ForeFlight/Stratus AHRS feature reliable?

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TrueCourse

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TrueCourse
I've got a Stratus 2S and upgraded to ForeFlight's Pro Plus subscription to access the AHRS feature for the backup attitude indicator, but so far it's not very reliable. It seems like it works part of the time on most flights but eventually stops working. My last flight the AHRS feature worked for a good 20 minutes or so then it stopped working and has the "No Attitude Information" displayed. The rest of the mobile app works fine. The receiver is mounted in a cool spot on the side windshield. Latest firmware installed. Shouldn't be reception or antenna related. Anyone else have this issue?
 
Mine works great with the Appareo transponder and Stratus 3i. Never dies like that - sorry, no suggestions for what could be your issue.
 
Looking back an the Tracking Logs the pitch and bank seems to quit after about 45 to 60 minutes or so. So, while sitting here at home with the Stratus next to me I turned it on. The AHRS worked for awhile then stopped working. Hmm. I'll keep digging through the data to see if I find something that provides a clue.
 
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Is your display device shutting down the Bluetooth in an attempt to save battery power?
 
I have this setup in the Cessna and it has proved to be 100% reliable. What kind of symptoms have you had?
 
smv said:
Is your display device shutting down the Bluetooth in an attempt to save battery power?
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It doesn't use Bluetooth for any of this, but does use the Stratus WiFi signal. I believe I was getting ADS-B weather updates after this occured, so I don't believe it was dropping the WiFi connection. And ForeFlight was selected to use the Stratus GPS, not the iPad GPS, and it never stops creating a track log.

MBDiagMan said:
I have this setup in the Cessna and it has proved to be 100% reliable. What kind of symptoms have you had?
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I described it in the first post.

I contacted ForeFlight Support this afternoon and they asked for the diagnostic and data logs to see if they can figure it out. We'll see.
 
I'm not familiar with the Stratus and the way it implements the AHRS module, but maybe some part of the following may be of some use.

The AHRS module in a Stratux (homebrew ADSB-in device based on a Raspberry Pi, one or two SDR usb modules, and option GPS and/or AHRS usb modules running open source software) needs to be oriented AND calibrated correctly, and lots of folks have trouble because they assume that one of those steps takes care of the other. I realize I'm shooting completely in the dark, but are you absolutely certain you have followed whatever setup/calibration steps are necessary for your Stratus? A common complaint w/ the Stratux is that the AHRS will drift over a period of 20 minutes or so then become completely unusable, and usually that means that someone may have followed the orientation procedure but not the calibration.

If that's not helpful, my apologies. Just guessing.
 
TrueCourse said:
It doesn't use Bluetooth for any of this, but does use the Stratus WiFi signal.
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Thanks! That was close. Almost made it to the end of the day without learning something new! ;)
 
Mine has been reliable, but I’ve heard from a person or two that have had the same problem you do @TrueCourse
I seem to recall at least one of them saying it was a faulty unit, which stratus replaced after some talk with their tech department.
 
My Stratus is a permanently mounted one that came with the Appareo. I think it is a 3i model. It is mounted and set up with plane level. I don’t think a portable Stratus thrown on the panel will be reliable. Can you mount it permanently with the correct orientation? When you lose the signal do you check FF in More... Devices to ensure it is still connected?
 
I have my 2S on the floor under the back of the pilots seat with hard-power and external antennas mounted to the inside of back side windows. The AHRS feature is rock solid and I believe I could use it to get down in an emergency.
 
Pray that you will never need it in an emergency, but yes, it would probably be a great help.

Back in a August,I left San Marcos headed to MountPleasant. About a 260 nm flight. About 35 nm into it I got over solid overcast until about 35 nm from my destination where it cleared again. About halfway over the top I lost all vacuum. I watched the Foreflight synthetic vision closely and hoped I wouldn’t have to go down for any reason. Thank God I didn’t have to, but the AHRS and synth vision would have been significantly better than nothing if I would have needed it.
 
MBDiagMan said:
Back in a August,I left San Marcos headed to MountPleasant. About a 260 nm flight. About 35 nm into it I got over solid overcast until about 35 nm from my destination where it cleared again. About halfway over the top I lost all vacuum. I watched the Foreflight synthetic vision closely and hoped I wouldn’t have to go down for any reason. Thank God I didn’t have to, but the AHRS and synth vision would have been significantly better than nothing if I would have needed it.
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I flew a practice approach last month using it with sim failed AI and BDHI in the 182 and it was much harder than I thought. A significant amount of lag. I think if I were in this last ditch area (which is a whole lot better than partial panel) I'd still fess up to approach so hopefully nice smooth vectors to final. I'd certainly encourage everyone to give it a try before you hopefully never need it.
 
MBDiagMan said:
I don’t think a portable Stratus thrown on the panel will be reliable. Can you mount it permanently with the correct orientation? When you lose the signal do you check FF in More... Devices to ensure it is still connected?
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The correct orientation was being used. When I noticed it failed I was invariably busy with other things (no autopilot) and didn't take the time to check all the settings. When it failed the other day it was still connected.

QUOTE="GaryV, post: 2858346, member: 29690"]I have my 2S on the floor under the back of the pilots seat with hard-power and external antennas mounted to the inside of back side windows. The AHRS feature is rock solid and I believe I could use it to get down in an emergency.[/QUOTE]

Although I have limited experience with it, I'd have to agree that this sounds like a good setup. Limiting the vibration from less sturdy mounting.

Pugs said:
I flew a practice approach last month using it with sim failed AI and BDHI in the 182 and it was much harder than I thought. A significant amount of lag. I think if I were in this last ditch area (which is a whole lot better than partial panel) I'd still fess up to approach so hopefully nice smooth vectors to final. I'd certainly encourage everyone to give it a try before you hopefully never need it.
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I'm thinking if its enough to help the pilot keep the right side up and allow for some basic maneuvering, I'd be happy. In other words, treat it like a fancy partial panel.
 
After the logs were sent to ForeFlight, I did some more reading and found a thread that essentially explains what is probably going on. When the WiFi link for the Stratus was created it was setup using the WPA2 protocol with a password. It's an option provided under Devices. Works fine, until it doesn't. So, I'm testing it now to confirm the suspicions that, for whatever reason, after nearly hour (plus or minus X minutes) it decides its had enough and the AHRS stops working. Wish I had found this earlier. Why use WPA2 when setting it up? Because a few years ago when I started using FF I didn't want the guy I was flying formation with to have access to my signal. Just kidding. It's a simple habit these days to use security when its available and I never thought, with it working OK for so long before dying, that I would need to recreate the WiFi connection. Lesson learned - if this is the actual problem.
 
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My Foreflight Sentry had an issue with AHRS working, turned out, I had to do a factory reset, then upgrade the firmware. It works pretty good now. I'd hate to try and fly hard IFR with it. But, its better than nothing.
 
Does anyone know if there are any actual events where the AHRS on a Stratus (or similar unit) actually saved the day in solid IFR after a vacuum failure?
 
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