The FAA recommends owners of all airplanes install and calibrate an Angle of Attack (AOA) alerting system and receive training on its use.
“Increasing awareness of the benefits of these alerting systems may reduce the risk for loss-of-control (LOC) incidents and accidents,” is noted in the introduction of Special Airworthiness Information Bulletin (SAIB) 2024-07 — STALL WARNING SYSTEM, Angle of Attack Alerting Systems — issued on Dec. 26, 2024.
The bulletin references the 2009 Colgan Air crash (Flight 3407) and its NTSB investigation, which highlighted the risks of improper stall recovery and insufficient low-airspeed alerting.
The NTSB recommended the FAA require installation of such a system for all airplanes operating under Part 121, 135, and 91, subpart K.
The SAIB also summarizes the benefits and limitations of such a system, including:
AOA Benefits
- Offers a more reliable indication of an impending stall than airspeed indicators alone.
- Audible alerts improve pilot awareness before a stall occurs.
- Indicators assist pilots in stall prevention, unusual attitude recovery, and energy management.
AOA Limitations
- Pilots must be trained to use AOA indicators effectively.
- Variations in AOA display types present standardization and training challenges.
- Proper installation and calibration are essential to ensure accuracy.
SAIBs are informative, not mandatory.
I really wanted to sit this one out, since it’s another topic where the discussion always tends to go sideways. But…
I guess I missed the “FAA requires…” part that triggered a lot of these comments. I can only find:
“The FAA recommends owners of all airplanes install and calibrate an Angle of Attack (AOA) alerting system….”
That’s too bad, though…maybe they should require them.
I learned to fly in an antique Cessna 150. Immediately following my Private checkride (which I, um, failed the first time), I started flying taildraggers, starting with a 7-ECA Citabria, then a PA-12 Super Cruiser, a PA-25 Pawnee, Cessna 140, J-3 Cub, 7-AC Champ, Cessna 170B, PA-18 …and a ‘new’ 7-GCBC.
All of which required me to rely on my basic stick & rudder skills, plus maybe a little ‘Kentucky windage’…
Interspersed in that string were a bunch of hours instructing in PA-28-140s & PA-28R-200s…which had “modern” avionics, like a KX-170B & ADF.
Then, I got lucky enough to fly several extremely high-performance aircraft where being “On Speed” referred to an angle of attack…not an airspeed…with the AOA indicators prominently displayed in my field of view.
They weren’t installed because of an “FAA requirement”, but I was glad to have them.
As mentioned earlier; an AOA indicator is “just another tool”.
Will an AOA indicator keep you from groundlooping your Cessna 185, or help you make better wheel landings? Probably not.
But how many folks remember that published “V-speeds”, like Vs, Vx, Vy, Vg, Va, Cessna’s OCS, etc., are based on either your max gross weight, or ‘As Noted’ in some cases.
If you’re at a different weight (hopefully lighter), and you’re still using the published speeds, you’re robbing yourself of better performance, unless you do the math to figure out the actual speed…even if it is only a couple knots difference.
OTOH, an AOA indicator will always show you how much more (‘reserve’) lift you’ve got available, at whatever precise airspeed you’re flying.
That can be a pretty useful tool when you’re trying to crawl out of that “hole”.
Respectfully: Don’t knock them if you haven’t tried them.
The best aeroplane to learn to fly is a Citabria ECA. By far.
No flaps, a tailwheel, low power and minimum of instruments.
Microsoft Flight Simulator and other so called computer based simulators, have made folk think flying is looking solely at instruments.
Attitude flying is all about looking outside.
What a great disservice glass panels have done to primary training.
Nailed it, but any “old“ taildragger will work to teach a person hpw to be a real pilot!
taildraggers and gliders together will teach you many stick and rudder skills for you to becoming a competent pilot.
Back when I was learning to fly, with an awesome instructor, it was drilled into me…”FLY THE AIRPLANE!” Of course this was followed up with “get your eyes out of the cockpit”. Several other concepts were ingrained in me by my instructor. Among those were, as someone already said, Attitude and Power. My instructor taught it this way, Pitch (aoa) and Power. We practiced slow flight so often that I came to really enjoy it! Knowing how the airplane felt, how it moved, what the wind was like, knowing how to stay just out of the stall horn, made me a better pilot. I did some time in a glider as well…great lessons to learn there.
Oh, and on another note, it’s just not rocket science; unless you’re thoroughly trained to, with mil experience or flying big iron, don’t fly in bad weather! How hard is that? I’m amazed, and saddened, by the tragic decisions many accident pilots make. Who taught them to fly? Aviate, Navigate, Communicate.
Alpha (AOA) and Beta (Yaw) are both helpful, perhaps even insightful, but neither parameter is necessary to maintain aircraft control.
