue the current glide ring is a *worse* implementation, as it suggests some rather impossible outcomes presently! Even a coarse terrain-aware version would alert you (via jagged edges) that you have some fluctuating ground elevation to consider.

I admit I'm a little sad when our fancy SkyView system can't do what mobile & tablet apps can do :)

Thanks for considering it, Dynon team! :)
James.
 
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