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AOA Indicators

tentoes

Member
Hi I was just curious to know if anyone uses Angle-of-Attack indicators in their Van's? I'm guessing they are in way more use in the heavier aircraft but thought I might ask.
 
There are quite a few around, since most of the newer EFIS boxes include them. I think I’m in the majority in favoring audio warning tones over the visual display.
 
Yes. My 10 year old Advanced Flight 4500 EFIS had it built into the display, as does the Advanced Flight 5400 EFIS that I recently replaced the original with. I think that most modern EFIS's have AOA capability (Advanced Flight, Dynon, Garmin, GRT). It's also available as a stand-alone indicator from several manufacture (sits on the glare shield) and both visual and aural warning is common (increasing beep frequency as stall approaches, and mine also provides the "angle-angle-push" warning as stall becomes imminent.

AoA as a stall warning device, appears to be increasingly a preferable choice over just relying on airspeed.
 
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I have an Advanced Flight Systems Sport LED AOA horizontal ladder on my glare shield. It would be the last instrument I would want to be without.
 
Hi everyone.....thanks for all of the feedback! I can see scenarios where an AOA indicator could be a real life-saver, like in an engine failure on takeoff and that sweet, "soft" runway that you just took off from SURE looks good.....
To 00Dan: that site looks really cool! Isn't that basically a site to show how to do a DIY AOA indicator? That is a cool resource! Thank you!
 
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The Dynon AoA indicator on our PFD is probably the best safety feature we could have on any aeroplane.

Properly calibrated, it lets you know exactly how you stand regarding flying or falling !

It goes back to basics and you can play with it up aloft to garner a lot of safety info.

Stick position relates to AoA, relates to stall, relates to falling.....:D

Calibrating it is an absolute hoot - full power stalls had my Brother squealing like a girl !

:D
 
Hi I was just curious to know if anyone uses Angle-of-Attack indicators in their Van's? I'm guessing they are in way more use in the heavier aircraft but thought I might ask.

My ship came with G3X and the external AOA indicator on glare shield, which also has aural output. I never really used AOA before, even in large aircraft - it was there but never paid much attention. I absolutely love it! I don't look at the IAS during landings much anymore.
 
Don't forget to do an AOA crosscheck against Airspeed indication entering the pattern

I would suggest everyone who uses AOA during their flying crosscheck the AOA indication versus a known airspeed on downwind before betting their lives on that indicator. AOA indicators are VERY reliable but do occasionally fail. All it takes is a blocked port due to bugs or icing. I have flown thousands of hours in US Navy aircraft on and off the carrier and our procedure required an AOA crosscheck on our first downwind out of the break to verify proper AOA operation. After that, we flew primarily AOA. I would gladly remove my airspeed indicator before removing an operating AOA in the carrier environment.
 
Hi everyone.....thanks for all of the feedback! I can see scenarios where an AOA indicator could be a real life-saver, like in an engine failure on takeoff and that sweet, "soft" runway that you just took off from SURE looks good.....
To 00Dan: that site looks really cool! Isn't that basically a site to show how to do a DIY AOA indicator? That is a cool resource! Thank you!

Read this thread: https://vansairforce.net/community/showthread.php?t=196593

The website goes into more details but the short version is the FlyONSPEED system is much more robust than any of the EFIS-based systems mentioned in this thread. I strongly recommend you consider it.
 
AOA is always useful regardless of weight. Indirectly all certified planes have stall warning which is AOA based. Critical AOA is stall and is the same regardless of weight. It is stall speed that varies with weight.

Seeing the how close you are to critical angle of attack (before stall) is a good thing.

As said most EFIS you can buy for a EAB kit plane has an option for AOA sensor and display. There are also many AOA stand alone systems as well. Many kit planes don't have stall warning or AOA. Personally a stall sensor or AOA should always be installed.
 
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AOPA just did a webinar about back country flying, going into very short strips, with numerous commentators. Guess what? AOA was never mentioned...
 
?? AOA display on Garmin PFD - GDU465

I have a G3X suite installed in my RV-14A and am going through configuration of the system. The part that I am working on now is the AOA configuration. The pieces concerned are the GAP26 (Pitot/AOA probe), the GSU25 (air data computer), and the GDU465 (PFD).

After reviewing the configuration instructions for the Garmin AOA, I am sorta-kinda-certain that the AOA tower bar graph will display on the PDU, but I have not found a picture of a screen display in any Garmin marketing or Pilot's Guide depicting that.

Am I correct or is a GI260 (AOA indicator) required for display of the indication?

