Airline Pilot Central Forums

Airline Pilot Central Forums (
-   Safety (
-   -   Not understanding AoA indicators... (

cardiomd 11-22-2014 08:04 PM

Thanks Adler for the post. I really don't mean to come across as a jerk and sorry for appearing dismissive. And again for the record I would like to fly in a plane with direct AOA readout as I said, would be fun and heck I always like to get as much experiences in flying as possible.

I'm also not "negative" about AOA. I see the utility, but a few on here had an almost religious fanaticism about it that I usually only see people get when talking about the latest Apple product. ;) If somebody wants/needs it in their craft go right ahead.

I see a lot of disrespect for the skills of the GA pilot which is very confusing to me then I talk or fly with few of them and am positively blown away by the lack of skills or knowledge base often present. There is a wide range of academic and aeronautical ability and physical hand-eye type lacking that is (hopefully) not present in the pro community where everybody is held to recurrent training and higher standards. Again I will have to watch for this in myself (as you guys will too after you retire from pro duties) as we age and we all fly less than we used to. Ego should not enter in to the equation.

The conversation seems to have shifted to AOA as a "training aid" and again that would be potentially useful in GA planes for somebody who perhaps does not really have a good understanding about flying, how lift is generated, induced drag curves, etc.

I still have difficulty seeing the day to day use for the average GA pilot who should not get anywhere near an accelerated stall regime but I do agree it would be interesting and useful in training. I upgraded to glass and feel it has HUGE advantages, and makes IFR simpler, and is a fantastic thing. I don't argue that everybody should do so.

cardiomd 11-22-2014 08:08 PM

BTW if any of you are interested here is a fantastic AVWeb describing another fatal stall/spin in the modern-day doctor killer, Cirrus SR22.

Would an AOA gauge help? Well certainly an understanding of aerodynamics would have avoiding high load high-G maneuvers close to ground resulting in high AOA and a spin when trying to "make" a runway.

cardiomd 11-22-2014 08:28 PM

Originally Posted by Yoda2 (Post 1769217)
I believe the model on Fred Scott's deal featured aural tones and female voice. I think its canned phrases should be expanded to also say things like "Nice landing" "You're an awesome pilot" and "Sorry, you're screwed!"

I would totally get one if it had the Arnold Schwarzenegger expansion pack.

Approaching stall AOA???

Fluglehrer 11-22-2014 10:33 PM


Originally Posted by Timbo (Post 1769205)
I'd like it more if it had an aural tone too! :D

Definitely, especially if it was a graduated tone. The attack jet I flew had a tone capability at high AOA that was very helpful in BFM, but not something you heard much elsewhere, and if you did it was time to figure out why and fix it.

Arnold would be a good choice for the aural:

JamesNoBrakes 11-22-2014 10:59 PM

Originally Posted by cardiomd (Post 1769218)

I still have difficulty seeing the day to day use for the average GA pilot

True. Regulations are made for the lowest common denominator.

Fluglehrer 11-23-2014 12:14 AM

There is a great deal of info out there for anyone who would like to learn more about the usefulness of AOA. Here are a few I like:

Angle of Attack by a pilot named Eddie Haskel. He has a good explanation of the usefulness of an AOA gauge from his personal experience in corporate aviation and as a USAF pilot Everybody Has an Angle (of Attack)
His website is a great source of info.

Another is Noel Kruse’s “Fly Better” books, especially his “Book One, Aerodynamics” (a free download from He is excellent at making important connections, such as: “The angle of attack of the wing is caused by the angle of deflection of the elevator, independent of the airspeed. If we pull the stick back too far and deflect the elevator too far we will increase the angle of attack of the wing beyond the critical angle and stall it.” So even if you don’t have an AOA gauge, you do have a knowledge of what stick position will cause a stall. That stick/yoke position will cause a stall at any attitude and airspeed (well, if you’re fast enough above Va you will break your plane before you are able to pull back far enough to reach a stall).

