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BBerson

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It's really about managing angle of attack instantly after engine failure. He called it unloading the wing (same thing).
Can't wait to look at an angle of attack indicator or airspeed, the instruments delay is too long. It must be instinctive to just push that nose down then start looking for the landing point.
 

TFF

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The unfunny part is it’s obvious, but not taught that way. It’s taught as stay away from stall as It’s voodoo. It’s taught as you are ok before stall and if you do stall, recover and all is ok. It should be, Hey chuckle head, push the nose over so you don’t stall. If you are close to the ground, those are the cards you are dealt.

There was a takeoff crash last week at my airport. No one hurt; totaled airplane. The instructor tried so hard to get it in the air it only made it 50 ft altitude. It had no altitude to complete the stall break. Because it had no stall break, the instructor thinks he did not stall.
 

Vigilant1

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This should be a must watch for everyone!

Thanks, the video was worth watching, and makes a lot of good points. I don't believe, however, that this "minimum maneuvering airspeed" idea will be a valuable approach to reducing GA stall/spin accidents.
GA pilots are already too focused on airspeed as a means of preventing stalls. What are the chances they'll commit more minimum airspeeds to memory and actually use them in a pop-up emergency?
In my opinion, there are two worthwhile approaches to improving stall /spin prevention. They can be used together or independently.
1) Improve awareness that AoA is the sole reason for stalls. Then, improve awareness/recognition of the conditions that lead to an AoA that exceeds critical AoA, and the signs it is occurring (buffet, control response, etc).
2) Add an AoA or LRI instrument to the panel and train pilots to include it their cross-check. I know this is highly controversial, but it is a recognition that many pilots are slow to believe things they can't see on an instrument, and the technology can now be had cheaply. The ASI is a terrible instrument for avoiding stalls, we can do much better.
In my opinion, regarding this video, the better comparison between GA and airline pilot stall awareness would come from looking at how each group uses AoA information.
 

radfordc

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The key point I took away was at the first sign of power loss push the stick/yoke forward NOW! Get the wing flying and some energy to maneuver with and then figure out the next step. This is something I learned flying ultralight/light sport planes and something I drilled into my students back then. Doing this has saved my bacon a few times for sure.
 

Daleandee

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Add an AoA or LRI instrument to the panel and train pilots to include it their cross-check. I know this is highly controversial, but it is a recognition that many pilots are slow to believe things they can't see on an instrument, and the technology can now be had cheaply.
Thanks Charlie for posting this. As an ultralight instructor (many moons ago) this fact was drilled into my head and those I had the privilege to teach. Especially in a light plane like a Challenger with a two stroke. You had better be ready for it to quit (it's gonna) and you cannot hesitate to get that nose over right now! In the heavier airplanes there is a bit more energy but as this video shows there is still very few precious seconds before the stall will happen. Don't hesitate - push the nose over!

Sometimes when stalling in a turn students would want to try to level the wings before pushing the stick forward. Nope ... gotta get that wing flying (as Pop notes "fly the wing)! Stick & rudder talks about the ability to actually fly a wing as opposed to driving an airplane through the sky.

I have a LRI and find it to be a very beneficial tool but it's only another indicator, albeit a great one, as to what the pilot should already be aware of by looking out the window and feeling the forces on the controls. Still, I highly recommend a LRI (Lift Reserve Indicator) as they are consistent and can help a pilot explore the edges of the envelope. Also very useful when making STOL approaches and departures:


Dale
N319WF
 

radfordc

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When you factor in the two Boeing and the Airbus crashes due to inability to recognize, and recover from, a stall, there may be just as many dead people, over that past two decades, from the airlines’ approach to training as from GA’a approach.


BJC
The Airbus crash was a case of improper stall procedure. The 737Max crashes I'm not so sure I would call stall recovery failures....I think it gets harder when the airplane tries to fly you into the ground.
 

radfordc

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Thanks, the video was worth watching, and makes a lot of good points. I don't believe, however, that this "minimum maneuvering airspeed" idea will be a valuable approach to reducing GA stall/spin accidents.
A long time ago Chuck Slusarczyk told me that "fifty is nifty"...meaning in a CGS Hawk (and similar airplanes) to always keep above 50 mph until your're ready to round out and land. That became my DMMS and still works for what I fly.
 

BBerson

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I think "average" pilots should be trained to stay above minimum sink airspeed. So that red mark he promotes on or near minimum sink speed should be considered. Advanced STOL pilots can go below minimum sink with wings level on approach.
 

