Backup AHRS suggestions

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Sundancer

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Our club plane has an Aspen AI/HSI, which I like pretty well. It doesn't require a backup AI for IFR, however, which I don't like quite as much.

I'm a FF user (and fan), so there are a lot of available portable devices that can provide AHRS data to FF. Looking for advice on real-world experience with a portable. Done some reading here and elsewhere and eliminated the Stratux. FF pushes their Sentry, of course. What I don't know - do any of them provide truly useful/reliable AHRS data to FF?

I'll also be using it for GPS input to FF - we have panel mount GPS sources, but I like having an independent device if the airplane's electrons go wonky.
 
Sentry you have to set the zero point. They are decent but I wouldn’t try them in IFR, personally. You still have your turn coordinator & altimeter.

Sentry has a CO detector which is nice, but check compatibility.
 
mandm said:
They are decent but I wouldn’t try them in IFR, personally. You still have your turn coordinator & altimeter.
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I agree with this. I tried to use the Sentry panel on my recent ICC. Found it very difficult to use. I did a lot better with my partial steam gauges.
 
Garmin GDL39-3D, -50, -52 all will suit your purpose. The -52 does all the GDL stuff plus adds XM weather. If I lived in the lower 48 that's what I'd have. All that said, I'm a Garmin Pilot guy. The only reason I commented is that I read that Foreflight and the GDLs are compatible. I have no PIREP for how they get along together.
 
I've tried both the Sentry and the Stratus...IMHO, the Stratus blows away the Sentry while flying on the AHRS...the Sentry lags, is jerky/twitchy. BUT...I don't depend on either as my second line of defense...I have a standby vacuum pump.
 
Country Flier said:
I've tried both the Sentry and the Stratus...IMHO, the Stratus blows away the Sentry while flying on the AHRS...the Sentry lags, is jerky/twitchy. BUT...I don't depend on either as my second line of defense...I have a standby vacuum pump.
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In my limited experience with the Sentry, I also found it to lag behind a half second of so then 'catch up' to the attitude indicator. I own a Stratus 3 and it tracks the AI lock step. The 182 I bought has a GTX-345 so I get b/u AHRS from it and keep the Stratus for a b/u of the b/u. The Stratus and the GTX345 are in sync with the vacuum AI. The Sentry was in another aircraft.
 
Sundancer said:
Our club plane has an Aspen AI/HSI, which I like pretty well. It doesn't require a backup AI for IFR, however, which I don't like quite as much.

I'm a FF user (and fan), so there are a lot of available portable devices that can provide AHRS data to FF. Looking for advice on real-world experience with a portable. Done some reading here and elsewhere and eliminated the Stratux. FF pushes their Sentry, of course. What I don't know - do any of them provide truly useful/reliable AHRS data to FF?

I'll also be using it for GPS input to FF - we have panel mount GPS sources, but I like having an independent device if the airplane's electrons go wonky.
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Since it is not your personal plane to add a panel AI, if you did not mind the expense, and there is an easy mount path, I would consider the Levil “BOM.”
It would give you everything you want and angle of attack indicator plus air data, and works even with total electric failure. It’s technically portable with the right mount, and is heated to avoid icing up!
 
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FORANE said:
Dynon D3
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A client of mine has now had two of these - neither one has worked right. It would bounce all around and usually not show the correct attitude anyway. I don't know the story of his calls back to Dynon, it's still on his panel but he never turns it on (and when I have, yeah it shows clearly erroneous information). His opinion of the product is not good.
 
I only have one but would buy another one. Mine has worked perfectly, even when the Garmin G5 in the same panel suffered attitude indicator failure in turbulence.

I like that it shows GPS derrived altitude as a quick cross check and backup for frozen static.
Also it doesn't require 2 year altimeter check as part of a pitot static altimeter routine.
 
Stewartb said:
Garmin GDL39-3D, -50, -52 all will suit your purpose. The -52 does all the GDL stuff plus adds XM weather. If I lived in the lower 48 that's what I'd have. All that said, I'm a Garmin Pilot guy. The only reason I commented is that I read that Foreflight and the GDLs are compatible. I have no PIREP for how they get along together.
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Thanks - it's looking like results vary a lot, probably based on "installation" particulars, including the GDL devices. I'm neutral on Garmin - I have a lot of time with their panel mounts which are fine, but the interfaces are klunky.

Yeah, FF/iPad are device neutral, and will accept data from just about any of the devices out there.