I think I will quote General Yeager “If you don’t know what your AOA is you should not be flying”. FLY NAVY!!!
Alpha & Beta would be even better. Yeager was Air Force. 🙂
All one needs these days to “pilot” an aircraft is to be trained like a performing organ grinder’s monkey to be a pilot. These days, reliance on gadgets & gismos takes precedence over basic staying-alive skills. I was fortunate enough to be taught by ex-WW2 pilots who survived in combat without any of the modern gadgets etc – they weren’t around 65+ years ago. A return to learning to fly without all the EFB gadgets & “glass cockpits” would go a good way to ingraining basic skills that kept those ex-WW2 pilots (& me – 65+years of flying & still currently flying). Learning to fly on just the basic instruments as found in Tigermoths & PA18’s would be a good grounding for all would-be pilots. Paul.
It’s nice to pine about the better ways “we used to do it” but you do know that in the 40s, we killed more pilots in training than in combat, right? And that in every decade since then we kill more pilots through stall/spin accidents than almost all other causes, right?
Nostalgia doesn’t make “the good ol’e ways” better.
forgot this … good thing i don’t have to remember to put down the landing gear anymore.
https://www.ntsb.gov/safety/safety-recs/RecLetters/A-10-010-034.pdf
an AOA would not have made any difference. wasn’t this the accident that made 1,500 hours the minimum for an ATP again … here in the states ?
seems my initial comment didn’t get approved. the short version.
from page 1
The National Transportation Safety Board (NTSB) determined that the probable cause of
this accident was the captain‘s inappropriate response to the activation of the stick shaker, which
led to an aerodynamic stall from which the airplane did not recover. Contributing to the accident
were (1) the flight crew‘s failure to monitor airspeed in relation to the rising position of the
low-speed cue,3 (2) the flight crew‘s failure to adhere to sterile cockpit procedures, (3) the
captain‘s failure to effectively manage the flight, and (4) Colgan Air‘s inadequate procedures for
airspeed selection and management during approaches in icing conditions.
From the 1st page ( do i need a stick shaker for my RV-3 ? )
The National Transportation Safety Board (NTSB) determined that the probable cause of
this accident was the captain‘s inappropriate response to the activation of the stick shaker, which
led to an aerodynamic stall from which the airplane did not recover. Contributing to the accident
were (1) the flight crew‘s failure to monitor airspeed in relation to the rising position of the
low-speed cue,3 (2) the flight crew‘s failure to adhere to sterile cockpit procedures, (3) the
captain‘s failure to effectively manage the flight, and (4) Colgan Air‘s inadequate procedures for
airspeed selection and management during approaches in icing conditions.
As a FAA Master Pilot and CFI/CFII I’ve flown over 25 different aircraft, only 1 had an AOA, a newish C172. It was distracting and I found it useless at best. Where I concede a AOA might be useful during a carrier trap at night, in a C172 on a 4000 ft runway? Really? I guess that with the European airlines approach of airplane management vs pilotage it could be useful as a crutch for poor piloting skills.
Head out of the cockpit, feel the airplane, hear the airplane, fly the airplane!
And as a requirement for ALL planes it’s just a classic FAA bureaucratic nonsense solution that won’t work. Hey, this might save someone’s life, let’s make it mandatory for everyone!
BTW, in my aerobic Skybolt would I be required to have 2? A second one for inverted flight?
Right on, Larry!
Kit:
I kind of felt the same way. Spent my life flying airspeed, from soloing in a Cessna 172 in 1968 to left seat on the 747-400, across a range of airplane types through the years. Still fly a T-6 (when I can pry my daughter’s hands off of it). But this lack of AoA direct experience was corrected when I flew a Pilatus PC-12 in retirement, and forced myself to shift from airspeed to “the donut.” It took maybe 100 hours to transition my attention from airspeed-first, angle of attack-second, to the other way around where it’s AoA first, most, and primary (and oh-yeah-IAS-is-about-right-too but who-cares).
AoA was a spectacular improvement in wing awareness. On landing on big runways, smooth weather: the chance to practice my scan and integration of the information. On short dirt runways in gusty winds? That’s where it paid off knowing exactly how the wing would react — exactly react — when in the flare, regardless of the CG and whatever gross weight. Taking off from a mountain airport, hot and high? Rotate and pitch to the Vx-best angle AoA and nail it for a high confidence, maximum tree top clearance takeoff. Turbulence on takeoff or landing? When the AoA bounced, you track AoA so the bottom of the bounce is the AoA you need — not perfect, but I always had a better idea of what the wing was capable of providing.
I should note the Pilatus wing has a Biblically wicked stall so putting on AoA may have been a negotiated requirement for certification. (YouTube search “Pilatus Stall” and watch the flight test video. FUN STUFF.)
