Grumman Mallard accelerated stall

[MHemperly]

1 hour ago, DonMuncy said:

My naval aviator friend tells me when carrier landing, they worry about being "on speed" as well as lined up properly. And on speed is  not an airspeed, but an AOA indication.

By the way Alain B, you must learn that when someone likes something in a plane, it is an instrument, but if you want to show your disdain, or put it down, you call it a gadget or toy.

Excuse me... "AOA Instruments" I did say they are cool... 

[Bob_Belville]

While AOA might save your butt in a slow bank, I agree with Don Kaye that what they're best at is allowing a slower speed on final. The AOA indicator, unlike the ASI, is consistent is showing the margin above stall at any weight. When you're light you have to reduce airspeed and estimate 1.2 x Vso. 

[Guest]

No matter if you use ASI or AOA or something else, one sure way to avoid death is to avoid steep turns and coordinated maneuvers close to the ground. 

Clarence

[Alain B]

8 hours ago, MHemperly said:

Sounds like you speak from experience? I have no clue. Enlighten me...   No matter what I still don't think they take the place of the fundamentals of flight, even for an advanced Navy pilot. 

The fundamentals of flight is angle of attack , not airspeed .

[Danb]

Bob at least you now know you can rip that gadget out then go practice your stick and rudder skills, your 30+ years of flying aren't quite enough. 

[Bob_Belville]

15 minutes ago, Danb said:

Bob at least you now know you can rip that gadget out then go practice your stick and rudder skills, your 30+ years of flying aren't quite enough. 

Dan, sarcasm(?) aside, I confess I rarely look at the AOA. But I think I'd pay it more attention if I was going into a 1500' strip.

[Browncbr1]

AOa or not, this guy was hot doggin it and obviously not attuned to, or respectful of the limits of the aircraft.   He just wasn't being safe, and if an audible AOA is needed to keep pilots safe, then there is no such thing as a safe pilot IMHO

[Danb]

32 minutes ago, Bob_Belville said:

Dan, sarcasm(?) aside, I confess I rarely look at the AOA. But I think I'd pay it more attention if I was going into a 1500' strip.

You know me better than that. I use mine quite a bit on my approachs, not much in other areas.

[PTK]

On 1/28/2017 at 11:00 PM, DonMuncy said:

My naval aviator friend tells me when carrier landing, they worry about being "on speed" as well as lined up properly. And on speed is  not an airspeed, but an AOA indication.

By the way Alain B, you must learn that when someone likes something in a plane, it is an instrument, but if you want to show your disdain, or put it down, you call it a gadget or toy.

A fighter jet operating off of an aircraft carrier can have a weight differential of almost 20000 lbs from takeoff to landing using round numbers.

My little Mooney on the other hand has maybe an 800 lbs difference and that's at the extreme high end. 

Hardly a comparison!

The jet lands with assistance on about a 300 foot runway with its AOA ind.

My Mooney lands in about 1300 feet from td to turn off with its ASI. 

I'd say that's not too shabby for my little Mooney!

[201er]

1 hour ago, M20Doc said:

No matter if you use ASI or AOA or something else, one sure way to avoid death is to avoid steep turns and coordinated maneuvers close to the ground. 

Clarence

Wrong. Plenty of people perish on straight ahead takeoffs and go arounds. Why? Because they exceeded the critical angle of attack.

ASI does not provide any angle of attack information. It can be interpreted into angle of attack but requires input from factors like weight, bank angle, etc. This is why many pilots foolishly come up with rules of thumb that are supposed to keep them out of trouble in most circumstances at broad speed ranges, until they don't.

Just because it is possible to navigate with VORs or an ADF doesn't make a GPS, "just a gadget." It is silly and in fact an unsafe attitude to refuse available useful information. Certainly we can't afford EVERY safety enhancement on the planet and our w&b wouldn't allow it so we have to prioritize.

Many of us have realized that stalls are one of the leading causes of fatal accidents, so a "gadget" that aids the pilot's situational awareness to prevent or reduce the likelihood of stalls is a logical priority. But even if it does not increase safety, like an efb or gps an AOA indicator greatly simplifies flying and makes it smother and more enjoyable.

