"This is your Captain speaking, We have a slight problem and need to quickly shift our centre of gravity forwards about 10 feet.......... So, Free Champagne for the first 40 economy passengers to get to the cockpit door !!!". :)
_"...stalling an aircraft is something we are trained to try to avoid at all costs..."_ Your flight instructor: _"Today you are going to practice going into stalls..."_
Hi, Petter! There is one practical use for a super-stall that some of your viewers may not know about... I used to fly 'free-flight' model aircraft when I was a kid. They were little (2' or 3' wingspan) gliders or rubber-powered planes built from balsa and covered with strong tissue paper. There was no radio control gear (it cost a fortune back then!) so the planes were self-stabilising and flew in a gentle turn all by themselves. Getting the 'trim' perfect was a big challenge, and taught you a LOT (unofficially) about aerodynamics! Unless the weather conditions were absolutely calm, on a good flight of 6 or 7 minutes - despite being trimmed to fly in a constant gentle turn - the planes could drift a long, long way downwind. You kept fit by retrieving them; I used to chase after mine on my bike! But occasionally you'd encounter a bubble or column of warm rising air, and then you were in trouble because the model would fly higher and higher, to hundreds or even thousands of feet, sometimes flying right out of sight, never to be seen again. It was exhilarating, but very sad because your lovely plane was gone for ever. So we used to fit so-called 'de-thermalisers' to our models. These were simple mechanisms which, after a set time, released a catch on the rear of the tailplane that caused it to tilt upwards to about +70°, putting the model into a massive and unrecoverable super-stall. Even in a strong thermal, the fully-stalled aircraft would head for the ground, wings level, and land gently. De-thermalisers saved a lot of tears... Unless the thermal was really strong, in which case the stalled model (which only weighed a few ounces), would continue to float up, up and away like a balloon; not actually flying, just tumbling and drifting. That didn't happen often, though. Maybe you were under a storm cloud, where you shouldn't have been flying in the first place! Anyway, I just thought it was worth mentioning that, sometimes, a super-stall can be a really useful thing...
Had something similar.... a 'bungy' based launch system, which would trigger the rudder so that the glider would circle. And then a thermal fuse which would trigger the stall after a length of time.
Old B727 FE lived through this induced by Super Captain. Being an acro pilot and aware of our aft CG, I warned the Capt he was playing with fire flying trough stick shaker. As he lost control I grabbed FO yoke and turn full left to raise flight spoilers. This brought us nose down and the FO took over recovery. The Capt still will not talk to me, but I saved all of us. We were on departure climb out. You have to know the situation and keep your head. Great Talk.
I wish I'd had a science teacher like you at school. They never seemed comfortable explaining stuff to us and I got bored and lazy. This is good to listen to - thanks!
The problem with school is when you don't see the relevance of how you'd ever use that in real life. Sometimes you need to be given some "fun" examples to keep the child's attention.
What you said about the movement of the center of lift when the wing tips stall reminded me of a spin recovery technique that was developed for the F-14, which was notorious for entering unrecoverable flat spins. The technique involved sweeping the wings fully aft, thereby moving the center of lift aft of the center of gravity, causing the aircraft to nose down and fly out of the spin. It did, however, require at least ten thousand feet of altitude to execute.
The F14 issue was mainly at low speed during approach to landing. It would get a compressor stall if slipped or skidded on the turn to final, while also being below single engine maneuvering speed(which was high due to wide engine placement), so quickly adding power to the good engine would actually cause or increase a spin. All while 200 feet above the water.
This reminds me of an interview with Chuck Yeager: "the airplane was in a spin and had the aerodynamics of a set of keys. So I put it in a regular spin and pulled out of it." Just another day at the office.
@@FutureBoyWonder Depends on a lot of factors. Fatigue is one I know of. Example: Colgan Air Flight 3407, where an exhausted flight crew was mentally unable to correctly interpret the warnings, and ended up causing the Stall themselves.
In airplane design, T-Tails have to be in a certain ratio of height to distance from the center of lift. This ratio makes sure that the tailplane is above the wake area in a stall and so prevents deep stalls. The same applies to rudders. The design of rudders must be so that a useful part of the rudder is still outside the wake area and can be effective in a stall situation. Lessons leaned from the accidents in the past. One thing you can also do in a stall is shifting the center of gravity. Like all passengers running forward. This is not very likely but could work. I also works in a flat spin, which is another very dangerous situation you would not want to get into, because then all surfaces stall simultaneously. This is prevented usually by having the center of gravity before the center of lift by contruction and loading. Which is a requirement in designing an aircraft. There is much more to it that has to be considered during design.
I don’t know that you will see this comment as this is an older video, but you are an amazing teacher. Your understanding and passion for aviation and the physics behind it are second to nobody I have ever watched. I discovered your channel about a month before flying my family to Florida for my wedding/vacation and binge watched so many of your videos. I felt very comfortable flying having a decent understanding of what I would watch the wings do from takeoff to landing, the sound of the engines, hearing the hydraulic system (a320) Thank you for making all of the content you do. It’s motivating to get my pilots license
When I learned to fly my instructor felt it beneficial to teach me how an aircraft stalls, can enter a spin (spiral dive) and recovery. The flying school had several Tomahawks each with its own stall characteristics. I got pretty good at recovery and had no fear of the stall or dealing with it as it happens. After getting my PPL I decided to do an IMC rating and was taken out by a new stand in instructor I didn't know and in marginal conditions. He wanted to do recovery from unusual attitudes and we were in marginal conditions (I expect he wanted the money for the flight). The actual aircraft we took had a nasty 'super slippery' wing drop when it stalled. He instructed me to go to 5000 feet and I insisted on 7500 feet which he felt was excessive but I did it anyway. I also said the aircraft had a vicious wing drop but he just laughed. So there I was on with a power off nose high stall and the aircraft flipped into a spiral dive, it was rare you could catch it with this aircraft. He said nothing at all. I looked across and he was frozen, I recovered the aircraft. He said pretty much nothing for the next 15 minutes then said it was a bit marginal and to go back. Never saw him again. The PPL now apparently only teaches you to recognise an approaching stall and prevent it happening, very few get to experience the spiral dive which can be overwhelming when it happens.
