Angle of Attack Gauge/Meter

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LJS1993

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LJ Savala
Okay guys don't chastize me if this is a dumb question but I'm trying to famliarize myself with aircraft in general and the issues that lead to many accidents. From what I've read a major issue is the stall/spin at low speeds while in pattern or on approach. Now I'm a very new to aviation concepts/techniques/terminology, but if the angle of attack is too radical/extreme then wouldn't a simple gauge noting this in every aircraft eliminate many of the issues with low speed/stall/spin? Again, I'm new and have a lot to learn but could you guys give me some input on this?
 
One would think so.

But, it may be that those that stall / spin wouldn't notice an AOA meter reading any more than they notice existing stall horns, buffet, etc.
 
I reckon an AoA meter is usually only in jets and stuff. I think in a 172 you're gonna know when you're about to stall pretty quickly.
 
It's some thing I've advocated for years, but not something in which the FAA seems interested. However, the option to install a pseudo-AOA gauge in your light plane has been available for a long time -- and at a reasonable price.
http://www.liftreserve.com/
 
LJS1993 said:
Okay guys don't chastize me if this is a dumb question but I'm trying to famliarize myself with aircraft in general and the issues that lead to many accidents. From what I've read a major issue is the stall/spin at low speeds while in pattern or on approach. Now I'm a very new to aviation concepts/techniques/terminology, but if the angle of attack is too radical/extreme then wouldn't a simple gauge noting this in every aircraft eliminate many of the issues with low speed/stall/spin? Again, I'm new and have a lot to learn but could you guys give me some input on this?
Click to expand...

An angle of attack meter is an EXCELLENT device for just this purpose... and they exist for GA planes... The reason they are excellent is that a wing stalls at a given angle of attack. Always. Period. When that critical angle of attack is exceeded, flow is disrupted.. voila.

Now.. why are they mostly in jets and big planes? its mainly because of the weights involved. There can be a difference between gross and empty weights in jets that are in the tens.. or hundreds... of thousands of pounds.. (think - fuel.. cargo.. weapons.. etc). The stall speed in a big jet at gross is SIGNIFICANTLY different than the stall speed at minimum fuel, so those guys train to fly AOA (or calculate the stall and approach speeds for a given configuration, or both). And while the speeds may vary greatly, the AOA's involved do not.

You could do the same for your cessna, piper, etc and work the math out but there would be very little difference between gross and empty stall weights (and speeds) at the level of play we are at in small GA planes.
 
The weight of AOA systems is coming down drastically. I have one in my Tango, but no stall warning/horn.

(Disclosure: My Tango is experimental, which allows me to do cool stuff like install an AOA indicator.)
 
Angle-of-attack indicators have been around for decades. It took awhile, but the FAA is now on board with the installation of an AOA and a simple signoff by the mechanic who does the install.

Bob Gardner
 
LJS1993 said:
Okay guys don't chastize me if this is a dumb question but I'm trying to famliarize myself with aircraft in general and the issues that lead to many accidents. From what I've read a major issue is the stall/spin at low speeds while in pattern or on approach. Now I'm a very new to aviation concepts/techniques/terminology, but if the angle of attack is too radical/extreme then wouldn't a simple gauge noting this in every aircraft eliminate many of the issues with low speed/stall/spin? Again, I'm new and have a lot to learn but could you guys give me some input on this?
Click to expand...

As everyone noted, AoA indicators could be installed in GA aircraft w/o much problem.

I don't think the primary cause of stall/spin accidents in the pattern is lack of instrumentation. The ASI works perfectly to keep a pilot from stalling in the pattern. Inattention in the pattern is what causes those accidents. A pilot who won't pay attention to the ASI will likely not pay attention to an AoA meter.
 
I don't think an AOA Meter would help much either. It would be great for getting maximum performance from the aircraft. However nearly all aircraft are already equipped with an AOA indicator known as a Stall Warning. If a buzzer, horn or light is not going to get a pilots attention then a AOA Meter is certainly not going to.