Here is a NASA study on AOA effectiveness:

JNB and Adlerdriver had a discussion about whether it would be worse to have high AOA in a level or descending turn. I think most military guys would say a descending turn is worse, and Adlerdriver says this is because you not only have to break the stall, you have to stop the sink. JNB, I think you also agree based on this quote of yours, which describes the problem of a descending high AOA turn well: “Again, when they get slow, they can get into a regime where they are not at an excessive pitch attitude, so not stalled or stalling, but where they are sinking and the AOA is way high due to the combination of slow speed, induced drag, etc.”
The T-38 had a large number of fatal final turn stalls, and the addition of the AOA gauge and especially the “AOA Indexer” at the top of the glare shield was intended to help stop this. Most of these accidents were high sink rate mishaps with high AOA. After the addition of AOA the USAF increased the speed of no-flap approaches and probably (my surmise based on memery from talking to graybeards when I was young) changed their way of flying final turns from tight, high sink rate, high AOA (probably .7 to .8) final turns to a more relaxed .6 AOA turn. Here is the study that put AOA into the T-38:,d.cGE

I do remember my first night flight with another T-38 instructor as I was a 2nd Lt. Instead of an overhead he flew more of a sliceback to the runway, with .8 or higher AOA the whole turn and stroking burners during the rollout to final to kill the sink rate (VSI was pegged at 6000 fpm plus). Kept me awake.:eek:

Not sure if anyone already posted this link to the FAA recommendation for AOA:

Timbo 11-23-2014 04:10 AM

Originally Posted by Yoda2 (Post 1769217)
I believe the model on Fred Scott's deal featured aural tones and female voice. I think its canned phrases should be expanded to also say things like "Nice landing" "You're an awesome pilot" and "Sorry, you're screwed!"

And it should also say something on final, to keep you awake, something like,

"Is your wife home? Yes? We could go to a motel..."

Just a little incentive to make a better landing! :D

The MD88 does have a b!tching Betty voice that says all kinds of things like; Flllaaps, and Overpseed. And the Airbuses will call you a Retard, twice!

The 777 has an AOA indication in the upper right corner of the ADI but it's small and we were never taught to use it properly. The airplane has other low speed warnings before you get into the red on the AOA, right on the airspeed tape and will yell "Stall Stall" at you too. Still, the Asiana guys managed to get way behind the power curve on a clear day in SFO.:rolleyes:

rickair7777 11-23-2014 07:06 AM

Originally Posted by USMCFLYR (Post 1765011)
You didn't read a single link I suggested or any of the series of posts by Fred Scott did you?

If you had - then you would heard what most of the GA pilots were saying about the utility of the AoA instruments currently available at a relatively low cost to the GA community. You don't have to have "grown up with it" to appreciate the benefits. That is a gross overstatement to the training required to effectively utilize it. We're not asking the recreational pilot to use it to the extent, or for the purposes, that the fighter pilots used it on a routine basis.

Btw - I was flying before the military so I wasn't initially trained AT ALL on its use or benefits. It wasn't until T-34C training that I was introduced to it and I could still see the benefits of such information. When I got back into civilian (professional) flying did I find to my surprise that the turbine equipment I was then training on did not have any AoA information available.

Of course I read it. I have no problem at all with people using it if they want to, assuming they are savvy enough to learn how and develop the right habits. Some rich guys who just buy the latest techie fad for their airplanes, thinking that money buys safety margin, are more likely to just get distracted by an AoA or mis-use it.

But if this is going to be the next great leap in GA safety, as some folks advocate, then it will need to be incorporated into early training.

I'm not giving you grief on this; it was jetjoc who was a bit caustic.

rickair7777 11-23-2014 07:27 AM

Originally Posted by Cubdriver (Post 1768746)
I think a large scale shift in flight training over to using AoA concepts would be appropriate.

I agree, it would be good. But it's a big, big step...the FAA would have to mandate this, adjust FAR 61, and educate the CFI population.

Then primary trainers would all need AoA gauges...along with their ADS-B out.

None of the big flight schools are going to do it unless it's would drive their costs above their competitors in the short term.

I'm not sure I can envision a practical roadmap to get there...AOPA and the FAA (and maybe the NBAA) would have to agree, and the RAA would fight it tooth-and-nail since it would increase the cost of fresh seat-meat ever so slightly, and would impact their training programs.

Yoda2 11-23-2014 08:31 AM

When I started this thread I wasn't sure what to expect; probably some yes, no or maybe so's... Instead it has turned into a great and fruitful conversation and thank you everyone, even Cardio! Anything new, or new to a person, often gets met with resistance, skepticism and misunderstanding. It's natural and generally a good thing; part of the vetting process. It would be interesting to put Orville and Wilbur in the cockpit of a modern jetliner or even a well equipped GA aircraft. I'm not sure if they would be full of amazement, wonder and approval, or their heads would explode!

All times are GMT -8. The time now is 11:35 AM.

User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2022 DragonByte Technologies Ltd.
Website Copyright ©2000 - 2017 MH Sub I, LLC dba Internet Brands