Suggest respectfully that you go for more lessons: spins and spiral dives are different things-with different recoveries. Hence the need for lessons. Happily I’m both a flying instructor, and I have a Pitts S2a, an ideal platform for such lessons! Cheers, Paul Stanley
That. was. SO. INTERESTING! I never thought about the fact, that the aircraft's design could either stop or even worsen a stall. And now I finally know, what those little metal plates on the wings are (the vortex generators)! I was about to say, that the swept wings, trijet design sounds like a terrible idea with the new information, but I'm happy to hear about all those counter-measures. Thank you for the excellent video!
@@TheEDFLegacy Uähh... Flat spins, this is what i'm afraid of! I do some glider aerobatics and sometimes i spin the glider, the SZD-59 for example, spins realy nice. But a flat spin, this is pure horror!
@@TheEDFLegacy And not just tails. In the trijet days, sometimes the inlet for the rear engine would fall into the aerodynamic shadow of the plane, rendering it unable to perform. If I am not mistaken, Gulfstream made the tails on their jets taller to avoid this over the years.
Turn to tight and the inner wing will stall before the outer, this is why pilots are taught let it slip around turns at low level rather than use too much rudder :)
This showed up after i looked up the pulova 621 cvr. It was a super stall and you can hear the pilots panicking and screaming as they are about to hit the ground
That is what took down AF447. Look at the accident report. Mentour, you know as well as I do that a loaded A330 can't climb at 7000fpm at any altitude, much less from cruise altitude. That aircraft was pushed upwards by a strong updraft in the embedded thunderstorm line, and after exiting that updraft they found themselves high, heavy, and at a positive AoA. The aircraft then entered a deep stall which of course blanked out the tail effectiveness. Add in the fact that super-cooled liquid (not ice pellets for god's sake..) entering the pitot tubes and freezing, which of course affects AoA and airspeed. The co-pilot didn't help things by continuing to pull up, which of course aggravated the situation and prevented recovery. If I am correct, there is a slight window of time where they could've rolled the aircraft to the right, quite a lot actually (certainly to the point of discomfort or alarm to passengers not familiar with flying or upset attitudes). The aircraft could then use the fuselage to slow it down some and hopefully recover. Outside of that, anything you'd do to recover would've oversped the aircraft horribly, or outright stressed the airframe to the point of breaking things or in-flight breakup. A sad situation for sure, but an example of a deep stall, and more importantly, an example of why we do NOT fly into thunderstorms.
Petter, I have the perfect career in mind for you when you stop flying. How about becoming a cruise ship’s captain? You have the perfect calmness and fun personality that naturally attracts and commands attention. Just a crazy idea of mine. Safe skies my friend.
The depth of your knowledge is breathtaking and fascinating. Your content is too good for the usual over dramatic tv programmes I have seen. Amazing. You have a calming and respectable manner, totally impressive. And you are a fellow ginger!!!
Depending on the aircraft and load, you could have 50 passengers run forward, that's be a significant enough weight shift. On a much smaller scale, this worked years ago for two fellows who got a Yankee into a flat spin, they had to open the canopy, stand up, and lean forward over the windscreen.
@@matejlieskovsky9625 You're not going to believe this but occasionally there are no links to things that happened well before the Internet. As well, I once read a verified report of a Globe Swift (IIRC) that had a propeller blade depart and shortly thereafter the engine followed the propeller's example. The pilot was able to regain control during the ensuing loop and successfully got the aircraft on the ground intact (or what remained of it). I once, by virtue of faultless stupidity, managed to half snap roll a Cessna 150 upside down at no more than 50 feet off the ground. I did not crash, and went on to a long career of less stupid aviation. I have no link I can send you but it did happen.
I'm a year late but I have to say, I love the way you write. It is very entertaining and to the point. I would imagine that people like listening to you speak irl. :)
Doing stalls and my first solo are two of the most memorable things during my PP training. Third would be first solo cross country. Practice stalls in a 152-172 Cessna a were quite exciting. Great video, blue skies!
I read the news about the Brazil crash, saw the term superstall here and there and arrived here for knowledge. Thank you. May the souls in that Voepass ATR and their loved ones find peace.
My wonderful nephew who is still training to be a pilot, took me for a spin in a little Cessna and once high up in the air, he stalled the plane. My life flashed before my eyes as I saw the tiny houses below me. I love my wife more than ever!
he "took you for a spin" -well that can be dangerously misinterpreted
5 років тому+2
Adorable and warm personality of this pilot makes me watch all of his content even though I’d never wish to be any kind of pilot whatsoever 😊. Great stuff, kudos!
In before I get notification:) Great video btw. Also mad respect to experimental pilots who try to get the new aeroplane to all sorts of unfavourable conditions such as stalls to see how it will behave.
Indeed, deep stall was discovered on the BAC 1-11 after a fatal crash during flight tests, and a number of other aircraft have crashed during flight testing due to deep stalls.
yeah i'll just enter a flat spin to set up procedures to get out of it if I'm not completely absolutely without question totally beyond any meaningful help overwhelmingly (duck)ed
You mentioned the BAC (then Vickers) 111 which had the rear mounted engines and which crashed through a super stall back in 1963. I was an air cadet in 261 Guildford at the time, and one of our officers worked at Wisley and got us an air experience flight on one of the development 111s. This was only a few months after the tragic loss of one of the aircraft and all the crew, through the super stall that you referred to. There were about 20 of us and when our coach drove onto the flight tarmac we could see a half dozen or more 111s with rocket motors fitted, presumable for propelling the 111 out of the super stall and enable the continuation of the test program. As a kid of course , I didn't realise the full impact of what we were doing and didn't worry much about it. Today, as a retired teacher, I am somewhat horrified by it all, especially when I found out recently we were doing some of the same tests that the crashed 111 had been doing. There was a large tank of water in the centre of the aircraft and they were pumping the water from end to end of the aircraft to test the auto pilot's response to the shifting of the centre of gravity of the aircraft ( Centre of gravity used correctly here, by the way.) And either to keep us amused, or because they wanted a stronger effect, they had us running from end to end of the mostly seatless cabin in conjunction with the water pumping!! As I say I am somewhat horrified today!! I would just like to add that the crew who gave their lives in the crash enabled flying to be made safer for all the rest of us and I hope no more flippant remarks are made here.
