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Annoying Dynon AOA alarm

RV10Rob

RV10Rob

Well Known Member
I have the Dynon AOA installed in my RV-10. The problem I'm having is that after landing, the AOA is often in the "red" until airspeed goes to zero. This means that with sufficient wind to activate the airspeed indicator (generally 15kts or more), I hear "stall, stall" until the wind dies down, which is sometimes not until I get to my hangar. Anyone else seeing this issue in their RV? It's really annoying, especially with passengers.

There is a minimum speed setting for the alarm, but according to Dynon and my own observation, the alarm will continue to sound until the high AOA indication is eliminated (or the airspeed goes to zero).

-Rob
 
Rob,

I have the D10A installed in my RV-7A using the Dynon heated pitot, and upon completion of the calibration procedures, the alarm tone only sounds when a stall is immenent (just above the red) ... Once I'm on the ground and the wing's lift is gone, the tone no longer sounds, it seems to work consistantly well. However, until such time that you can get the calibration done to your satisfaction, I think that you should be able to silence the tone alarm in the set-up.

Victor
 
Yes this is just how it is...there is no way to calibrate it out.

Mine is calibrated to dead nuts on the stall but it does this to.

It is really bad on TW planes. Most of the time I have the alarm all the way to the turn off the runway.

The minimum air speed setting controls how fast you must be going before the alarm will arm. There currently is no setting for after it is triggered, it just goes till the pressures come back in line.
 
Thanks, guys... I can't imagine why Dynon would have done this. The alarm should just be off below the minimum speed, under all circumstances.

-Rob
 
So the reason we did it this way was that we wanted to not discard actual in-flight stall cases where airspeed decays, but where the aircraft IS actually stalled and in the air, such as can be experienced in a deep stall with minimal airspeed (especially possible with cub-like aircraft). So the minimum speed setting is ignored if the alarm was already blaring as the minimum speed threshold is crossed as airspeed decays, but its heeded if airspeed is coming up from zero. This means (as you're finding) that not every nuisance case may be dealt with in every airplane. It was essentially an attempt to minimize nuisance alarms without compromising corner cases which could actually happen in-flight. Most airplanes' AOA indicators essentially go back to yellow/green on the roll-out, but this is aircraft/calibration-specific. We've only had a a few complaints like yours over the years, so we thought we've had the right balance. So no promises we'll make any changes here, but we'll continue to keep our ears open. Anyone else having this issue?

Mike S
Product Manager
Dynon Avionics
 
dynonsupport said:
So the reason we did it this way was that we wanted to not discard actual in-flight stall cases where airspeed decays, but where the aircraft IS actually stalled and in the air, such as can be experienced in a deep stall with minimal airspeed (especially possible with cub-like aircraft). So the minimum speed setting is ignored if the alarm was already blaring as the minimum speed threshold is crossed as airspeed decays, but its heeded if airspeed is coming up from zero. This means (as you're finding) that not every nuisance case may be dealt with in every airplane. It was essentially an attempt to minimize nuisance alarms without compromising corner cases which could actually happen in-flight. Most airplanes' AOA indicators essentially go back to yellow/green on the roll-out, but this is aircraft/calibration-specific. We've only had a a few complaints like yours over the years, so we thought we've had the right balance. So no promises we'll make any changes here, but we'll continue to keep our ears open. Anyone else having this issue?

Mike S
Product Manager
Dynon Avionics
Click to expand...

It happens when landing into a brisk wind blowing right down the runway, the system thinks the plane is still in a stall even when taxiing at moderate speed (RV-6....taildragger, of course).

Otherwise, I like the system, it works well with the LRI probe.
 
If you placed a "T" in the AOA line and then opened that line when alarm was not needed, it should shut off the alarm. A push to open and release to close would be best.
 
Yes, I get the alarm when landing and it stays on almost to rollout. Also get it on takeoff but it goes away fairly quickly....
Flying an RV-8
 
gator said:
Yes, I get the alarm when landing and it stays on almost to rollout. Also get it on takeoff but it goes away fairly quickly....
Flying an RV-8
Click to expand...

It's more important to pay attention to it on takeoff than on roll out.
 
To explain our logic:

There is a minimum airspeed setting for AoA to trigger. You must be going faster than this and have AoA above your threshold to hear the AoA alarm.

What we will not do is CANCEL an AoA alarm that is going off at the time that airspeed goes below the threshold. However, if the AoA drops while you are slow, then the AoA alarm will stop and should not come back unless you speed up.

If you're getting AoA alarms that are going from off to on while below our speed threshold, then we have a bug. If they are persisting as you slow down, then that's by design, but of course we are willing to reconsider. The AoA has been like this on these products for 3 years, but we've sure never been aware that it was causing issues like this.

--Ian
Dynon Systems Engineering
 
Ian,

I am pretty sure the logic works fine on the minimum speed to arm the AOA alarm, at least on 5.4 and in my plane it does.

The issue with the alarm continuing to sound all the way to little to no speed is not new, it goes back some time, quite a few questions about it in the archives of the Dynon forum.

I just accepted that this was the way it had to be in order to warn someone that is in a very deep stall.

Maybe you could allow the AOA Alarm to be acknowledged or silenced with a button push?
 
+1 on the button push

same issue with my -7, the button push would be consistent with the process to remove other "latched" alarms on the Dynon.
 
