G3X- How do I get rid of the AOA tone on the ground?

[Desert Rat]

I calibrated my AOA this morning. While the calibration went well, The tone went solid during my 3 point landing (not unexpected, I guess) but stayed on for probably 5 seconds during the landing rollout.

Is there a way to tell the system that it's on the ground or do I need to re-calibrate it with less margin before the actual stall?

I did search for this before asking the question. Maybe I just missed it, but I didn't see where anybody has brought it up before.

PS- if you have this in your future, here's a tip; set the tone volume to something less than 50%. I thought that would be a nice safe middle of the road volume to start with and it's so loud in my light speed headsets that it's actually painful. I reset it to 30% and am going to give that a try

 

[dmattmul]

I calibrated my AOA this morning. While the calibration went well, The tone went solid during my 3 point landing (not unexpected, I guess) but stayed on for probably 5 seconds during the landing rollout.

Is there a way to tell the system that it's on the ground or do I need to re-calibrate it with less margin before the actual stall?

I did search for this before asking the question. Maybe I just missed it, but I didn't see where anybody has brought it up before.

PS- if you have this in your future, here's a tip; set the tone volume to something less than 50%. I thought that would be a nice safe middle of the road volume to start with and it's so loud in my light speed headsets that it's actually painful. I reset it to 30% and am going to give that a try

There is a setting to stop any audio tones below xx knots. This is for a Garmin system. If memory holds, I think 40 knots is the max number that can be used.

See Rev. AV Page 30-37

 

[mburch]

If memory holds, I think 40 knots is the max number that can be used.

Actually, the maximum limit for "Disable AOA on Ground Below" is dependent on what you have configured for "Enable AOA Above".

 

[bjdecker]

Actually, the maximum limit for "Disable AOA on Ground Below" is dependent on what you have configured for "Enable AOA Above".

The English Language is imprecise; The Olathe, KS dialect seems to be more so... I think Welsh is easier to understand.

The behaviors I'm looking for, but can't seem to get configured correctly are:

1. The AoA should "show up" when the aircraft is flying above a certain airspeed, say Vs0 - 5kts or so, and not rolling out, or taxiing, or taking off.
2. The AoA should "disappear" when the aircraft is flying above a certain airspeed - maybe 1.5*Vso or so --- (actually, I think this is good, Min Vis AoA parameter)

My numbers are:

Stall Speeds & AoA config	“Clean” Vs	“Full Flaps” Vs0	“Approach Flaps -- 15°” Vs1
V	54	47	52
Min Vis AoA (V * 1.5)	81	71	78
Caution Alert (V * 1.1)	60	52	57
Stall Warning AoA ( V )	54	47	52
Approach Target AoA (V * 1.3)	70	61	68

Admittedly, I fly faster than I should - but I don't need to get down and off in under 800'. I am typically dropping to 75kias over the fence, the AoA will never appear (Min Vis AoA is 71kias) -- no big deal, I'm flying too fast to care.

The "Disable AoA on Ground Below" value is set at 40kts now -- just a little annoyance while the aircraft decelerates on the roll out (AoA shows up during the flare/round out)
The "Enable AoA above" value is set to 60kts -- another bit of annoyance as the airplane blasts through Vs0 on the way to Vy or 120kias...

I would love for the AoA to shut off when the mains touch the ground regardless of the intended flight condition.

 

[mburch]

I would love for the AoA to shut off when the mains touch the ground regardless of the intended flight condition.

Well, your system already supports a squat switch... mechanical installation is left as an exercise for the installer!

 

[bjdecker]

Well, your system already supports a squat switch... mechanical installation is left as an exercise for the installer!

I’ve thought about it - can’t imagine a mechanism to capture wheel/gear travel to drive a switch. Maybe a wheel speed detector could do similar.

 

[scsmith]

...
2. The AoA should "disappear" when the aircraft is flying above a certain airspeed - maybe 1.5*Vso or so --- (actually, I think this is good, Min Vis AoA parameter)

Brian, why do you want to discontinue AoA above a certain speed? What about accelerated stalls? Maybe at least keep it active up to V_a.? (something like 2.45 x Vs) *
Above that, you will hit a g limit before an AoA limit. I would think AoA would be very helpful in dogfights.

* 2.45 is sqrt(6), so 6 g's at 2.45 Vs

 

[bjdecker]

Brian, why do you want to discontinue AoA above a certain speed? What about accelerated stalls? Maybe at least keep it active up to V_a.? (something like 2.45 x Vs) *
Above that, you will hit a g limit before an AoA limit. I would think AoA would be very helpful in dogfights.

* 2.45 is sqrt(6), so 6 g's at 2.45 Vs

Fair point Steve. However, I just don't operate the aircraft in those regimes. If I were to pull 6g's I'd be hard pressed (literally) to fly the airplane to a particular airspeed -- my mental energy would be on tightening my core, breathing, staying conscious, and trying to unload the a/c...

...also, I prefer the less is more UX on the PFD; less data and symbols distracting me from the task(s) at hand... (One of the reasons I prefer the Garmin over the Dynon.)

 

[Walt]

Brian, why do you want to discontinue AoA above a certain speed? What about accelerated stalls? Maybe at least keep it active up to V_a.? (something like 2.45 x Vs) *
Above that, you will hit a g limit before an AoA limit. I would think AoA would be very helpful in dogfights.

* 2.45 is sqrt(6), so 6 g's at 2.45 Vs

Agree with Steve, while practicing steep turns one day at around 120ish knots the AOA started letting me know I need to back off a bit, surprised me that I was getting that close to a stall at that speed!