Ive stalled out my planes in IL2. Friggin terrifying stuff, even in a video game lol. I got decent at recovering. Engine to idle, counter rudder, point the nose down and dive, gain speed, engine to max power and pull out carefully. P-51 loved to stall on me alot.
P51 was the first plane with laminar flow wings. It was the secret of its huge range (=low drag) but a real problem when the flow ceases to be laminar ...
That aircraft with ribbons attached to the top of the wing provided a really good visualisation of the airflow, and the turbulence when the angle of attack gets too high. I'm finding all of your videos really interesting and informative. The more that I watch, the more I realise just how complicated flying an aircraft is.
Soviet aircraft utilized wing fences on the top of swept wings to maintain airflow. Military and aviation folks in the United States would joke that the wing fences were to keep the airflow from defecting off the wing.
Google the Trident! I was on one when it got buffeting on approach at about 100ft and slammed into the ground with the engines spooling up. Thank God we were nearly down. Calm hot day and must have grabbed a tailwind. It was in the 60s I think returning from Nice.
I hadn't been on a flight since 2012 but I found your channel a couple of months ago after starting a new job where I was told I might have to fly around the country for work. I take wing and exit seats every time now so I can watch how the plane is flying, and also so I'm able to help if need be. Been on 5 flights over the last few weeks and it's been great knowing what every sound, action and stage of flight is.
Maintain thine low angle of attack lest the earth rise up and smite thee! I fly agricultural aircraft (Air Tractor 502 ) and we have to think about angle of attack continually because of flying steep repositioning turns all day long.
Lovely coincidence. I've published a very similar video yesterday, in Portuguese, talking about the importance of understanding AoA, while demonstrating that in flight on my Cirrus. As always, great video, fellow pilot!
Great video Mentour i enjoyed it, i remember when i had a flight in a Piper PA28 and the pilot did a stall recovery demonstration it was fun! I love the captions you put on Patxi too, have a great weekend my friend.
Hi dear Captain,i never could be enough greatful for all the pertinent content you brought us mainly in addition to all that regards aviation ,you are helping us to set up a succesful mindset ,a way of thinking and visualizing things from diferrent perspectives to get the right step to be held.thank you very much 🌹🌹
This happened to me under similar circumstances. I simply induced a spin by throttling down and applied hard-left aileron. After a 90° bank action, I slowly throttled and applied opposite aileron and was back to enjoying my day
Mentour pilot, this was a great video, thank you for all the brilliant explanations. I know that the Max has now become a taboo but it's impossible to think of stall nowadays without thinking of the Max. So I think that the logical conclusion to this subject is another video specific for the Max, explaining the aerodynamics involved in that design and the role of the MCAS. Thanks.
Richard Reed There are similarities, which Boeing were denying, because a stick pusher requires more certification changes, and type specific training.
Videos like this remind me how crazy combat aircraft and pilots can be. There is a report from Vietnam where an F4 pilot intentionally "detached" from flight into a tumble to shake a chasing MiG. He then recovered behind the MiG and shot it down. The fact he could do that, recover, and not rip the wings off is insane. Especially in an era with very little computer assistance for the pilot.
As a new fan of yours... this pops up! I'm Not an aviator... but am a retired Gas Turbine Mechanic from the Navy! Sooo looking forward to this video! So much so... I have to.comment before watching! Lol
I need to research this more.. It certainly would makes sense in a logical first-pass. I presume increased drag is the rational behind their lack of use?
@@topiasr628 Canard are aerodynamically complex and take a lot of careful design to function properly. In general the benefits are not seen to warrant the increased design / construction / maintenance costs.
Theoritically you can do this. Practically you will have to get the passengers quickly moving up a slope in rough conditions without panic. Quite a challenge.
Would dropping the gear and/or flaps help you to overcome a deep stall? My thinking here is that adding drag below the aerodynamic midline and behind the centre of lift might help to pitch the nose down.
A very good video about deep stalls. I think it would be good to mention that most modern airplanes use wing "washout" to ensure the wing stalls inboard first and wing tips last. The wing structure is such that the angle of attack at the inboard end of the wing is greater than the angle of attack at the wing tip, ensuring that aileron control is maintained as long as possible in the stall. Also, while the 737 doesn't have a mechanical stick pusher it does have a somewhat equivalent system called "Feel Shift". As the airplane approaches a stall the first warning to the pilot is the stick shaker. If the angle of attack continues to increase the Elevator Feel system will increase the column force resisting the pilot's input thereby pushing the column in the nose down direction.
Excellent presentation. However, I would add that any aircraft can potentially be inadvertently deep-stalled under unusual conditions such as abrupt environmental turbulence, versus "typical" aerodynamically induced aberrations. The condition may also not meet the test of the classic stalled condition - with a stick-shaker - as opposed to a vertical 'inertia,' rather emulating a vertical bow wave. The B-737 100, 200, 300 (presumably the 500 series) are known to encounter a loss of elevator authority during moderate-heavy icing conditions; due to disturbed airflow from approach flap settings, coupled with the icing buildup on the horizontal stabilizer. I've personally witnessed 'square' ice on the horizontal stabilizer. Altitude and time permitting, if possible, I'd encourage a thought to turning off any power limiting features in an emergency, so as to maximize "survival thrust'" - damn the engine replacement cost. Whether you accelerate through the 'condition,' or use engine differential thrust and/or flaps and landing gear to maneuver/break out of the 'condition,' the awareness of the possibility and early recognition are paramount. In the case of the typical airliner, it's possible to encounter such pertinent 'onset' conditions due to an abrupt higher-than-normal air temperature deviation during cruise or climb, even without vertical gusts from thunderstorms, for example. The FMC and other automated features may not give timely clues or 'solutions.' As an indicative but extreme example, in November 1968, in Alaska, an F-27 encountered a vertical 'sheer' in clear air at 20,000 feet - calculated by the NTSB at 29Gs. Its impact was far more vertical than horizontal. In aviation, anything is possible - and probable.
