This is a very good video. I plan to add an AOA system to my next airplane. I went to the Alpha Systems web page and they quote pricing (with $100 discount if you mention this guys video). It looks pretty straightforward. How much do you think the installation would be - say in a typical Cessna product?

soyAnarchisto wrote:This is a very good video. I plan to add an AOA system to my next airplane. I went to the Alpha Systems web page and they quote pricing (with $100 discount if you mention this guys video). It looks pretty straightforward. How much do you think the installation would be - say in a typical Cessna product?

Install 6 to 8 hrs, pretty straight forward, depends how is your panel and glare shield if easy access or not, this is the most time consuming of the install.

Okay, guys, look at the sensors on a TRUE “angle of attack” system. They are always symmetrical…..one on each side.

If you understand aerodynamics, you should know that the angle of attack CAN be different at different points on a wing’s span.

So, these simple systems produce an indication (accurate or not) at one point on the wings span…usually about halfway out one wing. So, your measurement is at about one quarter span. What’s the rest of that wing doing? That’s point 1.

These systems also need to be calibrated. Meaning you set them, then go fly to determine where the device indicates the stall. Then you land, and adjust the sensor to more closely represent the stall. Then fly again. Rinse/Repeat till you’re happy with the indication.

Almost every pilot I’ve flown with, after that much mucking about at high alpha in these small planes can already reliably FEEL the impending stall. So, that’s point two: why spend a bunch of money on a device that just reminds you of something you SHOULD be able to feel anyway?

Point three: my plane has an early Alpha Systems device. It is useless. All I had to do was look at the sensor to figure that out: It’s virtually a duplicate of a Piper Warrior pitot mast, mounted at an angle. This is high science, right?

Point four: AOA systems have most often been installed on aircraft with a LARGE difference between empty weight and loaded. And on heavy aircraft which don’t have the “up close and personal” feel of a Cessna, for example. OR, most commonly, on aircraft you simply DO NOT ever, ever stall (think swept wing jets).

I’m going to remove this POS from my plane some day, but unfortunately it’ll leave hole in the wing and a hole in the glareshield.

But, folks it is NOT a “True Angle Of Attack” instrument, at least in the pure sense.

That’s my opinion, so take it for what it’s worth…

MTV

^^^^^
What he said.

mtv wrote:Okay, guys, look at the sensors on a TRUE “angle of attack” system. They are always symmetrical…..one on each side.

If you understand aerodynamics, you should know that the angle of attack CAN be different at different points on a wing’s span.

So, these simple systems produce an indication (accurate or not) at one point on the wings span…usually about halfway out one wing. So, your measurement is at about one quarter span. What’s the rest of that wing doing? That’s point 1.

These systems also need to be calibrated. Meaning you set them, then go fly to determine where the device indicates the stall. Then you land, and adjust the sensor to more closely represent the stall. Then fly again. Rinse/Repeat till you’re happy with the indication.

Almost every pilot I’ve flown with, after that much mucking about at high alpha in these small planes can already reliably FEEL the impending stall. So, that’s point two: why spend a bunch of money on a device that just reminds you of something you SHOULD be able to feel anyway?

Point three: my plane has an early Alpha Systems device. It is useless. All I had to do was look at the sensor to figure that out: It’s virtually a duplicate of a Piper Warrior pitot mast, mounted at an angle. This is high science, right?

Point four: AOA systems have most often been installed on aircraft with a LARGE difference between empty weight and loaded. And on heavy aircraft which don’t have the “up close and personal” feel of a Cessna, for example. OR, most commonly, on aircraft you simply DO NOT ever, ever stall (think swept wing jets).

I’m going to remove this POS from my plane some day, but unfortunately it’ll leave hole in the wing and a hole in the glareshield.

But, folks it is NOT a “True Angle Of Attack” instrument, at least in the pure sense.

That’s my opinion, so take it for what it’s worth…

MTV

If you fly often and challenging kind of flying, you get used to the feel of the airplane, you dont need an AoA or airspeed indicator or stall warning, but most pilots do not fly often, I think the average is 50 hrs? and many only fly point A to point B, you will never get a feeling of the airplane that way.

