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Who flies AOA, and what system do you use?

moespeeds

Well Known Member
Friend
This thread might fit better in the Glass Cockpits section, but I wasn't sure. Feel free to move it.

Who's flying using an AOA gauge, and what system do you use?

https://www.youtube.com/watch?v=8JcjWnAJGKQ

I was pretty disappointed in the lack of AOA vendors at Oshkosh this year. I currently use the Advanced Flight Systems AOA that is displayed on my AFS 4500. After getting used to it, I'm blown away that there isn't one in every GA aircraft flying. It's an amazing instrument.

I'm switching to a G3X in the fall, but I'm put off by the fact that their AOA system doesn't account for flaps down/up as it does have an impact on your critical AOA.

I'm seriously considering the Alpha Systems setup, and a Garmin installer who happened to overhear my discussion with the Garmin rep pulled me aside and told me the Alpha setup is far superior to what Garmin offers. https://www.alphasystemsaoa.com/
 
I fly with my Dynon AOA. You may get limited answers as most of don’t intentionally fly on the edge with it. If that is what you want look into Onspeed (posts here often). They are cutting edge right now.
 
I'm switching to a G3X in the fall, but I'm put off by the fact that their AOA system doesn't account for flaps down/up as it does have an impact on your critical AOA.
]

I would like to understand how flaps up/down impacts critical AOA.
 
Take a look at the FlyOnSpeed.org site. There is a lot of information regarding AoA and testing of the FlyOnSpeed system in particular and the advantages of flying with AoA. The project has identified some of the weaknesses of the FlyOnSpeed system as well as AoA systems in general. I think that your time will be well spent in taking a look at the information regardless of the system you choose.

- larosta
 
I use the AOA Sport, it’s a stand alone system not interfaced to my EFIS. I installed it when I built my airplane back in 2003, it works flawlessly and accounts for flaps. I don’t know if it’s still available.
 
Let’s see - the answer to your first question is an emphatic “yes!!” - we have AoA in all five of our flying aircraft, and the only thing I use the ASI for is to make sure I am slow enough to deploy flaps (and gear in case of the little jet) - AoA is the primary instrument for everything else.

We’ve got two airplanes with AFS AOA Pro glareshield displays, a Dynon Skyview airplane with display on the screen - but more importantly, audio, two Garmin airplanes with audio, an MGL airplane with on-screen AoA. Getting an “On-Speed” from Vac installed as soon as I catch up from OSH. Oh yeah - the Dynon airplane also has an Alpha Systems on the glareshield.

The bottom line, in my opinion, is that anything is better than nothing, and they al work - even if they aren’t compensated for flaps. In that case, calibrate them with flaps in landing position for the most protection in that environment. Also my opinion is that Audio is superior to visual, because you’re always looking into the turn, and away from the screen or glare shield when turning, and that is when you are more likely to stall.

If you’re getting an EFIS, get an AoA probe with it, and that’ll get you started.

Paul
 
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AFS Pro upper left side of panel so it can be in my FOV during the 180* descending turn to final (just like them Navy carrier pilots).

It’s my primary landing instrument. Airspeed is secondary.

Pic of my panel:
https://dougreeves.smugmug.com/RV-Panels-High-Res/i-LQtTQmQ
i-LQtTQmQ-XL.jpg


V/r,dr
 
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5:50 seconds into the AOA video linked in my OP.

Okay, I get it, thank you. The section of the wing with deployed flaps has a smaller critical (stall) angle than the no flap part of the wing. But obviously the differences are not huge, or none of the uncompensated devices would work.

Doug: Did you mean upper left? [yes! Fixed now.v/r,dr]
 
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Been very happy with the G3X. It's included with the system so basically free, no installation other than an AOA line, easy to calibrate, good audio output,
optional GI260 display for glareshield mounting (displays on the PFD also).
It works great so what's not to like?
 
AOA in the G3X

I calibrated mine with partial flaps thinking that was worst case scenario. How often do I land no flaps? I'll be honest with you when I made the turn to final at OSH at 150 ft (They must think I'm a bush plane) and heard the AOA start to chime I pushed forward and added power. My wife told me she never saw me do that before but glad I did. AOA is a very nice safety device in my opinion and easy to install and use. +1 to Alex De Dominicis (http://rvtraining.com/) who let me practice that approach in his RV-10.
 
I have GRT equipment. It's important to understand that GRT has "computed AOA" available on all their EFIS devices. GRT also offers "sensed AOA" on their more modern EFIS devices. I have the latter, using a third, differential pressure input going into the Adaptive AHARS.

GRT doesn't put the AOA display up on the screen until it senses AOA is getting closer to a critical level, then it pops up the AOA display. The display is useful however, as others have mentioned previously, an audio tone allows one to be attuned to AOA while keeping the eyeballs completely outside the cockpit. The GRT equipment produces a beeping tone that works very well for me. A 1.3Vso approach results in zero tones. A 1.2Vso approach results in slow beeps which increase in rapidity as energy bleeds off in the landing flare.

I've had the AOA tones go off while in maneuvering flight only once and wow, did they get my attention!
 
GRT AoA

I have GRT equipment. It's important to understand that GRT has "computed AOA" available on all their EFIS devices. GRT also offers "sensed AOA" on their more modern EFIS devices. I have the latter, using a third, differential pressure input going into the Adaptive AHARS.

GRT doesn't put the AOA display up on the screen until it senses AOA is getting closer to a critical level, then it pops up the AOA display. The display is useful however, as others have mentioned previously, an audio tone allows one to be attuned to AOA while keeping the eyeballs completely outside the cockpit. The GRT equipment produces a beeping tone that works very well for me. A 1.3Vso approach results in zero tones. A 1.2Vso approach results in slow beeps which increase in rapidity as energy bleeds off in the landing flare.