The BOM is interesting, but it's a shared airplane and I'd have to sell the BOM as a basically permanent add-on. I'm the new guy and want to tread lightly for now. Plus it's about $2K.

Based on the mixed reviews of all the devices I think I'll do the Sentry and hope the airplane, connectivity, software, mounting, etc. end up working together OK. If not I'll have a pricey GPS source for FF. Sentry is FF only, but that's OK - I've tried the other apps and FF is the clear winner for me.
 
If you can borrow a Sentry and a Stratus 3 and try before you buy I would highly suggest doing so. My Stratus3/Ipad air and mini 6 tracks with a G5 and AHRS from a GTX345 perfectly. I have flown with a friend using a Sentry / ipad mini and it was not stable enough to consider using for anything other than moving map/adsb in. I don't know if the issue is the ipad connected to the Sentry but as @Country Flier notes it is not an isolated occurrence.
 
Sundancer said:
The BOM is interesting, but it's a shared airplane and I'd have to sell the BOM as a basically permanent add-on. I'm the new guy and want to tread lightly for now. Plus it's about $2K.
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I don’t think you mentioned the aircraft, but if a C172 or another with struts, IIRC, there is a quick release clamp that would avoid the conversation with your shared mates. But yes, about 2K for all that it does.
 
Sentry arrived overnight from Sporty's. I'll test it tomorrow, weather permitting, and let you know how it goes. Works fine mounted to my fridge : ). Easy to connect to my iPad mini and FF.
 
robin ardoin said:
If you can borrow a Sentry and a Stratus 3 and try before you buy I would highly suggest doing so. My Stratus3/Ipad air and mini 6 tracks with a G5 and AHRS from a GTX345 perfectly. I have flown with a friend using a Sentry / ipad mini and it was not stable enough to consider using for anything other than moving map/adsb in. I don't know if the issue is the ipad connected to the Sentry but as @Country Flier notes it is not an isolated occurrence.
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Thing is, it's easy to find bad experience reports for all the products - including Garmin and Stratus. My guess is that results from the unknowable variables between airplanes, devices, connectivity, software, etc. If the Sentry does the trick I'm good - if not, I spent $500 on a GPS source - and the little Dual GPS devices are only a bit over $100 and rock solid in my experience. AT least Sporty's didn't nail me for state sale tax.
 
mandm said:
Sentry you have to set the zero point. They are decent but I wouldn’t try them in IFR, personally.
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If you're using the window suction cup mount for the Sentry and it falls down (happens to me on long flights), you'll need to recalibrate it. Your readings will be grossly incorrect until you do.
For that reason alone I would, in no circumstance, want to rely on that AHRS as a true backup unless I had no other choice.
Mine also periodically disconnects from my iPads and needs reconnection, which naturally is usually at the least convenient time. Upon reconnection it needs recalibration for the AI. Just something to be mindful of!
 
Not seeing a "calibration" instruction on my new Sentry. . .just powered it on and stuck it on my fridge; selected its WiFi on my iPad, and the AI came up. I goofed around with the mount- it's a Ram suction cup. My experience with them is good - haven't had one release. But I imagine that's an airplane specific variable. Sentry docs say the window is the best location, but the glare shield will work, too. I'll be testing it on my window.
 
Hmm, it should be there. When you're in the synthetic vision view on the iPad you should see a gear icon in the lower left hand corner. If you press that there should be an option to calibrate the AHRS. If you just take it's out of the box calibration then it may or may not be correct (and based on my experience will reliably be incorrect in-air w/o zero-ing it out when straight and level).

You're lucky you've never had it release! on my arrow window I have it fall onto the pax seat about once ever 2-3 hours or so.
 
Tom Wells said:
Hmm, it should be there. When you're in the synthetic vision view on the iPad you should see a gear icon in the lower left hand corner. If you press that there should be an option to calibrate the AHRS. If you just take it's out of the box calibration then it may or may not be correct (and based on my experience will reliably be incorrect in-air w/o zero-ing it out when straight and level).

You're lucky you've never had it release! on my arrow window I have it fall onto the pax seat about once ever 2-3 hours or so.
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Thanks, I'll take a look - Sentry comes with a minimal "quick start" booklet. I should look at FF and get that surrounded. Did yours come with a Ram mount/suction cup?
 