For landing and take off you can do by feel if you fly often , but for Vx, Vy, best glide, aerobatics, dogfights, is nice to have an instrument that compensates for the variables and its accurate, a lot better than an airspeed indicator or stall warning at least.
I got my AoA indicator when I had like 100hrs total time and was learning to fly the jungle strips in Costa Rica on my own without a backcountry instructor, the AoA indicator teaches you to fly the wing, that instrument was my instructor, this is why I am total believer in this instrument.

This instrument can save lives, not all pilots are that proficient, or skilled, and anyone can make mistakes, even the best pilots, I will put an AoA indicator in every plane I will ever own, I am aware I am not a perfect pilot, so any help to make me a better and safer pilot is welcomed.

I agree some AoA indicators are useless, I have friends buying older ones or cheaper ones,it was a waste of money.

mtv wrote:Okay, guys, look at the sensors on a TRUE “angle of attack” system. They are always symmetrical…..one on each side.

If you understand aerodynamics, you should know that the angle of attack CAN be different at different points on a wing’s span.

So, these simple systems produce an indication (accurate or not) at one point on the wings span…usually about halfway out one wing. So, your measurement is at about one quarter span. What’s the rest of that wing doing? That’s point 1.

These systems also need to be calibrated. Meaning you set them, then go fly to determine where the device indicates the stall. Then you land, and adjust the sensor to more closely represent the stall. Then fly again. Rinse/Repeat till you’re happy with the indication.

But, folks it is NOT a “True Angle Of Attack” instrument, at least in the pure sense.

Pilots,

You know that most of the instruments mounted in the aircraft are not actually measuring the true values of whatever information they display, and that each have their associated errors and limitations. Furthermore, most need some sort of "calibration" prior to each flight and some periodically during flight to keep them useful.

Airspeed indicator is a pressure gauge.
Alitmeter is a pressure gauge.
Compass is a magnet floating in fluid.
Heading indicator is a gyro and doesn't actually know its true heading.
Attitude indicator is a gyro.
VSI is a pressure gauge.
Turn coordinator is a gyro.

You could apply much of the same arguments presented above for AOA for all of these instruments, just change the name. It is important to understand what you think you are looking at, what the limitations are, as well as the associated errors.

There are some pilots who can hear the wind over the plane and figure out about how fast they are going. They don't need the airspeed indicator. Other pilots can feel the plane across the entire weight and balance envelope. For those who cannot, the AOA indicator may provide one more bit of information that, like the other supplemental instruments in the plane, may help the pilot to better command the ship.

mtv wrote:That’s my opinion, so take it for what it’s worth…MTV

The gospel according to Mike



Sure glad I’m an atheist

Relative wind noise, like airspeed indication and AOA (I assume) doesn't know when the airplane is entering and going deeper into ground effect. The pilot who has control feel, kinetics, the stuff we are to disregard (for safety) IMC, does feel the airplane can fly slower in ground effect and even slower in low ground effect. Paired with what naturally happens when we look outside while moving toward a target, the continued apparent brisk walk rate of closure with that target given deceleration, this feel allows for safe deceleration on short final to touchdown slowly and softly (with power) on the desired spot with some practice. Actually I have demonstrated with zero timers that it takes less practice than does the round out and hold off technique.

When the computer controls airspeed with elevator input and controls glideslope and rate of descent with autothrottles, I assume the long runway is necessary fudge factor. The computer does not touch down slowly and softly on the numbers. As MTV and others say about smaller airplanes with less difference between max and empty weight, man does the better job by his kinetic feel and not by instrumentation. Computers seem to be better with instrumentation.

Patrick Romero and the Carbon Cub guys and the AOA (I think) are using Wolfgang's stall down approach or a very slow power/pitch setting all the way down to the flair and short hold off or bounce.

In the videos, especially later videos, I see both Jughead and Motoadve decelerate on short final. This is human brain power, apparent rate, voodoo, or whatever. They "feel" that slower airspeed is possible coming into ground effect and use that advantage to their advantage.

Backcountry flying, crop dusting, pipeline patrol, or any low altitude professionally done work is not IFR nor is it integrated instrument. To get enough data outside the airplane, that inside stuff has to be (other than heads up and aural) almost completely ignored. It is an attractive nuisance.

Computerization has increased safety IFR and will eventually be able to safely maneuver near the ground. The fully automated auto is having growing pains. Until then, we need to learn to feel. We need our inner ear and brain and optical illusion and all that visual flight stuff.

