Best artificial horizon app for Android

[birdus]

I'm doing my Private Pilot training and my Luscombe doesn't have an artificial horizon or turn/bank indicator. I plan on re-doing my panel next year, but need those instruments for my under-the-hood work while getting trained. My instructor told me I can use an app on my phone for those instruments, and I would prefer that since it's only an intermediate solution.

Is there a free or low cost app that would work well for that basic functionality? Also, I'm having a Stratus ESGi installed in a couple weeks. Can that feed my phone data for improved accuracy for these instruments, or are the two completely unrelated? I know it's got a WAAS GPS built in, but I wasn't sure if had accelerometers that could feed my phone better attitude data than what the phone can come up with on its own. I've got an Samsung Galaxy S8.

Thanks,
Jay

 

[David Megginson]

The accelerometers in a phone or tablet won't do it, but an external AHRS source will. Garmin Pilot in Android can take AHRS input from either my panel-mounted GTX 345 transponder or my portable GDL 51 SiriusXM receiver. Neither of those is especially a cheap solution, but there are probably other Android apps that can work with less-expensive AHRS options.

Note that AHRS over a wireless connection won't feel exactly like a panel-mounted AI, because the wireless connection introduces a bit of latency. Expect at least a 200–300 ms lag (say, one note in a Bluegrass lick) between the plane's movements and the wireless AHRS display. A lot of pilots say they don't notice it at all, but if you're a musician, video editor, baseball player (the kind of batter who can count fastball seams in a pitch coming at you), or anyone else who pays attention to small time slices, I guarantee it will be obvious to you.

 

[birdus]

Any way to feed that signal to my phone via USB to avoid the WiFi latency?

 

[mcmanigle]

For what it’s worth, modern iPhones (and I assume high end Android phones) have built-in electronic gyroscopes, as well as accelerometers. So while it will never be certified (or a good idea to use it in navigation in any way) there’s no reason an iPhone app couldn’t simulate an artificial horizon (via gyros) and turn coordinator (via accelerometers) pretty decently.

 

[Sinistar]

Both the Stratus and Garmin portable ADSB in devices have variants with AHRS. Some of the transponders do as well. What I have found is that the SynVis and AI widgets/gadgets render faster to slower in this order (using the same input device): iPads (the newer larger 10" ones are the fastest), then iPad Mini 4 and then the Android tablets. I sound like I am bashing Android but Android is the tablet I use on every flight. But if you want faster rendering speeds the later full size iPads (and probably iPhones) win because they run native code and faster processors. So far the best SynVis I have seen was a status on a larger newer generation iPad. It was almost fluid and it seemed like it was updating closer to 10frames/second vs the 5 you get from a Garmin device.

 

[Challenged]

Maybe check out Kwik EFIS, it's free so no harm in messing with it, but it's not going to work well without a Stratux (not Stratus) device: https://f-droid.org/en/packages/player.efis.pfd/

I can't seem to find what format the ESGi emits for AHRS, but the other one to check out would be iFly GPS, which has an instruments only display that ties into AHRS devices, but again not sure if the ESGi would be supported. I can post a message on their boards and ask for you though.

Ah, I see that I guess the ESGi system, just includes a Stratus 3 I guess, so I imagine iFly would work, as it's listed as supported here:
https://www.appareo.com/aviation/stratus-3-compatible-apps/

 

[David Megginson]

For what it’s worth, modern iPhones (and I assume high end Android phones) have built-in electronic gyroscopes, as well as accelerometers. So while it will never be certified (or a good idea to use it in navigation in any way) there’s no reason an iPhone app couldn’t simulate an artificial horizon (via gyros) and turn coordinator (via accelerometers) pretty decently.

Those are far too unreliable to use, even just for simulated IFR practice—I think it would be a frustrating experience.

 

[David Megginson]

Any way to feed that signal to my phone via USB to avoid the WiFi latency?

I haven't heard of a solution, but it might exist. You can hardwire a Garmin 660 portable to a panel-mounted device, FWIW.