Indeed. It is a popular and dangerous misconception which seems to be taught that "only T-tailed aircraft can enter a deep stall" and I even noticed one experienced pilot commenting on the AF447 incident that "the aircraft was not in a deep stall because it is not a T-tailed aircraft". Any aircraft can enter a deep stall if the horizontal stabiliser is stalled in addition to the wings. I'll repeat that. Any aircraft can enter a deep stall! The combination of a swept-wing and T-tail is most susceptible to a stall, due to the poor stall characteristics of the swept-wing as described here (alongside the shift forwards of the centre-of-pressure as the AOA increases on most wing designs, not mentioned here) and the turbulent flow over the horizontal stabiliser reducing elevator authority. However, any T-tail or swept wing is susceptible to a deep stall and even a non-swept wing craft under the right conditions could experience a deep stall. As Ralph mentioned, vertical sheer/extreme updrafts which result in an abrupt change to the angle of attack can in theory stall the horizontal stabiliser and it is possible that this is what was encountered by both AA8501 and AF447 since both planes climbed beyond their performance capabilities at high altitudes, suggesting that they encountered updrafts which resulted in a high vertical speed (this is mentioned in the reports as a possibility but NOT directly linked with a necessary change in the AOA). This type of stall is doubly dangerous as the abrupt transition from normal flight to a deep-stalled condition would not result in a stall-buffet as the airflow would detach from the entire upper surface of the wings and canards at once. This makes the deep-stalled condition even more difficult for pilots to diagnose. We may never know if AA8501 and AF447 were in deep-stalled conditions, as the pilots flying failed to recognise the stalled condition at all until too late. The response of AF447 to side-stick inputs and rudder commands by the FO during the final seconds of flight indicate that a deep-stall was probable and had the SO pushed forward on the stick it may have had no effect whatsoever, but since he didn't we can only speculate. Nevertheless, it seems shocking to me that so many pilots believe the myth that not all craft can enter a deep-stall. Modern aircraft are returning to designs where the body and nacelles produce a significant fraction of the total lift. In a stall-condition, this lift is a stabilising factor which helps to prevent rolling and yawing motion during the stall which could lead to a spiral descent. However, in a deep-stalled condition, this lift can stabilise the craft in a gliding descent with nose-up attitude, keeping the horizontal stabiliser in a stalled condition. Tricky business...
Hello I never learned stalled wings that way. I learned from Lee Mercure that was one of the original creators of aviation in the USA and the world that, YOU LOAD THE WINGS AND UNLOAD THE WINGS . That is the correct and elegant way to explain a stalled airfoil. Saludos aviador
Some VC10s had twisted wingtips to give lower angle of attack at the tip, meaning it was less easy to stall the tips, and so the aircraft could fly slower and also higher than the unmodified versions.
The deep stall is very well explained in this video. Congratulations. On the FlyJSim Boeing 727 for X-Plane flight simulator, with Ultra-realistic flight model, the "Deep Stall" is very well simulated. Stalling a B727 T-tail will get you in an unrecoverable "Deep stall" in no time, with no aileron, rudder, elevator and/or engine control. Unless the deep stall occurs at at 30,000ft, and the plane drops 20,000 ft.. it may by chance get into an attitude, that may allow to recover... and that's a maybe. It's nasty. Otherwise, very aerodynamically sleek, super-clean, fast and pleasant to fly T-Tail. Just don't stall a T-Tail because it will show you it's bad side, and will bite you!
I'd sadly skipped this one, thinking “Aviation 101”….but am So Very Glad i finally watched! This is a must see! For a host of reasons:No Spoilers, promise. (Graphics are just too much fun!)
Hi Mentour. Very interesting video (as usual). In the Danish Air force we use to fly the Draken, and when they were phased out, at number were sold to an American Flying School - if I remember correctly - as this airplane was actually able to recover from a super / deep stall (if they had altitude enough). I am not sure exactly how they did it. I have not been able to find any videos here on YT, where you can see it . Cheers Adam
The second sentence was intentionally omitted. I'll reinsert it for clarity...... "The aircraft will fly like a leaf ... to the ground. It will then act like a bomb."
I think you'll find that every aircraft with a stick pusher, the crew were advised of its existence and how to manually override it (pull harder) and cancel it, as part of their type training.
A friend built a model 1-11 some years ago. While at the design stage this issue was discussed. One interesting idea that was raised, but not implemented, was the addition of a small explosive device on the cockpit roof. Designed in such a way so as not to damage the airframe, but powerful enough for the blast to kick the nose down. I wonder how much force would be required on a full size airliner? Deploying a drag parachute from under the aircraft rear was also discussed. But I'm sure the builders have gone into this more than we have and I do not see any of these fitted.
If I recall from my aerodynamics class, deep stalls tend to affect T-Tail configurations more, because the slipstream created by the wings renders the elevators useless.
Les Turner correct, on aircraft that have the horizontal stabilizers behind and slightly above the wing (the sheer majority), upon any major upset, the stabilizer will be freed from wing wash. If i’m not mistaken, however, the horizontal stabilizer can itself stall, rendering the elevator’s up authority ineffective. Note the Saab 340 and Metro’s that have the ‘cruciform’ tail. Can be deep stalled, at a higher angle than on a low mounted stabilizer, yet far lower than a T Tail (the purpose of which is either to clear tail mounted engines, or clear turbulent and highly variable prop blast.
Upsetraygun2 T Tail in deep stall? I would doubt it, the prop wash would still be blown roughly parallel to the engine’s axis, though would also be blown backwards with the still forward speed of aircraft, though the differental of prop blast speed to rearward speed would be so high, would likely pass behind the aircraft well below the stabilizer. The advantage of propellor over turbofan engine is that a turbofan can get compressor stall, and even be completely blocked, by high angle of attack at low airspeeds, a propellor however, being completely unconfined, really doesn’t care from which direction the air is coming, given that it is sitting completely unconfined, in it.
@@jaysmith1408 That's what I meant sorry bad phrasing. With the horizontal stabiliser directly aft of the prop, such as a c172 for example. You should be able to increase your throttle to create lift over the elevators. Where as with T-tails you can't.