Larry,

I enjoy watching your videos and I think you have found an optimal way to use the AOA. I do however feel there is an advantage to just learning the airplane by practicing STOL flying and slow flight. I have a sportsman STOL kit and use my stall horn as a cheap man's AOA. I use the start of the horn as great place for pitch attitude on landings. You are right that the ASI is essentially worthless at slow speeds but I have been able to learn the characteristics just through lots of practice and wonder how much it would help me at this point. I think the best advantage of the AOA would be determining best glide. Since there are so many factors that effect this speed it could potentially make the difference in finding suitable terrain for a safe landing where guesstimating in the air without one wouldn't. I am curious if any of the guys competing in Valdez, Alaska use them ?


Josh

I enjoy low & slow as much as anyone else, for me its a "feel" game for which AOA isn't on my need or want list.

Equally where the airplane design eliminates feel or creates artificial feel thru springs and/or hydraulics AOA indication becomes a valuable assets and is very much on my need/want list.

First, I’m not advertising, nor am I being reimbursed for any “opinions” I post here. That’s not a universal truth on the internet.

Second, to respond to motoadve’s Comments:

Good, comprehensive TRAINING in slow flight regimes is what makes pilots better, and safer. I shuddered when I read his description of essentially self teaching himself to operate in confined areas. That is NOT a criticism of him, by the way….it’s more a criticism of the “system” by which we certificate pilots these days.

I too “self taught” a LOT more than I should have needed to. So I sympathize with him for looking for another “tool”.

The tool that I prefer is better instruction, conducted by qualified and motivated CFIs. They’re out there, but the FAA has just eliminated a lot of them from instructing.

Rather than clutter up this thread, I’ll start another on THAT absolutely insane topic.

But, in my opinion, a qualified, well trained pilot should not need one of these devices to operate in confined areas or low level maneuvering flight.

MTV

Just Curious, has anyone used the Uavoinix AV-30 or AV-20 AOA indication? Is it any good, or sketchy?

C150Driver wrote:Just Curious, has anyone used the Uavoinix AV-30 or AV-20 AOA indication? Is it any good, or sketchy?

I think they are close. Mine shows a lot of red when I doing real short and slow work. So I'm not sure it's real accurate in those settings, as the plane is still very solid. I am on MTVs camp with AoA indicators and basically just fly by feel. I have a customer who has one and flies by it. He scared me on an approach because it was so fast, and when I demonstrated one of my approaches for him I could hear the nervousness in his voice when he was calling numbers and reading the AoA.

mtv wrote:Okay, guys, look at the sensors on a TRUE “angle of attack” system. They are always symmetrical…..one on each side.

If you understand aerodynamics, you should know that the angle of attack CAN be different at different points on a wing’s span.

So, these simple systems produce an indication (accurate or not) at one point on the wings span…usually about halfway out one wing. So, your measurement is at about one quarter span. What’s the rest of that wing doing? That’s point 1.

These systems also need to be calibrated. Meaning you set them, then go fly to determine where the device indicates the stall. Then you land, and adjust the sensor to more closely represent the stall. Then fly again. Rinse/Repeat till you’re happy with the indication.

Almost every pilot I’ve flown with, after that much mucking about at high alpha in these small planes can already reliably FEEL the impending stall. So, that’s point two: why spend a bunch of money on a device that just reminds you of something you SHOULD be able to feel anyway?

Point three: my plane has an early Alpha Systems device. It is useless. All I had to do was look at the sensor to figure that out: It’s virtually a duplicate of a Piper Warrior pitot mast, mounted at an angle. This is high science, right?

Point four: AOA systems have most often been installed on aircraft with a LARGE difference between empty weight and loaded. And on heavy aircraft which don’t have the “up close and personal” feel of a Cessna, for example. OR, most commonly, on aircraft you simply DO NOT ever, ever stall (think swept wing jets).

I’m going to remove this POS from my plane some day, but unfortunately it’ll leave hole in the wing and a hole in the glareshield.

But, folks it is NOT a “True Angle Of Attack” instrument, at least in the pure sense.

That’s my opinion, so take it for what it’s worth…

MTV

Couldn’t agree more. Half the Cirrus guys I deal with need a needle to stare at. My eyes are outside and not even glancing at the airspeed on short final.