Brian
CFIIG/ASEL
 
HerrGruyere said:
I reckon an AoA meter is usually only in jets and stuff. I think in a 172 you're gonna know when you're about to stall pretty quickly.
Click to expand...

The CTLS I used to fly has an AOA gauge. I think it is standard equipment. The stall/spin is not going to reduced by instrumentation. IMO. It is reduced by awareness of what causes it and training in how to properly fly an airplane.
 
brcase said:
I don't think an AOA Meter would help much either. It would be great for getting maximum performance from the aircraft. However nearly all aircraft are already equipped with an AOA indicator known as a Stall Warning. If a buzzer, horn or light is not going to get a pilots attention then a AOA Meter is certainly not going to.

Brian
CFIIG/ASEL
Click to expand...

Typically but the time a stall warning comes on and gets the pilot's attention it's already too late. The AoA indicator allows you to determine that your AoA is suboptimal and/or headed in that direction long before the stall warning goes off. I've been flying with AoA in my Baron for several years and I feel "naked" without it. And the latest versions have verbal announcements piped into your headset that are far better attention getter than a buzzer or light.
 
brcase said:
I don't think an AOA Meter would help much either. It would be great for getting maximum performance from the aircraft. However nearly all aircraft are already equipped with an AOA indicator known as a Stall Warning. If a buzzer, horn or light is not going to get a pilots attention then a AOA Meter is certainly not going to.
Click to expand...
If the only issue was stall speed, I'd agree. However, an AOA gauge also gives you best approach, best glide, best rate/angle of climb, best range, best endurance, etc -- regardless of weight/altitude. Only way to get those otherwise is with a POH and a calculator.
 
They would be very good to have, and I think prevent a number of stall/spin accidents if used properly.

I was talking with the owner of a Lancair IV-P a few weeks ago who had one installed in his plane. He's a former U-2 pilot, being able to fly wasn't his issue. He did a full stall in the plane intentionally, it dropped a wing hard, and he said "So after that I installed an AoA meter, and now I just don't stall it. Much better."
 
Ron Levy said:
It's some thing I've advocated for years, but not something in which the FAA seems interested. However, the option to install a pseudo-AOA gauge in your light plane has been available for a long time -- and at a reasonable price.
http://www.liftreserve.com/
Click to expand...
Alpha systems has a similar system with greatly expanded options. The owner is a pilot and has invested a huge amount of time and money in his products. He also recently received a letter from the FAA stating unequivocably that the installation of his systems in a GA airplane is a minor modification requiring nothing more than an A&P's approval/signature.

http://www.alphaaoa.com
 
Ron Levy said:
If the only issue was stall speed, I'd agree. However, an AOA gauge also gives you best approach, best glide, best rate/angle of climb, best range, best endurance, etc -- regardless of weight/altitude. Only way to get those otherwise is with a POH and a calculator.
Click to expand...

Exactly hence my statement "great for getting maximum performance from the aircraft."

But if a pilot is ignoring the airspeed indicator and stall warning then they will be ignoring and AOA indicator as well. So I doubt AOA indicators will do much more to prevent stall spin accidents. It might helps with performance accidents.

Brian
 
Mine is at eye level not buried off to the lower left like the airspeed indicator, so it is a good early warning that one is heading to territory that I choose not to go.

Just another tool, assuming that one is ignoring the speed and stall warning misses the point in my view, the intent is to not get near that edge. AOA helps that.

Ymmmv :)
 
brcase said:
Exactly hence my statement "great for getting maximum performance from the aircraft."

But if a pilot is ignoring the airspeed indicator and stall warning then they will be ignoring and AOA indicator as well. So I doubt AOA indicators will do much more to prevent stall spin accidents. It might helps with performance accidents.

Brian
Click to expand...

I disagree. I believe that many stall/spin accidents happen in loaded situations where the pilot thinks he has sufficient airspeed because he's learned (wrongly) that stall is an airspeed number. In essence, his practice of stalls in level flight have taught him this concept more strongly than the ground school lessons have taught him that load factor/bank angle raise that speed significantly.

An AOA indicator with proper training will give a more consistent message and result, in my opinion.
 
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