But maybe the easiest thing would be just to buy one of these, and then recoup most of the cost by selling it used when you no longer need it (I can't find a single one on eBay right now, so you could probably command a good price when you sell it).

https://www.aircraftspruce.com/catalog/avpages/efis10-06727.php

 

[Tantalum]

built-in electronic gyroscopes, as well as accelerometers

Is this true? I have friends with iPhone 10 and Pixel 3 and 4 and you can easily spoof their "gyroscopes" by flying coordinated turns.. I'll have the plane banked over 30* and their app shows level flight. As far as I know these aren't actual artificial horizons.. it's basically just a fancy pendulum

You can also trick them into thinking you're banking by flying level but applying left or right rudder.. basically skidding

 

[dmspilot]

For what it’s worth, modern iPhones (and I assume high end Android phones) have built-in electronic gyroscopes, as well as accelerometers. So while it will never be certified (or a good idea to use it in navigation in any way) there’s no reason an iPhone app couldn’t simulate an artificial horizon (via gyros) and turn coordinator (via accelerometers) pretty decently.

Is this true? I have friends with iPhone 10 and Pixel 3 and 4 and you can easily spoof their "gyroscopes" by flying coordinated turns.. I'll have the plane banked over 30* and their app shows level flight. As far as I know these aren't actual artificial horizons.. it's basically just a fancy pendulum

You can also trick them into thinking you're banking by flying level but applying left or right rudder.. basically skidding

I think if it was so easy it would have been done already in a way that actually works correctly. I'm guessing there is some kind of auto-calibration algorithm applied at the operating system level that can't be overridden by an app, or the gyros are just not sensitive and accurate enough. Or both.

 

[birdus]

Is this true? I have friends with iPhone 10 and Pixel 3 and 4 and you can easily spoof their "gyroscopes" by flying coordinated turns.. I'll have the plane banked over 30* and their app shows level flight. As far as I know these aren't actual artificial horizons.. it's basically just a fancy pendulum.

Downloaded a free artificial horizon yesterday ("Aircraft Horizon Free"). Very responsive and looks fine for what it is. I just held my phone out in front of me and spun around until I almost fell over. When I tipped the phone over flat, it went somewhat cattywampus, as you'd expect. The bottom of the phone was pointing away from me. If it was just a pendulum, spinning around should've fixed it. Inertia, centripetal acceleration, and all that. There didn't seem to be any effect. So, at least with the Samsung Galaxy S8, it doesn't seem to use "a fancy pendulum."

I'll stick it in the plane and we'll try it out, just for fun. In any event, I'll have the Stratus ESGi installed within a few weeks, so apparently I can just use its AHRS info and whatever app supports it.

 

[RyanShort1]

This is the concern I was mentioning for the checkride on your other thread. Whatever you do for the solution, look for something your examiner will accept for the checkride. It makes no sense to pay a little for a short-term solution if you need to spend more money, or aircraft rental costs for the checkride.

 

[birdus]

This is the concern I was mentioning for the checkride on your other thread. Whatever you do for the solution, look for something your examiner will accept for the checkride. It makes no sense to pay a little for a short-term solution if you need to spend more money, or aircraft rental costs for the checkride.

Ah. Okay. I'd forgotten. My instructor was just saying I needed it for pre-solo (although I didn't see in the FARs where instrument work was required for solo). In any event, I'll go ahead and check to see if I'll need something like that for the check ride, and make sure to have something working which uses the AHRS signal from the Stratus. In fact, now that I think of it, a friend of mine did his check ride with the same person. He has a Champ with no electrical. I think he has a Stratus ADSB and maybe fed it to an iPad. I'll ask him about it to make sure I'm ready to go for the check ride.

Thanks!
Jay

 

[RyanShort1]

I don't recall or see a requirement currently for instrument training pre-solo in 14 CFR 61.87... but you'll need it before cross-country solo per 14 CFR 61.93
Which brings up the point that the instructor needs to be teaching you the regs accurately, and you need to be reading them on your own whether he is or isn't to make sure you know what is required of you and that you're getting ready for said checkride.