With that said, I think an AOA indicator could be useful to demonstrate to a new pilot what AOA actually is, and how control inputs affect it. All the stall/spin accidents are due to not fully understanding how AOA works.

Ross

Looking at a big picture,
If every pilot learn to fly with an AoA indicator, they will learn to fly the wing, not an airspeed indicator.
And this will make better pilots and aviation a lot safer.

Yes you need to feel the plane, but that comes with many hrs of flying the plane , training and skill, not every pilot gets the feel of the plane either, I would say most dont, I have flown with lots of pilots in different planes and will say more than half do not feel the plane, they just fly the airspeed indicator and this are pilots with thousands of hrs,
In my case I basically started flying with one since early hrs, the AoA indicator thought me to fly the wing, and get a feel of the airplane all the way to the edge of the envelope.

After flying with AoA indicator for more than 2,500hrs I am confident to say Its the best tool for a pilot who wants to be safe , learn and improve., aren't we pilots always learning?

I’ve always been in the ‘by feel’ camp and still am. However, currently my proficiency is low enough I’ve lost the feel and I’m having trouble getting it back. Perhaps my lost of feel is in part due to some sensory issue. I’ve had a couple bouts of vertigo during low visibility flights and I can no longer go off jumps on my MTB or skis without ending up leaned way right which results in a crash.

In my case I can see an AOA being useful to get the feel back or to act as a crutch to makeup for a sensory issue that blocks being able to fly by feel.

I have been flying with a G3X and it has the AOA and beeps.

Prior to going for my training in Idaho with Dick Williams I was an IAS guy, looking down and then up and so forth on final to nail my air speeds. I was always very slow, around Vso 1.1 as I am always working on being proficient for the backcountry and hitting my spot +/- 50’

All that changed a great deal with the backcountry training. During that 5.5 hour instruction I stopped looking at the IAS and just flew, all of a sudden I could feel the plane. It was such a day of revelations in many ways, I had read and understood the principle of the elevator being responsible for the turn, but on the same day I felt that as well.

As for the AOA, I do like hearing it, but I don’t look at it.

I think I became a much better pilot that day.

Anecdote… three weeks ago we made our first fishing trip venture into the Idaho’s backcountry, I was flying and my buddy who owns the plane (he has not yet had backcountry training so I was flying) started calling out IAS numbers on final into Lower Loon. I was like I’m good I don’t need that.

Eyes out the window, look at my spot, and feel the plane… Pure Joy!!!

But my flying days are over for a year or so, my Kit is likely being delivered the last week of this month and then it is all building when I am not traveling for work.

motoadve wrote:Looking at a big picture,
If every pilot learn to fly with an AoA indicator, they will learn to fly the wing, not an airspeed indicator.
And this will make better pilots and aviation a lot safer.

Yes you need to feel the plane, but that comes with many hrs of flying the plane , training and skill, not every pilot gets the feel of the plane either, I would say most dont, I have flown with lots of pilots in different planes and will say more than half do not feel the plane, they just fly the airspeed indicator and this are pilots with thousands of hrs,
In my case I basically started flying with one since early hrs, the AoA indicator thought me to fly the wing, and get a feel of the airplane all the way to the edge of the envelope.

After flying with AoA indicator for more than 2,500hrs I am confident to say Its the best tool for a pilot who wants to be safe , learn and improve., aren't we pilots always learning?

So, here’s a question for you: EVERY “AOA” device has to be calibrated. So, if you can’t feel what the plane is doing, how did you set up your “AOA” system to read accurately?

The one in my current plane, set up by the previous owner, is not even close to accurate……I fly approaches at solids “actual AOA”, and that device is buried deep in red. And there’s plenty left still. So, apparently the guy who set it up never really flew the plane, because if I used that thing, I’d be hauling ass every time I landed.

An “AOA” device that’s set up by the owner……ummmmm.

MTV

Calibration its pretty easy, fly at the lowest speed where the airplane does not sink or climb, then press the set calibration button and you are done.
Or another method is, stall the airplane see the speed you stalled at, and fly at 1.3 of that speed and press the calibration button at that speed.
I have tried both methods they are really close, I prefer the first method because you are not dealing with ASI inaccuracies.