I've had the AOA tones go off while in maneuvering flight only once and wow, did they get my attention!
Same here - I needed to exit the pattern while turning downwind to base due to bad spacing on my part, and my GRT AoA urged me to not get too slow. It reminded me how easily a bit of inattention can lead to a very bad day.
 
When I got my 8 (completed) the AFS AOA system was not hooked up. I hooked it up and calibrated it, and was shocked at how far into the red I was going when I turned base to final while doing no flap landings.

Flaps down does make a difference. That's why I want a system with at least 2 calibration points. It's also nice when just hamming around doing loops and such to see how close to the accelerated stall you are.

A multi-point system will also give you best climb and glide with no flaps.
 
I use an Advanced Flight 5400 with built-in always-displayed AoA. I view the audio tones as being a safety backup…I actually fly the gauge as I turn base and start slowing down. I think that those are the turns that have the best chance of killing me.
 
When I built my 7A I chose the "Lift Reserve Indicator" which is purely air pressure differential based and has no electric requirement. That was a deliberate choice so that in the event of a failure of my 2-screen EFIS panel I could still land safely. The device works very well but does not have audio.
LRI.jpg

I don't know if that device is still sold but my purpose is to answer the question. And, YES I do think AOA is something all aircraft should have. I will probably add it to my Dynon in the 12 I recently purchased, even though it has an audible stall horn.
 
I'm getting used to the AoA functionality that came built into my AFS avionics suite. The calibration process was challenging for me: my own inability to follow directions well, combined with some button-pushes that were either too short or too long resulting in only half the data (flaps zero) being saved. Oh well, so I got to fly the zero lift parabola twice - no biggie.

It's nice (and instructive) in the pattern and has helped confirm the appropriateness of my habitual airspeeds in different segments of the landing pattern. What has surprised me is the "Angle, angle, PUSH!" warning I get at rotation on every single takeoff. Apparently at Vrot we are typically operating our airfoils at AoA that would be excessive when landing versus takeoff, and it is engine thrust and ground effect that keep us out of a stall as we break ground. At least this is true for the flying style I have adopted. Before AoA, I never knew I was kind of horsing the -10 off the runway when it reached 65 KIAS.

My takeaway from listening to the AoA warning throughout the first 50 feet of climb-out is how important it would be to unload the wing immediately in event of a power loss on takeoff - I'm already in what would be power off stall territory and ground effect is rapidly vanishing in the early climb. To fail to do this would put one in a pancake attitude before you could blink.
 
I'm getting used to the AoA functionality that came built into my AFS avionics suite. The calibration process was challenging for me: my own inability to follow directions well, combined with some button-pushes that were either too short or too long resulting in only half the data (flaps zero) being saved. Oh well, so I got to fly the zero lift parabola twice - no biggie.

It's nice (and instructive) in the pattern and has helped confirm the appropriateness of my habitual airspeeds in different segments of the landing pattern. What has surprised me is the "Angle, angle, PUSH!" warning I get at rotation on every single takeoff. Apparently at Vrot we are typically operating our airfoils at AoA that would be excessive when landing versus takeoff, and it is engine thrust and ground effect that keep us out of a stall as we break ground. At least this is true for the flying style I have adopted. Before AoA, I never knew I was kind of horsing the -10 off the runway when it reached 65 KIAS.

My takeaway from listening to the AoA warning throughout the first 50 feet of climb-out is how important it would be to unload the wing immediately in event of a power loss on takeoff - I'm already in what would be power off stall territory and ground effect is rapidly vanishing in the early climb. To fail to do this would put one in a pancake attitude before you could blink.

That is a valuable insight! We tend to stay in ground effect and accelerate to 110 knots before climbing out. This helps with cooling too.
 
It is too bad the Onspeed AOA has got so many supply chain issues.

I would of built it months ago.

Perhaps they will do a redesign with different components or a commercial unit.
 
Perhaps they will do a redesign with different components or a commercial unit.
All commercial operations are having the same issues with the supply chain. Redesigning to use different components is really the only option.
 
This question is for everyone, but Paul in particular. Presently finishing up my RV-14A QB wing and installing Garmin GAP26 Pitot/AOA. I am not planning to install the traditional stall warning horn provided by Van's. I am interested to know what any of you think of my decision. Thanks.
 
stall warning

I installed the stock stall warning and the G3X AOA.

I removed the stock warning during phase 1, as it was a nuisance, provided no additional information, and most importantly, removed a piece of metal protruding from the LE of the wing. You won't be happy if you walk into it...:rolleyes:
 
This question is for everyone, but Paul in particular. Presently finishing up my RV-14A QB wing and installing Garmin GAP26 Pitot/AOA. I am not planning to install the traditional stall warning horn provided by Van's. I am interested to know what any of you think of my decision. Thanks.

I’ve been flying for nine years with just an AOA in my RV-10. The stall warning is redundant.
 
OnSpeed AOA on a C-177 automatically individually calibrated for each flap setting. You can see the display on the right side, but using the stereo tones in the headsets is easier plus it gives you out of trim yaw indication in the headset too.
 

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I'm another one who installed the stall warning switch and ended up removing it. As other's have said it's a redundant nuisance.
 
Pretty much any AoA system is superior to a vane-type stall switch, and for my purposes, I have no need for one, since I use AoA on all my planes.
 
Thanks for all the feedback folks. Will continue onward as planned installing AOA and filling the holes on the leading edge intended for the stall warning horn. Getting closer every day to that first flight.
 
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