If anyone has a captured screen shot of the AOA indication on a PDU that would be helpful.
 
sorta-kinda-certain that the AOA tower bar graph will display on the PDU, but I have not found a picture of a screen display in any Garmin marketing or Pilot's Guide depicting that.

Am I correct or is a GI260 (AOA indicator) required for display of the indication?

Correct -- it's displayed on the PFD; see the pilot's guide, page 88. Picture attached.
 

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Thanks Brian, I have looked at so many docs pages, I probably saw this a flew right by it. I'll review.
 
AOPA just did a webinar about back country flying, going into very short strips, with numerous commentators. Guess what? AOA was never mentioned...
What does that have to do with the value of an AOA? What is your point?
I did not hear this back country "webinar", who spoke and what did they say?
There is a lot to "back country flying" and only so much can be fit in an hour.
Did they get into aircraft aerodynamics, and STOL equipment? Weather? Performance?
All Navy Planes, at least ones flown off the boat have AOA. Aircraft Carrier is the ultimate Back countrty.

37 years ago no one was talking about GPS in GA airplanes.... does that mean it was not going to be golden decades later? May be AOA should be focused on now for the future. Have you flown with AOA? I think I know the answer...

Would AOA indication reduce stall and stall spin accidents? Landing accidents? Most planes give indication of impending stall. If a pilot has good "Seat of Pants" feel and good scan and interpretation of basic flight instruments, they know if they are mushing or near stall. Some planes are a little more abrupt giving less warning. Some pilot may not be skilled or is distracted may need a BIG RED AOA warning in their face? AOA is not strictly required or sacrosanct, but it is a valuable tool.
 
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AOPA just did a webinar about back country flying, going into very short strips, with numerous commentators. Guess what? AOA was never mentioned...

I think just because AOPA didn't mention it doesn't mean it not important. The emphasis of discussion was about the spate of accidents due to the high density altitude when flying in the mountain that flatland pilots aren't used to.

This guy flies his 182 into sandbars where STOL specific airplanes land. He swears by his AOA.
https://www.youtube.com/user/motoadve
 
What does that have to do with the value of an AOA? What is your point?
I did not hear this back country "webinar", who spoke and what did they say?
There is a lot to "back country flying" and only so much can be fit in an hour.
Did they get into aircraft aerodynamics, and STOL equipment? Weather? Performance?
All Navy Planes, at least ones flown off the boat have AOA. Aircraft Carrier is the ultimate Back countrty.

37 years ago no one was talking about GPS in GA airplanes.... does that mean it was not going to be golden decades later? May be AOA should be focused on now for the future. Have you flown with AOA? I think I know the answer...

Would AOA indication reduce stall and stall spin accidents? Landing accidents? Most planes give indication of impending stall. If a pilot has good "Seat of Pants" feel and good scan and interpretation of basic flight instruments, they know if they are mushing or near stall. Some planes are a little more abrupt giving less warning. Some pilot may not be skilled or is distracted may need a BIG RED AOA warning in their face? AOA is not strictly required or sacrosanct, but it is a valuable tool.

Lots of nice rhetoric in here but…
* Carrier approaches are wildly different from GA landings in many, many ways. Comparing AOA for those to GA makes little to no sense from a flight dynamics point of view nor from an operational point of view. Carrier landings are designed for high repeatability to reduce risk, GA is flown with high variability for flexibility and utility.
* At my AOPA/ASI presentation at Oshkosh this year (https://www.youtube.com/watch?v=7C2xfFNb1sQ), I talked about various kinds of base to final accidents, including low AOA, ball centered loss of control. The short answer is that if pilots practice a deliberate runway overshoot (with a CFI), just as pilots practice go arounds, LOC base to final would probably decrease, because there are major psychological factors in play.
* Have you ever noticed that AOA videos always seem to be taken in calm winds and straight in? Two reasons are that AOA has non-linear lead/lag characteristics, meaning it can have inconsistent guidance characteristics in smooth versus aggressive flying; and AOA can have wild variation in turbulence. I presented all that at a Sun ‘n’ Fun forum a few years back, but it was not recorded. There were flight dynamics engineers and a DAR in the audience, and they had no argument with what I presented. Here’s a short video showing AOA noise in nominal wind conditions: https://www.youtube.com/watch?v=bWSzptdQyFk

I have a progressive aural stall warning in my RV-9A and like it. Then again, I did not have any AOA warning of any sort in my RV-4, RV-8, RV-8A or AirCam and did not miss it. I have a visual AOA on the PFD of the RV-9A and never use it. And as for a glareshield display, that might not be in your primary field of view when you’re not on final, even if it were not for its inherent limitations mentioned above.