I’m not flying that PC-12 — it was sold so I retired a second time — but you and I had a lot in common and I was won over by actual flight experience.
The only reason I’d put an AoA in an airplane like a Cessna 172 Skyhawk was to teach students to incorporate “the wing” into their panel scanning. And yes, I still think of AoA not as Angle of Attack but “What’s the wing really doing right now?”
Regards, Mark Hilsen in Seattle, Washington
It’s distracting for you because you haven’t been trained in its use, appropriately. My first jet was a Learjet 24/25. You used the AOA for all phases of flight. And I was shocked how Boeings and Airbus aircraft do not have such an indicator. It’s crashes like Asiana in SFO that would’ve ended differently if pilots had an AOA.
The one phrase you hardly ever hear in military flight training is “stall speed”. You are taught from day one there is a stall AOA, and it can be exceeded regardless of pitch or bank angle or airspeed. You do not hear about stall speed increasing with bank angle other naive/simplistic and technically incorrect concepts. AOA understanding is drilled in from day one. That knowledge is coupled with real AOA indicators that actually measure AOA, not derive it from GPS data and display the data prominently within the line of sight (Heads Up) of the pilot.
There is no need to reinvent the wheel. Simply plagiarize what the military has done since the 1950s.
The people commenting know how to fly! It’s the poor quality of instruction that is the real problem. If everyone learned in a glider first would fix most of the problem’s. See pitch and power is airspeed. But with a glider there isn’t an engine so the only thing to do is push the stick forward to keep flying. When I teach you get no instruments! Not a one, you learn to feel the plane. Already saved two pilots who lost their airspeed indicators, no big deal. Pitch and power is airspeed! Your only as good as your instructor, unless you think outside the box and practice!
Glider pilots always say this and it absolutely makes no sense at all. Should all boat captains start with a sailboat too?
Gliders are unsafe. If you knew the statistics, the accident rate is much higher than riding motorcycles.
Also, a motorized airplane does not use pitch for airspeed. It uses power for airspeed and pitch for altitude, unless there is a fixed power setting.
Unfortunately, many GA pilots are taught to fly their powered aircraft like a glider, which is wrong.
Why not just require all aircraft to be filled with concrete? That would solve the problem wouldn’t it? After all, that’s what they’re actually doing, just slowly. Small aircraft don’t have unlimited capacity. Dumb asses (techno geeks that can’t fly ) keep “requiring” magic gizmos to “fly” an airplane for “pilots” that haven’t been trained. More stupidity from the “smart people”.
Next we’ll need three of them so they can vote on which pair is correct like Boeing.
Attitude,Power,Trim
Didn’t the NTSB recently say they were basically ineffective in reducing accidents?
Problem is, they do not teach people to fly the airplane anymore. They only teach to drive the airplane according to all the installed crutches. If you where really interested in safety ect. you would strip “ALL” of the instrumentation and radios out of the primary trainer, and go out and learn to fly the”AIRPLANE” .
Absolutely 100% AGREE!!!
Another tool, YES.
Required, NO.
It’s about time! Military aircraft have been using AOA for 60+ years and I’ve always wondered why it took the civilian community so long to figure it out. I flew backseat F-4 and during landings we used the AOA tone to fly the aircraft all the way to touchdown. With proper training, AOA can be a game changer.
How long have production aircraft had Stall warning devices, which is in fact an AOA device? An analog readout of reserve lift would be nice on GA aircraft, but a requirement? I really question whether it would help when a pilot paints himself into a corner and runs out of options. Stall/spin accidents are not created from rational thought processes, but a panicked response to the aircraft doing something the pilot doesn’t understand. They already ignore the stall warning device, so what makes the FAA think they would pay attention to an AOA device in the same situation?
You make a good point I learned to fly when spin training was the norm not the exception.
Seems they can benefit from remove distractions and fly the plane.
This new digital age has added many wonderful visual awareness devices in the cockpit but IN seems to be where we loose our ability to fly the plane with basic skills and insight of visualizing our situation. Flying around in slow-flight flaps out with the stall warning blaring is good practice for new pilots you really need to pay-attention to the details and how does this feel. Not fun at first but you really learn what the attitude of the plane is like.
More like another incompetence bandaid.
Short of flying out of a hole as a result of an emergency landing, I’ve not in 48 years seen where an AOA would be a benefit.
I remember someone telling me they failed the checkride because they followed the AOA instead of the glidelope for an ILS…
Don’t expect any reductions in accidents. I have about 5500 flying hours, over 3500 WITH Angle of Attack Indicators. Stall spin accidents typically occur during stressful situations when the pilot will not see, hear, or recognize a stall warning (I purposely allowed a warning horn to blare for 30 seconds before my crewmember noticed it).
If we want to get serious about AOA, maybe we should teach what pilot action controls it, and teach to not pull so far back on the yoke.