Upsetraygun2 no worries, if i’m not mistaken, there is an advantage to having the stabilizer in the clear of prop blast, clear undisturbed air, less blown debris, not behind any fuel, oil, ice, other miscellaneous parts that have grown tired of being attached to the aircraft. However, primarily, this is disputed for extra weight, control complexity, and as you said, does not have the advantage of prop blast. The downside to the C172 method, is similar to the issue with the lockheed electra’s wing. The electra has massive propellors, and a fairly small wing. On good days, the propellors spin, effectively creating its own lift. On bad days, the propellors create drag, no thrust, and highly turbulent air, where the aircraft would almost fly better with the entire engine missing. Once the propwash is gone, so is the gross majority of the lift. At this point it’s the Ford/FCA/GM debate, six of one, there are different methods, they all work, depends on the application. As well, as demonstrated with flow separation, the advantage of being downstream of the propwash, is just that, only when directly downstream, minimal angle of attack. At a higher angle of attack, the stabilizer will no longer be downstream of the propellors, the flows from the propellors, and over the stabilizer, would be parallel, and adjacent.
Hey P..., just out of curiosity at first and then interest due to the catastrophic loss of life when in a Crash , I have watched most of your videos. I am an Octogenarian so no more air travelling;now
Since engineers are fully aware of potential super stalls or deep stalls one would think they would create a new control surface that appears in these dire situations. Instead of only horizontal control surfaces in normal flight. Maybe they'd be a button that now activates a pop out Vertical control surfaces that provide pilots ability to get plane in a high left or right bank to get nose to drop and regain needed airspeed. Almost like a large rudder but aligned downward instead. Instead of a yaw one would get a roll instead with ailerons are in turbulent air & no longer effective. This new Emergency Pop out veritical type rudder control surface needs to also be forward to be out of turbulent air.
Yup, 10/10 for these videos. Well done MP. OK, say a super-stall at 30K feet? Dump fuel from ONE wing? If there is time, then one wing will drop, and also asymmetric drag, which might get the nose down, and eventually, speed up?
Jordi Tribo Everything about MCAS on the MAX touches on points addressed in this video, longitudinal stability, horizontal stabiliser, and elevator effectiveness.
@@roku_nine - Not so simple, much more roundabout and sneaky than simple penny saving. Using a sticky pusher would have made the 737 pretty much a different aircraft, in terms of certification process. It meant adding years to the MAX time-to-market, leaving too many companies tempted to buy the Airbus A320 NEO, which could be an issue down the road as most small companies tend to use planes from a single manufacturer, because it simplifies logistics. So, once an Airbus is inside a company... Boeing was so much in a hurry that they went with a botched automatic system that used a single AOA sensor, something that they likely knew had to be re-implemented down the line - as they did with a somewhat similar system used in the NG - but at the moment sped things up, as a single sensor system could be certified much faster. We all know how that turned out. If Boeing had accepted the inevitable delay and just went with a dual-input MCAS from the start - i.e. the fix that they are developing - we'd would all be just in awe of how gorgeous the MAX looks with his badass big engines...
Oh, that reminds me of my old sim days. Those deep stalls were scrary when flying a f16 due to design instability. The procedure was to use a switch to override some precautions and then u have to pitch up and down in the same rythm. When upside down, it's almost impossible to recover.
The Trident was a high T tail aircraft and could super stall. The only way to get out of one was to fire a parachute out of the back to lift the tail which was done on initial proving flights. A superstall was the cause of the Staines crash near Heathrow in 1972. Someone retracted the leading edge droops ( now called slats ) which could be controlled independently of the flaps on the Trident. They had all the warnings but ignored them and cancelled the stickpusher. Incredibly Tragic.
One of the saddest accidents I have read about. Because of the lack of C.V.R, we can only guess as to who exactly retracted the droops. Due to the probable incapacitation of Captain Key, the aircraft did not reach flap-retraction speed, and the lack of visible cues and experience of the 1st and 2nd officer did not help either.
@@Vincent_Sullivan The Tupolev 104, being based on bomber, had a parachute to help it stop as its brakes were dire and had no reverse thrust. It also had swept wings and wing fences to stop the lateral air drift...
Huge flight enthusiast, not a licensed pilot. I am in the simulator daily though. The other night I was practicing stall recoveries from the safety of my house. Was 20000 feet off Mount Blanc middle-of-the-night IMC in a citation. When into a super stall. Dropped 14,000 ft before hard right rudder finally began to get control of the aircraft. Leveled out at 3500. With no formal training after watching this video it makes perfect sense to me as to why I was completely helpless no matter what inputs I made
mentour = 10/10 youtuber
Thank you!! You are far to kind! 😃
@@MentourPilot More like 11/10. If I don't get my renewable energy engineer job then commercial airline pilot is my alternative. Cheers mate!
@@MentourPilot Definetely you are, sir! You really deserve it!
@@MentourPilot, wrong. It is well deserved, Sir.
Sure it's quality content. The ads turn your 10/10 to 3/10. Downvoted
"This is your Captain speaking, We have a slight problem and need to quickly shift our centre of gravity forwards about 10 feet.......... So, Free Champagne for the first 40 economy passengers to get to the cockpit door !!!". :)
LOL
Awesome!
Reman1975 brilliant, love it :)
Epic comment, thx for doing my morning lol
This would actually possibly work.
Stalled plane and "Terrain! Terrain! pull up!" - a really bad day! Understatement of the year!
@@snackler6102 sponsored by the angel of death
@@snackler6102 Pilots may have been wishing they had worn their pull ups that day.
@@snackler6102 that has to be the best comment haha. Providing you meant pull ups as in the nappies
Unfortunately, I'm revisiting this vid because of a crash today in Brazill of an ATR 72-500 in an unrecoverable stall. You explained it very well .
Same here
_"...stalling an aircraft is something we are trained to try to avoid at all costs..."_
Your flight instructor: _"Today you are going to practice going into stalls..."_
To avoid the stall,you must fell the stall..😜
Yeah compare stalling a cessna to an airliner
@@andreighitescu586 I've never flown an airliner, lol.
I remember when my instructor was basically saying the same thing as they were bringing the engine to idle
@@sr-dt3pl kkkkkkkkkkkkkkkkkkkkm
Hi, Petter! There is one practical use for a super-stall that some of your viewers may not know about...
I used to fly 'free-flight' model aircraft when I was a kid. They were little (2' or 3' wingspan) gliders or rubber-powered planes built from balsa and covered with strong tissue paper. There was no radio control gear (it cost a fortune back then!) so the planes were self-stabilising and flew in a gentle turn all by themselves. Getting the 'trim' perfect was a big challenge, and taught you a LOT (unofficially) about aerodynamics!