Really, I think the issue is not technical, it’s psychological. Think back to the fork-tailed doctor killer of the 70s (Beech Bonanza) when those accidents were dysfunctionally addressed by the Beech pilots. There are numerous instances in the homebuilt world today in which a pleasant ownership experience is mis-stated as a reflection of the airplane’s virtues – or the avionics’, or of AOA. Some of the comments in this thread are more psychological than technical.

Anybody who wants to come fly the Expanded Envelope Exercises® with me in Savannah, drop me a line. The cost is that you buy lunch.
 
I respectfully disagree with you Mr Wischmeyer. I have absolutely no doubt that AOA indicators could save lives for the GA community.
 
Lots of nice rhetoric in here but.
Yes lot's of rhetoric, yours. Ha ha. Your point? You took this discourse on a massive non sequitur. 1st you say a backcountry flying webinar you heard didn't mention AOA indicators? mountainflying and AOA You're upset about EAA picking “gadgets” over your training maneuvers. I sympathize. However AOA is not a panacea to reducing LOC accidents or well trained pilots. It indicates when are near critical angle of attack (stall). It doesn't change with weight, density altitude or g-load. AOA to give you best Vy, Vx, L/D max in all conditions.

AOA indication in the cockpit or any "gadget" is NEVER a substitute for airmanship, looking out the cockpit, scanning flight Inst., situational awareness and stick-N-rudder skill. GPS is not a substitute for PIC responsibility to navigate; Autopilot not a substitute for flying skills in VFR or IMC. Tools that aid a pilot do improve safety is good.

Promoting & marketing "E3" (Enhanced Envelope Maneuvers) the EAA Founders Innovation judges didn't appreciate your rehashing existing training exercises: Steep turns, S-turns, Dutch rolls, turning stall recovery, descending spiral recovery (i.e., spiral / unusual attitude) recovery, you coined “E3”. How useful are your training exercises over others is a debate for another time, but complaining about EAA’s lack of vision isn't going to win'em over.:

* “contest, seems overly focused on gadgets…. there is a better way to “inoculate” pilots against the dreaded LOC disease….a series of exercises "E3".
* “Would I like to win the $25,000 prize next year? Of course! Both my ego and bank account encourage me to keep trying.”
* “E3 made [] EAA Founder's Innovation Prize contest [finals]…., judges at EAA Founder's Innovation Prize competition did not appreciate the E3 vision, [awarding] top 3 prizes to hardware devices.”

Ed I sympathize. As a lifetime EAA member they have disappointed me from time to time. Your E3 branded exercises are not 100% original or “revolutionary”. I disagree CFI's are incapable of grasping your maneuvers w/o specialized E3 training. You insisting FAA should make your exercises mandatory comes off grandiose. I appreciate your moxie but disagree with your orthodoxy. Students are individuals, and one size or set of exercises doesn't fit all. No one thing will impact LOC accidents. BTW the Jan 2022 Sport Aviation has an Article on AOA and referencing Mike Vaccaro EAA Founders Innovation Grand Prize winner. BTW Richard VanGrusnven advocates AOA.

Stalls in pattern has been a big LOC accident category, since the dawn of aviation. The proverbial “Base to Final” stall has been a caution I heard before and since I was a pilot. I flew with my WWII pilot Dad as a kid in a Piper. I recall him saying “Son you have to watch base to final stalls.” I could not reach the rudders but knew since age 6 this stall thing close to ground in the pattern was important and to pay attention.

Let's get back to AOA indicators. Can AOA indicators help? Yep especially with aural warning. SHOCKING revelations below that will blow your mind.

* Have you ever noticed that AOA videos always seem to be taken in calm winds and straight in?
Ed, a strawman argument. Of course. I've seen +/- 10 kts on airspeed indication on approach in a B767. Airspeed and V/S all over in turbulence, bank and pitch changing and had to fight for control. Do all LOC accidents happen in moderate/severe turbulence? LOC is due to pilots not using the rudder, stick, throttle and their head, to maintain flying speed, attitude and manage risk.

Airliners have AOA vanes on side of aircraft near cockpit but no direct AOA indication. The ADC provides “dynamic” stall speed shown on airspeed tape (red). Airliners are close to stall and high speed buffet simultaneously (coffin corner) in high altitude cruise. Airliners do stall occasionally. The AOA vane angle input goes to Air Data Computer (ADC), which also processes inputs from: pitch/bank/yaw current & rate of change, altitude, airspeed & vertical speed (instantaneous IRS accelerometers), flight control & high lift positions, density altitude, current gross weight in FMS and more. AOA helps predict impending stall trend. Along with EGPW (enhanced ground proximity warning) gadgets save lives.