BJC

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The key point I took away was at the first sign of power loss push the stick/yoke forward NOW!
Yes, if you are at best glide airspeed or lower. (I’m speaking of GA type aircraft, not ultralights or similar aircraft.) If above best glide speed, pitch to, or maintain, level flight attitude until the airplane slows to best glide.


BJC
 

TFF

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Even if you are somewhat fast the initial push is not bad. Push and then fix airspeed. It’s always easy to slow down; don’t let it decay without you picking to. On the biplane forum the topic came up. Because of the aerobatic nature of the group they were arguing on how hard to push. Some were worried about negitive G stalls pushing hard. Now we are getting overzealous. If you are so close to the ground you need to be in a landing flair, hopefully you have the awareness not to push. If you are 150 ft, you’re just stuck, but might as well control where you hit instead of random if you stall. Overall there is usually a choice or two on where to go even if not perfect. The places that don’t are usually on the minds right from the start.
 

BJC

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The Airbus crash was a case of improper stall procedure. The 737Max crashes I'm not so sure I would call stall recovery failures....I think it gets harder when the airplane tries to fly you into the ground.
Same thing: not in control of the airplane and letting it hit the ground.


BJC
 

davidb

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Yes, if you are at best glide airspeed or lower. (I’m speaking of GA type aircraft, not ultralights or similar aircraft.) If above best glide speed, pitch to, or maintain, level flight attitude until the airplane slows to best glide.


BJC
IMO, even if at cruising speed it would be best to start “pushing” towards the attitude that gives best glide speed. The “push” in this case would be gradual. A focus on maintaining altitude until achieving best glide speed seems counterproductive. I think it’s best to quickly get the mind focused on the descent so as to get started on analyzing the best crash site.

Without getting bogged down in semantics, I like his emphasis on getting the nose down as the first, reflexive action.
 

BJC

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IMO, even if at cruising speed it would be best to start “pushing” towards the attitude that gives best glide speed. The “push” in this case would be gradual. A focus on maintaining altitude until achieving best glide speed seems counterproductive. I think it’s best to quickly get the mind focused on the descent so as to get started on analyzing the best crash site.
I think that we are in agreement.
If above best glide speed, pitch to, or maintain, level flight attitude until the airplane slows to best glide.
My comment was, from above best glide speed, to pitch to a level attitude (not to try to maintain altitude) as a rough proxy (assuming no AoA indication or reserve lift indicator that has been calibrated for best L/D) for best L/D.


BJC
 

davidb

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I think "average" pilots should be trained to stay above minimum sink airspeed. So that red mark he promotes on or near minimum sink speed should be considered. Advanced STOL pilots can go below minimum sink with wings level on approach.
Isn’t minimum sink speed significantly slower than best glide speed?

I think he was saying fly at 1.4 X stall speed which for my plane is about 5 knots faster than best glide speed. No idea what minimum sink speed for my plane is (maybe 5 knots below best glide speed)?

I agree it is better to stay above best glide speed and his 1.4 X stall speed seems about right for me. Heck, that probably approximates best glide speed with a 5 knot headwind.
 

TFF

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Gliding for distance is a precision maneuver. I think the action is about get airspeed then decide. His minimum maneuvering speed keeps most people out of stall until they have a plan. Most of this is about being below 1000 ft agl if not below 500 ft. If you are 6000 ft agl, you have a lot of time. Do it at 6000 ft and you can acknowledge you did learn the training. At 600 ft, you will be on the ground before you understood you got it right.
 

Topaz

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Isn’t minimum sink speed significantly slower than best glide speed?...
Yes, because as any glider pilot knows, there are actually two "best glide speeds," each having a different purpose. Minimum sink airspeed keeps you up the longest - your rate of decent is the slowest. What is called "best glide speed" in most power-plane POH's is actually the speed for the best Lift/Drag ratio, which gets you the farthest distance in a glide. Unfortunately, most POH listings for powered aircraft don't give the minimum-sink airspeed. All glider POH's do. It's usually a few knots - sometimes as little as 2-3 - above the minimum controllable airspeed ("stall" speed, if you insist).

The most similar situation to this video, in a glider, is a rope break on takeoff, on any kind of towed takeoff. And you get the nose down now, now, NOW. You don't wait for the airspeed to start to decay and the resulting AoA increase, just asking for a stall. There is absolutely no difference when you have the tow plane bolted to the nose of yours, under the cowl. If you no longer have power, get the nose down and maintain good airspeed/AoA. Nothing else matters until you do.
 
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