However, an AOAi can increase safety. Not because it is a stall warning or cause it will get you out of trouble. I would say in the moment of the accident, you're pretty screwed either way. However, by flying with an AOAi and becoming aware and experienced at this sort of consistent flying by reference to AOA and not airspeed, the pilot develops better/safer airmanship. You develop a "knack" or "gut feeling" that today at this configuration and these conditions, the nose ought to be pitched this much when you bank that much. And you know what? It works. Just like in the long run you learn how much rudder to put in for how much bank or what pitch attitude under the circumstances will get you what speed. It's just that all your high angle of attack (slow) maneuvers are directly in reference to AOA rather than indirectly through airspeed and some ballparking based on tables or rules of thumb. The pilot with an AOAi has the opportunity to learn the intuitive stick (& rudder but really just stick) skills that even in the absence of the indication are more accurate than when learned on an airspeed indicator for reference.

[aviatoreb]

One thing about AOA indicators to maximize its utility.  I initially had one installed about 5(?) years ago.  It is an alpha systems and I got the one with voice annunciation which I like a lot.  But the indicator was mounted into a free hole in the panel next to ASI. This was good but not ideal because when you want it most, during that last minute of flight, your eyes need to be mostly outside the cockpit and looking down the runway.  So moving the eyes in and out of the airplane and readjusting the focal plane is not ideal.

So about two years ago I had the round lights indicator replaced with a different annunciator, the flat lights bar to have it mounted on the glare shield, down at the front of the glare shield right by the wind screen.  This way it is right in my line of sight during those last minutes of flight and most useful and easy to use.

[Danb]

Erik, I had mine installed on the glare shield just left of the compass, directly  in my line of sight. I hated messing up the glare shield but as you mentioned it needs to be in our line of sight.

[MHemperly]

Geez... the gadget comment seems to have offended some... my apologies! Seriously! 

Didnt think I needed to be so politically correct. I was simply speaking my opinion. Not putting it down or anyone else for that matter. 

Either way, it's unfortunate this guy paid big for his hot dogging. He was low, slow and made a big mistake. Let's spread the word so it doesn't happen as much anymore!! 

Mike

Edited January 29, 2017 by MHemperly

[Cyril Gibb]

It's always amusing to read these AOA vs. ASI threads.  Both opinions are absolutely correct.  AOA gives precise information to maximise performance approaching critical angle of attack to avoid stall/spin.  Using a "cushion" of additional ASI and minimising bank angle will also avoid stall/spin.

I'm of the second variety.  If the density altitude is high and I'm heavily loaded, I won't go to or from a short strip.  If I screw up an approach enough to need a steep bank I go around.  If I'm at all concerned, I carry extra speed.  It doesn't matter to me to float an extra few hundred feet.  I have nothing to prove to myself or anyone else.

However back to the thread.  In my opinion, this crash was simply a result of bone-headed "look at me" buzzing boats and shoreline a few hundred feet off the ground.  No lessons to be learned here other than don't be stupid.   ... let the flames begin

 

[DonMuncy]

4 hours ago, MHemperly said:

Geez... the gadget comment seems to have offended some... my apologies! Seriously.

 

No offense from my side. More amusement, as I have noted the terminology long before you posted. And in far more instances than AOAs.

[M20F]

99.9% of NTSB reports I read are people doing things I scratch my head at.  I have over the years had friends crash and die, great pilots who did things I scratch my head at that result in their death. 

I think what most miss is it isn't lack of AOA, stall horn, or a lot of other stuff.  It is just a momentary lapse of reason in most cases that leads to an unfortunate incident. 

They are called accidents for a reason, don't succumb to the notion of invulnerability. 

[MyNameIsNobody]

I feel badly for the 30 year old woman that chose to "ride along".  I doubt she signed up for "that".  The pilot?  Not so much.  Stupid tricks often have stupid results.  Solution?  Don't do stupid tricks.  I have a Beechcraft pilot that FREQUENTLY does accelerated climb and steep bank at D25.  I have seen him bounce three times on landing.  I anticipate this type of result some time with his repeated stupid tricks.  I won't feel "sorry" in any way shape or form if/when a smoking crater announces the end of one of his tricks...

[Bennett]

My AOA indicator (CYA-100) is mounted alongside my vertical compass where it is easily in sight. My green light is a top, red light at the bottom. I am thinking about changing this to red on top at my next annual. I find it helpful on takeoff as well as landing.



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[201er]

2 minutes ago, Bennett said:

My AOA indicator (CYA-100) is mounted alongside my vertical compass where it is easily in sight. My green light is a top, red light at the bottom. I am thinking about changing this to red on top at my next annual. I find it helpful on takeoff as well as landing.

