iFly GPS Forum

Hey FlyingMonkey just a heads up, I have been a member on a few aviation forums with the user name "Flying_Monkey" for several years and have a Youtube channel called "SoCal Flying Monkey."  Some people here thought that your post was from me and I just want to clarify that we are not the same person. Sorry for the interuption in the thread.  

-Eric

INSTAGRAM: http://instagram.com/socalflyingmonkey

YOUTUBE: http://youtube.com/socalflyingmonkey

Green Light, check:

Status, check:

Traffic Layer, check:

Other settings:

So, a few other anomalies I noticed on yesterday's flight:

At one point I had two relevant targets, one ~6 miles behind me in a cross track 900ft below my altitude, the other directly ahead ~5 miles 200ft below my altitude.  The 740b chose to alert me (with an audio ping and text popup box) to the traffic behind which was no factor, and ignored the one dead ahead.  As you see in the following pic, there is an alert for the target behind, and the "next" button is greyed out, indicating no other alerts...

Maybe the iFly deternined that since the traffic was going the same direction with slow/no/negative closure, it was not worth an alert.  However, shortly after that the traffic made a 90° turn to a crossing track.  Still no alert, as you can see the only new alert is the approaching Class B warning (the second alert in the box was the same airplane that was behind me):

After that, the target continued its turn until it was essentially head-on to my airplane.  I spotted him well out and waited for the ADS-B alert from the 740b to see when it would happen.  Here was the first text box popup and audio alert:

So the first alert of any kind (icon, text, or audio) occurs at co-altitude, 1.9nm range, nearly head-on at high closure.  If it can be explained that this is expected behavior when everything seems to be working properly and my thresholds are set to 7nm/5000ft, I'd be interested to hear that explanation.  You can see from the ETE box that this is a target that was visible to the system for at least 3-4min (it was actually about ten minutes, but I don't have pics to support that so we'll go with what I can show), yet despite large thresholds the system chose not to alert until the target was very close. 

Before anybody jumps on me for snapping pics with a target that close...as I said I had spotted the target visually far before this, and I was actually in a slight left bank away from the target when I snapped this, after determining it was safe to do so.

Potential explanations or remedies welcomed on this.

Thanks for the response Mike.

There is nothing wrong with Flight Following.  I choose rarely to use it except on long cross country flights, but it's a good tool.  Keep in mind, though...one of the points used to sell ADS-B to pilots is that, when equipped with ADS-B in and out, the traffic picture you see should be literally the same as what an ATC operator sees.  So while it is always nice to have an extra set of eyes, at least in theory you are not supposed to gain any additional visibility to traffic over what ATC sees.  And of course FF doesn't address the obstacle alert issue that I have mentioned and find to be a concern.

My only point in this thread is that, if I were getting the expected alerts at the expected ranges, and seeing targets that seem obviously missing (e.g. flying along beside another airplane and he can see me but I can't see him on ADS-B, in spite of both systems reporting receiving ADS-B traffic), I'd be a happy camper.  But I'm simply not convinced that the alerts & obstacle/traffic visibility are working as intended, and if they are then I feel I need a detailed explanation of how they are triggered and presented so that can adjust my settings and/or expectations.

I will report good news when I have it too, I'm not just a "Debbie Downer".    Today I flew a 1.5hr flight with another airplane, with both my Stratux/iFly combo and a borrowed Garmin GDL-50 using Garmin Pilot.  The entire flight both systems showed virtually identical traffic and I seemed to be getting appropriate alerts from both.  So any isses with the iFly alerts or traffic visibility, if they in fact exist, are apparently intermittent.  I will continue testing for a week or two with both systems side-by-side and will report any discrepencies or lack thereof.

Also in the plus side for iFly:  Garmin traffic alerts are either "on" or "off", there is no configurability.  Alerts are triggered when the system detects a potential traffic conflict within 30 seconds.  That seems pretty tight to me -- I do prefer being able to set thresholds for alerts and iFly does have that feature.  The only good thing you could say about the Garmin system is that if you get an audio alert, it's a real issue and not just an advisory, and reduces cockpit noise and distractions...almost like a TCAS alert requiring immediate action.