Unless the weather conditions were absolutely calm, on a good flight of 6 or 7 minutes - despite being trimmed to fly in a constant gentle turn - the planes could drift a long, long way downwind. You kept fit by retrieving them; I used to chase after mine on my bike!
But occasionally you'd encounter a bubble or column of warm rising air, and then you were in trouble because the model would fly higher and higher, to hundreds or even thousands of feet, sometimes flying right out of sight, never to be seen again. It was exhilarating, but very sad because your lovely plane was gone for ever.
So we used to fit so-called 'de-thermalisers' to our models. These were simple mechanisms which, after a set time, released a catch on the rear of the tailplane that caused it to tilt upwards to about +70°, putting the model into a massive and unrecoverable super-stall. Even in a strong thermal, the fully-stalled aircraft would head for the ground, wings level, and land gently. De-thermalisers saved a lot of tears...
Unless the thermal was really strong, in which case the stalled model (which only weighed a few ounces), would continue to float up, up and away like a balloon; not actually flying, just tumbling and drifting. That didn't happen often, though. Maybe you were under a storm cloud, where you shouldn't have been flying in the first place!
Anyway, I just thought it was worth mentioning that, sometimes, a super-stall can be a really useful thing...
Elli P Interesting story! The Virgin Galactic spacecraft uses a similar tailboom stabilising mechanism during descent.
Had something similar.... a 'bungy' based launch system, which would trigger the rudder so that the glider would circle. And then a thermal fuse which would trigger the stall after a length of time.
That is definitely a good mechanism to in stall.
Interesting application. I guess it can be useful as long as the plane is unmanned.
That's really cool!
Old B727 FE lived through this induced by Super Captain. Being an acro pilot and aware of our aft CG, I warned the Capt he was playing with fire flying trough stick shaker. As he lost control I grabbed FO yoke and turn full left to raise flight spoilers. This brought us nose down and the FO took over recovery. The Capt still will not talk to me, but I saved all of us. We were on departure climb out. You have to know the situation and keep your head. Great Talk.
Wow why would he not speak to you ? Was he too embarrassed
I wish I'd had a science teacher like you at school. They never seemed comfortable explaining stuff to us and I got bored and lazy. This is good to listen to - thanks!
The problem with school is when you don't see the relevance of how you'd ever use that in real life. Sometimes you need to be given some "fun" examples to keep the child's attention.
maybe if teachers got paid like successful youtubers... ;)
@@scrrification Yep maybe. But I had some extraordinarily good teachers that weren't paid that much.
What you said about the movement of the center of lift when the wing tips stall reminded me of a spin recovery technique that was developed for the F-14, which was notorious for entering unrecoverable flat spins. The technique involved sweeping the wings fully aft, thereby moving the center of lift aft of the center of gravity, causing the aircraft to nose down and fly out of the spin. It did, however, require at least ten thousand feet of altitude to execute.
The F14 issue was mainly at low speed during approach to landing. It would get a compressor stall if slipped or skidded on the turn to final, while also being below single engine maneuvering speed(which was high due to wide engine placement), so quickly adding power to the good engine would actually cause or increase a spin. All while 200 feet above the water.
The general unreliability of the TF30 didn't help much in that area, either.
This reminds me of an interview with Chuck Yeager: "the airplane was in a spin and had the aerodynamics of a set of keys. So I put it in a regular spin and pulled out of it." Just another day at the office.
@Agent J agreed. This applies to so many aspects of life.
RIP Chuck Yeager. My first hero.
Funny enough, one of his closest calls was in a plane that was notorious for getting in to a deep unrecoverable stall - the F-104 Starfighter.
Yea...but think of passenger aircraft,like a320... passengers will fly like another aircraft inside fuselage.
@@sr-dt3pl They should be wearing their seat belts. I rarely take mine off, I trust the airline and the pilots, but no turbulence.
Pilots: *fail to notice stall warnings*
Stick pushers: Fine, I'll do it myself
I don't understand how a lot of pilots managed to ignore all this when found out during a crash
@@FutureBoyWonder Depends on a lot of factors. Fatigue is one I know of. Example: Colgan Air Flight 3407, where an exhausted flight crew was mentally unable to correctly interpret the warnings, and ended up causing the Stall themselves.
MCAS: _Nothing to see here_
@@joez.2794 indeed, nothing to see here - avoidable crashes.
*laughing in Airbus alpha protection*
In airplane design, T-Tails have to be in a certain ratio of height to distance from the center of lift. This ratio makes sure that the tailplane is above the wake area in a stall and so prevents deep stalls.
The same applies to rudders. The design of rudders must be so that a useful part of the rudder is still outside the wake area and can be effective in a stall situation.
Lessons leaned from the accidents in the past.
One thing you can also do in a stall is shifting the center of gravity. Like all passengers running forward. This is not very likely but could work.
I also works in a flat spin, which is another very dangerous situation you would not want to get into, because then all surfaces stall simultaneously. This is prevented usually by having the center of gravity before the center of lift by contruction and loading. Which is a requirement in designing an aircraft.
There is much more to it that has to be considered during design.
I don’t know that you will see this comment as this is an older video, but you are an amazing teacher. Your understanding and passion for aviation and the physics behind it are second to nobody I have ever watched. I discovered your channel about a month before flying my family to Florida for my wedding/vacation and binge watched so many of your videos. I felt very comfortable flying having a decent understanding of what I would watch the wings do from takeoff to landing, the sound of the engines, hearing the hydraulic system (a320) Thank you for making all of the content you do. It’s motivating to get my pilots license
Hi Daniel!
That makes me so happy to hear! Welcome to the channel.
His dog stalled out on the sofa.
yeah, this dogs are brilliant
I think he also lost power.
Lol
Or he entered a super stall just above the couch and never recovered it. lol
He was trying to activate the stick shaker.