Garmin or Dynon or other EFIS in our RV’s use differential pressure and software to convert to AOA and EFIS display. Some AOA indicators are analog like an pitot/static airspeed indicator. SHOCKING revaluation, Ed you use AOA in your RV-9A and seem to love it while objecting to AOA. You do bring up a good point (read next).

I have a progressive aural stall warning in my RV-9A and like it. I have a visual AOA on the PFD of the RV-9A and never use it. And as for a glare shield display, that might not be in your primary field of view when you’re not on final, even if it were not for its inherent limitations mentioned above.
Ed you realize your RV-9A has AOA and the aural stall warning is AOA. Every Cessna, Piper has an AOA indicator, a stall warning horn required by Part 23. Of course this AOA indicator (stall warning) has one AOA indication, immanent stall. Cessna and Piper have different "progressive" sounds indicating stall is near. Cessna pilots know stall horn gets louder as you approach stall. The Piper (electric) stall horn tone is intermittent then goes steady closer to stall.

Yes a big bright AOA indicator heads-up on glare shield is in line of sight and way more useful than a tiny dim annunciation on crowded EFIS PFD full of data down low on the instrument panel, which requires you to go heads down. That is why Part 23 requires aural warning. Visual is secondary. It is funny you are using AOA (aural) on your RV-9A while saying you don’t use it. :rolleyes::D The EAA prize winner's innovation was his AOA uses different beeps to indicate critical angle of attack, as well as slip and skid by using differential volume, left to right ear.

14CFR23.207 — Stall warning. (a) There must be a clear and distinctive stall warning, with the flaps and landing gear in any normal position, in straight and turning flight. However, a visual stall warning device that requires the attention of the crew within the cockpit is not acceptable by itself.

AOA or RESERVE LIFT, provides indications before stall WITH both visual and aural warnings of the LIFT/DRAG bucket. COOL! Otherwise it is seat of pants interpreting A/S, V/S, Pitch attitude, Power and view of ground rushing up to smite ye mightily. This is useful and nothing you said has refuted that. The skilled smart PIC is #1 most important safety device in the cockpit. AOA is a tool to assist, like GPS and Autopilot.

Truth be told, airline pilots cheat when landing. Radar altimeters call out height above runway, “minimums, 100, 50, 30, 20, 10.” I landed without it for many years. When transitioned to a plane with it, I was annoyed at first, than loved it. I land without it, but it's far more consistent and easier with RA call outs. SAME WITH AOA. Maneuvers are more consistent and add confidence when pulling G's. AOA is great in dog fighting your buddies.

Really, I think the issue is not technical, it’s psychological. Think back to the fork-tailed doctor killer of the 70s (Beech Bonanza) when those accidents were dysfunctional addressed by the Beech pilots.
Fork tailed Doctor Killer is a meme or cliché. Beech 35 V-tail had flutter aeroelasticity issues before the 70's, going back to first 1947 models. Bonanza 35's are high performance retractable gear planes. In a nose down spiral they accelerate fast exceeding Vne quickly. Weather is a factor, especially in planes which travel great distances. Would an instrument rating and autopilot help? Yep. A standard spiral recovery is something every Pvt pilot on up is taught. Do pilots practice and stay current in upset recovery: 1) level wings with coordinated aileron and rudder and AT SAME TIME throttle to idle, 2) Recover from the dive (no abrupt/full input at high speed). No thinking, muscle memory, from consistent regular training. Pilots don't like seeing a windscreen full of the ground in training. Flight Reviews are missed opportunities.

Mooney aircraft also had/have higher than average accidents. Most models made in the 60's came with PC, positive control, a full time wing leveler (like an autopilot but no Hdg/Nav track). You pressed a button on yoke to disengage PC to maneuver. PC reengaged automatically when you released the momentary action button on yoke. Intent was laudable. Now EAB kit plane builders are lucky. For a small cost you can add on 1 or 2 axis Autopilot to a EFIS. Gadgets can help make safe competent pilots even safer. ADS-B weather in flight? Yep winner.

Anybody who wants to come fly the Expanded Envelope Exercises®....
Registered trade mark? OK. I support anyone who strives to improve pilot proficiency, theirs or others. I appreciate your philosophy of pilots expanding their flight experience, loosen up, feel full control deflections, push their comfort level (safely). Good work! As a CFI 30 yrs, I know CFI's who go beyond Min standard maneuvers, to address individual students needs with creative flight exercise. CFI’s have been using exercises like yours to achieve the goal of precision flying, middle of envelope (where safety is max).

My advice stay current, work towards more ratings, especially Instrument #1. Commercial rating? Yep both these will make you a better pilot.

“A superior pilot uses his superior judgment to avoid situations which requires the use of his superior skill.” Frank Borman
 
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