We don't have the AOA in the RV-8 but I did wire up the Dynon's audio alerts thru a potentiometer (volume control) hidden away under the bottom left side of the panel, making it easy to reach under there and give it a quick twist to silence the alerts ;)
 
Most of the time I just ignore it once the wheels are down but it can make it hard to hear the tower controller's instructions on when to turn off and contact ground so I keep mine turned down lower than I would like. I can't reach my volume pot while strapped in.
 
Mine has this problem also. While annoying I'm used to it, but my new passengers don't think so highly of it. A button press to silence would be great.
 
Works perfect

in my 7.
I calibrated the D10A AOA 3 years ago and have not experienced any nuisance alarms. I do plenty of stalls and get a solid tone just prior to the stall buffet.

Bill
RV-7 N151WP
Lee's Summit, MO
 
I get the nuisance alarm when I do a full stall 3 point landing. When I wheel land and gradually lower the tail I never get the alarm.
 
NO Alarm

taking off or landing. I do some transition training and stalls are part of the package. The AOA alarm is set to go off at the top of the yellow, which is does and is just an instant before the stall buffet. A friend in the adjacent hangar has a 7A with a D10A. It also appeared to function the same as mine during his flight review.

Best regards,

Bill
RV-7 N151WP
Barrett IO-390
Lee's Summit, MO
 
Brian,
In my experience, most people do not get this alarm. I've ridden in plenty of Dynon AoA equipped airplanes with working audio alerts and have never experienced this. It seems to be somewhat dependent on the airplane and the calibration.

--Ian
 
7 planes so far in this little thread alone.

I understand why it is the way it is and live with it....

The silence button is just a suggestion.

Mine does not do it every landing. Only on three pointers with a good headwind. I doubt trikes ever have this issue once the nose wheel is on the ground.
 
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Dynon aoa nuisance alarm

Just installed and calibrated my new Dynon AOA system. Works great except that I cannot configure it so that the alarm stops below my "min speed" setting.
It stays on throughout the rollout which is very annoying to say the least!
I noticed a few comments regarding tailwheels, and am thinking my T/W RV8
wing never leaves the stall regime because of its aoa on the ground after a 3 point landing.
Dear Dynon...please design a kill switch for the audio alarm!
 
I have never heard of this issue before. I have the same configuration as Rob. Never had it occur once.

I can only assume it is a configuration issue. My AOA is configured for a deeper stall? I definitely get into the yellow but can't recall if I ever flare into the red at least not consistently.

Jae
 
I've never experienced the problem. Mine comes on just before touchdown and goes off when solidly on the ground. 90% of my landings are 3-point. D10A with homemade pitot/AOA. I don't see how the homemade pitot could make a difference.
 
Both SkyView and the D10/D100 have low speed inhibit settings. Page 4-17 of the SkyView install manual, and page 7-31 of the D10A manual.
 
dynonsupport said:
Both SkyView and the D10/D100 have low speed inhibit settings. Page 4-17 of the SkyView install manual, and page 7-31 of the D10A manual.
Click to expand...

The following is quoted from the D10 Install manual, page 7-31:

"While in the menu, press MINSPD to configure the minimum airspeed at which an AOA alarm can occur. Anytime airspeed is below the MINSPD value, AOA alarms will not occur; anytime it is above the MINSPD value, alarms can occur. If the AOA alarm is already sounding as airspeed falls below this threshold, it will continue to sound until the high AOA condition is resolved."

Unfortunately, this will not resolve the problems discussed in this thread. The software feature described in the last sentence quoted above is what causes the alarm to continue to sound when taxiing a tailwheel aircraft in a moderately strong breeze.

Dynon....we need an ACK button to silence the alarm when it becomes a nuisance. Thank you.
 
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It is amazing to me how hard it is sometimes to get a point across of these forums. This has been discussed for years now and someone from Dynon totally missed the point.

Sam got it though!

As usual the point is buried in the details.
 
I agree with Sam, this is super annoying, distracting and unnecessarily alarms passengers. Please fix this. Today on roll-out tower was trying to switch me to ground but the 'stall stall stall' drowned them out.
 
I asked for one little add on for my XTreme...............

and there it was in the next upgrade that I downloaded on my SD card and placed in the front access slot on the face of my XTreme.

This technology is amazing!
 
It's been a year since my original post, and the problem is still there and still annoying. We just need a setting for an airspeed below which the AOA alarm is disabled under all circumstances. The only thing that has changed in the last year is that I've gotten really good at going into the setup menu and disabling the AOA alarm after landing. I'm somewhat less good at remembering to re-enable it later.

-Rob
 
I'm sorry that I missed in the recent revival of this thread the fact that the poster already mentioned the airspeed switch. I was responding after hours when I was in a rush and I wasn't reading as clearly as I should.

There is a difference between SkyView and the D10/D100 series. SkyView doesn't have the "continued" alarm, so I wasn't sure which system the poster had since it wasn't mentioned.

As for the D10/D100, I'm sorry that the system doesn't work perfect for everyone. Updating the D10/D100 is something we do rarely now, and is expensive for us in terms of time. The last feature update was over two years ago, but we do have a release planned, and I'll do my best to get this change put in.

--Ian Jordan
Dynon Avionics
 
Rob,
Unless I mis-read (always possible) you are the only nose wheel aircraft with this issue. Tail draggers I understand, they sit at high angles of attack. In my 10 the alarm comes on in the flare, but goes off as soon as the nose comes down to the runway. I do not recall where my minimum speed is set (D6).
Bob
 
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