When I learned to fly my instructor felt it beneficial to teach me how an aircraft stalls, can enter a spin (spiral dive) and recovery. The flying school had several Tomahawks each with its own stall characteristics. I got pretty good at recovery and had no fear of the stall or dealing with it as it happens. After getting my PPL I decided to do an IMC rating and was taken out by a new stand in instructor I didn't know and in marginal conditions. He wanted to do recovery from unusual attitudes and we were in marginal conditions (I expect he wanted the money for the flight). The actual aircraft we took had a nasty 'super slippery' wing drop when it stalled. He instructed me to go to 5000 feet and I insisted on 7500 feet which he felt was excessive but I did it anyway. I also said the aircraft had a vicious wing drop but he just laughed. So there I was on with a power off nose high stall and the aircraft flipped into a spiral dive, it was rare you could catch it with this aircraft. He said nothing at all. I looked across and he was frozen, I recovered the aircraft. He said pretty much nothing for the next 15 minutes then said it was a bit marginal and to go back. Never saw him again. The PPL now apparently only teaches you to recognise an approaching stall and prevent it happening, very few get to experience the spiral dive which can be overwhelming when it happens.
Suggest respectfully that you go for more lessons: spins and spiral dives are different things-with different recoveries.
Hence the need for lessons.
Happily I’m both a flying instructor, and I have a Pitts S2a, an ideal platform for such lessons!
Cheers,
Paul Stanley
That man was shitting bricks 😂
12:22 - so basically "I am a leaf on the wind, watch how I stall."
That is a scary thought.
Ok wash. Try not to get a reaver spear thrown through you
@@Demonslayer20111 going by Mentour's explanation I'd be more likely to hit the ground first :/
That. was. SO. INTERESTING! I never thought about the fact, that the aircraft's design could either stop or even worsen a stall. And now I finally know, what those little metal plates on the wings are (the vortex generators)! I was about to say, that the swept wings, trijet design sounds like a terrible idea with the new information, but I'm happy to hear about all those counter-measures.
Thank you for the excellent video!
There is a type of stall an aircraft can get into which is almost impossible to get out of? Wow, never knew until now
On this channel I always try and teach something new!
There's a few; T-Tails can blank their elevators with their wings, and planes with perfect centre of gravity can flat spin with no ability to correct.
@@TheEDFLegacy Uähh... Flat spins, this is what i'm afraid of! I do some glider aerobatics and sometimes i spin the glider, the SZD-59 for example, spins realy nice. But a flat spin, this is pure horror!
@@TheEDFLegacy And not just tails. In the trijet days, sometimes the inlet for the rear engine would fall into the aerodynamic shadow of the plane, rendering it unable to perform. If I am not mistaken, Gulfstream made the tails on their jets taller to avoid this over the years.
Yeah, the bathroom stall.
When can an aircraft be stalled? I was taught like you, at any airspeed and in any attitude. Great job Sir.
Turn to tight and the inner wing will stall before the outer, this is why pilots are taught let it slip around turns at low level rather than use too much rudder :)
A pilot gets into a super stall.
Quickly UA-cam’s how to get out of one
Finds out he’s totally screwed.
This showed up after i looked up the pulova 621 cvr. It was a super stall and you can hear the pilots panicking and screaming as they are about to hit the ground
@Homo Quantum Sapiens Ah those people who never read the manual!
@Homo Quantum Sapiens I wish I had such a great sense of humor as you do
@@AngelCanseco1 I don't know anything about this..........was it a happy ending? ....
Stephanie no, horrible screaming
Absolutely fantastic video 😎✈
Thank you!!
That is what took down AF447. Look at the accident report. Mentour, you know as well as I do that a loaded A330 can't climb at 7000fpm at any altitude, much less from cruise altitude. That aircraft was pushed upwards by a strong updraft in the embedded thunderstorm line, and after exiting that updraft they found themselves high, heavy, and at a positive AoA. The aircraft then entered a deep stall which of course blanked out the tail effectiveness. Add in the fact that super-cooled liquid (not ice pellets for god's sake..) entering the pitot tubes and freezing, which of course affects AoA and airspeed. The co-pilot didn't help things by continuing to pull up, which of course aggravated the situation and prevented recovery. If I am correct, there is a slight window of time where they could've rolled the aircraft to the right, quite a lot actually (certainly to the point of discomfort or alarm to passengers not familiar with flying or upset attitudes). The aircraft could then use the fuselage to slow it down some and hopefully recover. Outside of that, anything you'd do to recover would've oversped the aircraft horribly, or outright stressed the airframe to the point of breaking things or in-flight breakup. A sad situation for sure, but an example of a deep stall, and more importantly, an example of why we do NOT fly into thunderstorms.
“This is a very very bad situation”
You can say that again - Jesus Christ, that is some scary stuff. 😱
i read that just as he said , it .
Petter, I have the perfect career in mind for you when you stop flying. How about becoming a cruise ship’s captain? You have the perfect calmness and fun personality that naturally attracts and commands attention. Just a crazy idea of mine. Safe skies my friend.
Love the pooches in the background xx
Your relaxed pooches help create a soothing atmosphere for the subjectively tense and technical presentation of aviation mishaps.
The depth of your knowledge is breathtaking and fascinating. Your content is too good for the usual over dramatic tv programmes I have seen. Amazing. You have a calming and respectable manner, totally impressive. And you are a fellow ginger!!!
Depending on the aircraft and load, you could have 50 passengers run forward, that's be a significant enough weight shift.
On a much smaller scale, this worked years ago for two fellows who got a Yankee into a flat spin, they had to open the canopy, stand up, and lean forward over the windscreen.
They did WHAT
@@232K7 I kid you not.
Link?
@@matejlieskovsky9625 You're not going to believe this but occasionally there are no links to things that happened well before the Internet.
As well, I once read a verified report of a Globe Swift (IIRC) that had a propeller blade depart and shortly thereafter the engine followed the propeller's example. The pilot was able to regain control during the ensuing loop and successfully got the aircraft on the ground intact (or what remained of it).
I once, by virtue of faultless stupidity, managed to half snap roll a Cessna 150 upside down at no more than 50 feet off the ground. I did not crash, and went on to a long career of less stupid aviation. I have no link I can send you but it did happen.
I'm a year late but I have to say, I love the way you write. It is very entertaining and to the point. I would imagine that people like listening to you speak irl. :)
Absolut lysande. Jag kommer ihåg tell - tales från den tiden då jag seglade, vilken fantastisk väg att visualisera luftflöde!!!! Detta var mycket bra.
Doing stalls and my first solo are two of the most memorable things during my PP training. Third would be first solo cross country. Practice stalls in a 152-172 Cessna
a were quite exciting. Great video, blue skies!