Sundancer said:
Thanks, I'll take a look - Sentry comes with a minimal "quick start" booklet. I should look at FF and get that surrounded. Did yours come with a Ram mount/suction cup?
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Yessir, mine came with the suction cup in the kit. It usually works great. Definitely better than the one I got for my goPro, that one is utterly worthless.
 
Got the Sentry - gave it a short (1.6 hours) tryout in our older Cherokee, mounted on left-side window. The AHRS worked fine, smooth, no lag. It was in-sync with our Aspen E5 all the time. I'll give it a longer look soon, but I think the range of experiences other pilots have had may depend on mounting/location variables? I dunno. I don't know the Sentry design specifics - I know there are incredibly small accelerometers available now - again, no idea of the quality of these for consumer electronics. I didn't pay much attention tot he synthetic vision feature yet.

I usually have my iPad mini in a knee board case - I'll have to move it up on a Ram mount. Speaking of, the suction cup worked fine for the fairly short flight. It would be a mess if it popped off at a time it was needed. . .
 
Tom Wells said:
If you're using the window suction cup mount for the Sentry and it falls down (happens to me on long flights), you'll need to recalibrate it. Your readings will be grossly incorrect until you do.
For that reason alone I would, in no circumstance, want to rely on that AHRS as a true backup unless I had no other choice.
Mine also periodically disconnects from my iPads and needs reconnection, which naturally is usually at the least convenient time. Upon reconnection it needs recalibration for the AI. Just something to be mindful of!
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Sundancer said:
Thanks, I'll take a look - Sentry comes with a minimal "quick start" booklet. I should look at FF and get that surrounded. Did yours come with a Ram mount/suction cup?
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I finally quit using the RAM suction mount, fell off too frequently. Bought a suction mnt from Pivot which stays put. Using Stratus. Not affiliated w/Pivot.
 
Thanks - just submitted a question via Flyboys about their 809PPK-PB mount and attaching the new iPad mini.
 
I use velcro to hold my Mini over the Aera 500 in the panel. Keep it simple.
 
RussR said:
A client of mine has now had two of these - neither one has worked right. It would bounce all around and usually not show the correct attitude anyway. I don't know the story of his calls back to Dynon, it's still on his panel but he never turns it on (and when I have, yeah it shows clearly erroneous information). His opinion of the product is not good.
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That was exactly my experience with the D1 way back in my Warrior days. Wasted 700 bucks in 2011. Vibration would gonk it out, attitude unreliable. It was an overpriced POS that never delivered for me, it doesn't surprise me their third generation still has the same basic problem. I've never flown behind a D10 (and present day variants) in their permanent panel mount solutions, but the performance of that Dynon left me real skeptical about installing anything Dynon for primary attitude information when I go the EAB route.

In fairness to Dynon, all these MEMS-based consumer electronic gizmos suffer from the fundamental unreliability inherent to calculating attitude based on external input for gravity vector (GPS or pitot a/s), as opposed to direct-sensing it like mechanical gyros or laser ring gyro driven presentations.
 
For a cheap and dependable back up AHRS and GPS nav that does not need to meet any TSO I would suggest considering using an old smart phone Velcro’d to instrument panel. There are plenty of free full feature EFIS apps with GPS moving map. I actually used my phone to fly across the country when I bought a plane…. Worked great and some apps have ability to depict WX and local ATC frequencies. Never had a problem getting a good GPS position, AND it has its own battery that last for hours should the USB power port fail, never an issue with over heating. Some paid for apps allow for depicting IAPs as well. I wifi connected it via my personal cell phone hot spot so to get internet connection for current info.

I would rather have this than a standby G5 or similar… and would argue it’s just as reliable and safer as it depicts terrain, nav commands, etc.
 
Sundancer said:
Our club plane has an Aspen AI/HSI, which I like pretty well. It doesn't require a backup AI for IFR, however, which I don't like quite as much.
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Just wondering about no backup AI. The Aspen needs an extended duration backup battery, in addition to software requirements in order to be legal for no backup AI.

I do fly with a Senty for an independent backup in case of complete panel failure however I do have panel mounted backups.
 
Mongoose Aviator said:
Just wondering about no backup AI. The Aspen needs an extended duration backup battery, in addition to software requirements in order to be legal for no backup AI.

I do fly with a Senty for an independent backup in case of complete panel failure however I do have panel mounted backups.
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Correct - our installation has the extended duration battery and the updated model. Not knocking it - it works fine, is easy to use, etc.
 
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