That may be a logical move. If you want to be more "red" (slow down), pitch up toward the red. If you want to be more green (faster), pitch down toward the green. That way the light indicates in the direction of the pitch and shows an increase or decrease in AOA more directly.

I was just discussing the other day with someone how flying by AOAi is kind of like using a slip/skid indicator ball. On approach (or given phase of flight), you have a target AOA. You set your pitch to try to maintain that AOA, but if it goes off from the target, all you do is make a small pitch correction that brings the ball back on target. If you can keep the AOA "on the ball," no matter how steep you turn, you are safe and can't stall. Doesn't work like that with airspeed.

[Bob_Belville]

9 minutes ago, Bennett said:

My AOA indicator (CYA-100) is mounted alongside my vertical compass where it is easily in sight. My green light is a top, red light at the bottom. I am thinking about changing this to red on top at my next annual. I find it helpful on takeoff as well as landing.


Sent from my iPhone using Tapatalk

Bennett, I installed my CYA at the top of the panel, above the ASI an Aspen. (I NEVER look at the Whiskey Compass - the CYA would be invisible to me there.)

I assume you verified the CYA didn't affect the compass.

[DXB]

12 minutes ago, Bennett said:

My AOA indicator (CYA-100) is mounted alongside my vertical compass where it is easily in sight. My green light is a top, red light at the bottom. I am thinking about changing this to red on top at my next annual. I find it helpful on takeoff as well as landing.



Sent from my iPhone using Tapatalk

I like that setup.   I wish EFIS systems that can display AOA based on simply a software upgrade (e.g. my Aspen)  also made a remote display that could be mounted this way..   It's a cheap and easy entry point that I would seriously consider.  But  I don't want to be squinting at my pfd while on short final trying to squeeze into a short field.

[Bennett]

Bennett, I installed my CYA at the top of the panel, above the ASI an Aspen. (I NEVER look at the Whiskey Compass - the CYA would be invisible to me there.)
I assume you verified the CYA didn't affect the compass.

The AOA does not affect the compass. We tried it in all directions - ground and flight. I think the current is too small to be of influence. The reason that I had it mounted alongside the compass was to keep it centered (almost) above the panel cover, and in sight looking through the windshield - especially when landing.


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[Bob_Belville]

20 minutes ago, Bennett said:

The AOA does not affect the compass. We tried it in all directions - ground and flight. I think the current is too small to be of influence. The reason that I had it mounted alongside the compass was to keep it centered (almost) above the panel cover, and in sight looking through the windshield - especially when landing.


Sent from my iPhone using Tapatalk

Understand, I confess I do not use the AOA much at all. But ISTM, theoretically, that the best use is on ~2 mile final, with gear down, wings level, and flaps @ full, to be able to trim the hands-off pitch to about the top of the red zone of the AOA. At that point you've got the right speed for the weight and can finish the landing by feel and sight, hands on yoke and throttle, without further reference to anything inside the plane.      

[aviatoreb]

On 1/29/2017 at 9:44 AM, aviatoreb said:

One thing about AOA indicators to maximize its utility.  I initially had one installed about 5(?) years ago.  It is an alpha systems and I got the one with voice annunciation which I like a lot.  But the indicator was mounted into a free hole in the panel next to ASI. This was good but not ideal because when you want it most, during that last minute of flight, your eyes need to be mostly outside the cockpit and looking down the runway.  So moving the eyes in and out of the airplane and readjusting the focal plane is not ideal.

So about two years ago I had the round lights indicator replaced with a different annunciator, the flat lights bar to have it mounted on the glare shield, down at the front of the glare shield right by the wind screen.  This way it is right in my line of sight during those last minutes of flight and most useful and easy to use.

 

[Bob_Belville]

4 hours ago, Bob_Belville said:

Understand, I confess I do not use the AOA much at all. But ISTM, theoretically, that the best use is on ~2 mile final, with gear down, wings level, and flaps @ full, to be able to trim the hands-off pitch to about the top of the red zone of the AOA. At that point you've got the right speed for the weight and can finish the landing by feel and sight, hands on yoke and throttle, without further reference to anything inside the plane.      

My CYA has a very loud alert, wired through the audio panel os in my headset, that goes off with the ninth, last, light which I set at least 5 kts above the stall horn.