Discrepancies between audio warnings and SkyDemon displayed separations.

[grahambaker]

Using the latest versions of both PAW and SD, I'm observing huge differences in reported height separations for bearingless targets between PAW audio warnings and what is depicted on SkyDemon.

Typically, as a made up example, Sally Traffic will say 'warning, traffic 1100ft below' whereas SkyDemon will show it as -4.6. Empirically, from correlating warnings with known traffic on the ground when in the circuit, it would seem that that the audio warning is correct, but somehow it's getting corrupted on its way to the SkyDemon display.

Anyone else seen this?

[Admin]

Hi Graham

I thought I observed this on the rings actually using the latest SD rings but was not sure
I asked Tim who thought it may have been due to rounding errors converting metres to feet

But I am pretty sure EasyVFR is agreeing with the audio messages

Thx
Lee

[grahambaker]

Hi Lee,

I'm seeing it on the 'now highlighted in yellow' label that sits on the periphery of the SD ring.

[grahambaker]

I thought I observed this on the rings actually using the latest SD rings but was not sure
I asked Tim who thought it may have been due to rounding errors converting metres to feet

So are you saying that the problem lies entirely at the SD end? If so I will post a message on the SD forum.

[Admin]

SD and PilotAware made changes in this area in the last release, so the problem could be in either.
I am in contact with Tim Dawson, and together we will resolve this issue

Thx
Lee

[grahambaker]

Great stuff.

[Deker]

I seen / heard the same today.

At 3,600ft, audio alerts were giving traffic at 1000ft below, but mode S ring was showing the traffic at -3,600ft.
The other AC appeared to be 'following' us and as per audio alerts climbing to within 300ft our alt.
Heads spinning and eyes on stalks, couldn't see the other ac for about 8 mins, starting to think sally was telling fibs / wierd bug, but she was being persistent.
THEN, out of the right window, below and behind, there it was, and crossed underneath us.
The FlowerPlarm  we also carry was late in giving the warning.

I have various screen grabs of SD nav page, SD track log, PAW traffic page and FR 24 flight path of the other AC. (Post these once collated).
FR24 track explains whey we kept getting the alerts for so long a period.
PAW was worth every penny today.
Interesting to note, our mode c transponder doesn't show as SELF in the traffic page. Checked several times today.

Deker

[grahambaker]

Tim distributed a new iOS beta of SkyDemon for testing this morning. As it happens, I had a few flights planned today so I ran the new beta alongside the current public release on two separate iPads.

Looks like the problem is solved in the new beta - height separations reported in SD appeared consistent with the PAW audio alerts, so it won't be long before it makes its way into a new release.

Well done chaps!

[exfirepro]

Hi Graham,

Tim actually gave us access to the new code last Wednesday. Unfortunately as PC/ Android only, so I downloaded it onto a Nexus 7 in the early hours of Thursday morning, ran it (satisfactorily) from East Fortune to Sywell on Thursday and reported back positively to Tim on Friday morning at the Rally. After some discussion, he also did some other changes to remove persistence, which was causing multiple 'bearingless target' rings to remain visible at the same time and to improve the visibility of the relative altitude on the 'bearingless target' rings, which should also be in the new beta - I haven't had time to download / test it yet.

I must say I was really pleased at how helpful Tim was to PilotAware over the weekend. Thanks Tim you are a gentleman.

Regards

Peter