I read the news about the Brazil crash, saw the term superstall here and there and arrived here for knowledge. Thank you. May the souls in that Voepass ATR and their loved ones find peace.
My wonderful nephew who is still training to be a pilot, took me for a spin in a little Cessna and once high up in the air, he stalled the plane. My life flashed before my eyes as I saw the tiny houses below me. I love my wife more than ever!
he "took you for a spin"
-well that can be dangerously misinterpreted
Adorable and warm personality of this pilot makes me watch all of his content even though I’d never wish to be any kind of pilot whatsoever 😊. Great stuff, kudos!
In before I get notification:)
Great video btw.
Also mad respect to experimental pilots who try to get the new aeroplane to all sorts of unfavourable conditions such as stalls to see how it will behave.
Indeed, deep stall was discovered on the BAC 1-11 after a fatal crash during flight tests, and a number of other aircraft have crashed during flight testing due to deep stalls.
yeah i'll just enter a flat spin to set up procedures to get out of it if I'm not completely absolutely without question totally beyond any meaningful help overwhelmingly (duck)ed
You mentioned the BAC (then Vickers) 111 which had the rear mounted engines and which crashed through a super stall back in 1963. I was an air cadet in 261 Guildford at the time, and one of our officers worked at Wisley and got us an air experience flight on one of the development 111s. This was only a few months after the tragic loss of one of the aircraft and all the crew, through the super stall that you referred to. There were about 20 of us and when our coach drove onto the flight tarmac we could see a half dozen or more 111s with rocket motors fitted, presumable for propelling the 111 out of the super stall and enable the continuation of the test program. As a kid of course , I didn't realise the full impact of what we were doing and didn't worry much about it. Today, as a retired teacher, I am somewhat horrified by it all, especially when I found out recently we were doing some of the same tests that the crashed 111 had been doing.
There was a large tank of water in the centre of the aircraft and they were pumping the water from end to end of the aircraft to test the auto pilot's response to the shifting of the centre of gravity of the aircraft ( Centre of gravity used correctly here, by the way.) And either to keep us amused, or because they wanted a stronger effect, they had us running from end to end of the mostly seatless cabin in conjunction with the water pumping!! As I say I am somewhat horrified today!!
I would just like to add that the crew who gave their lives in the crash enabled flying to be made safer for all the rest of us and I hope no more flippant remarks are made here.
Ive stalled out my planes in IL2. Friggin terrifying stuff, even in a video game lol. I got decent at recovering. Engine to idle, counter rudder, point the nose down and dive, gain speed, engine to max power and pull out carefully. P-51 loved to stall on me alot.
P51 was the first plane with laminar flow wings. It was the secret of its huge range (=low drag) but a real problem when the flow ceases to be laminar ...
That aircraft with ribbons attached to the top of the wing provided a really good visualisation of the airflow, and the turbulence when the angle of attack gets too high. I'm finding all of your videos really interesting and informative. The more that I watch, the more I realise just how complicated flying an aircraft is.
The Superman symbol you used for super-stall makes it seem like a good thing when it's the exact opposite! LOL
Soviet aircraft utilized wing fences on the top of swept wings to maintain airflow. Military and aviation folks in the United States would joke that the wing fences were to keep the airflow from defecting off the wing.
Oooh, that's a good one comrade!
And technically correct
@@christhirion9474 I'm pretty sure airflow doesn't "defect" like some Soviet pilots did.
Google the Trident! I was on one when it got buffeting on approach at about 100ft and slammed into the ground with the engines spooling up. Thank God we were nearly down. Calm hot day and must have grabbed a tailwind. It was in the 60s I think returning from Nice.
I hadn't been on a flight since 2012 but I found your channel a couple of months ago after starting a new job where I was told I might have to fly around the country for work. I take wing and exit seats every time now so I can watch how the plane is flying, and also so I'm able to help if need be. Been on 5 flights over the last few weeks and it's been great knowing what every sound, action and stage of flight is.
Maintain thine low angle of attack lest the earth rise up and smite thee! I fly agricultural aircraft (Air Tractor 502 ) and we have to think about angle of attack continually because of flying steep repositioning turns all day long.
I'm sure I read "flying sheep" in that comment.
Lovely coincidence. I've published a very similar video yesterday, in Portuguese, talking about the importance of understanding AoA, while demonstrating that in flight on my Cirrus. As always, great video, fellow pilot!
"paper aircraft" love it
Love the first officer puppy bored with the information provided for passenger interest. Great video!
Great video Mentour i enjoyed it, i remember when i had a flight in a Piper PA28 and the pilot did a stall recovery demonstration it was fun! I love the captions you put on Patxi too, have a great weekend my friend.
Thank you! You too!
I'm transitioning to a PA28 next month. I hear they have very nice stall behavior, at least the older models without any wing taper.
Your relaxed pooches help create a soothing atmosphere for the subjectively tense and technical presentation of aviation mishaps.
Hi dear Captain,i never could be enough greatful for all the pertinent content you brought us mainly in addition to all that regards aviation ,you are helping us to set up a succesful mindset ,a way of thinking and visualizing things from diferrent perspectives to get the right step to be held.thank you very much 🌹🌹
This happened to me under similar circumstances. I simply induced a spin by throttling down and applied hard-left aileron. After a 90° bank action, I slowly throttled and applied opposite aileron and was back to enjoying my day
I feared stall and spin training as a student. Much later I practiced these with a huge grin on my face. (not near the ground though!)
Stalled a glider at low altitude when landing - once only. That was a nervous few moments! Paid more attention after that :-(
Mentour pilot, this was a great video, thank you for all the brilliant explanations. I know that the Max has now become a taboo but it's impossible to think of stall nowadays without thinking of the Max. So I think that the logical conclusion to this subject is another video specific for the Max, explaining the aerodynamics involved in that design and the role of the MCAS. Thanks.
Paulo Gaeta Good points! IMO the MCAS on the MAX still hasn't been properly explained.
The stick pusher sounds a little like MCAS! Love your pronunciation of stabliser!
Richard Reed There are similarities, which Boeing were denying, because a stick pusher requires more certification changes, and type specific training.
@@gordonrichardson2972 very true. I bet they wish they could turn back time and pay out for that training now!
Videos like this remind me how crazy combat aircraft and pilots can be. There is a report from Vietnam where an F4 pilot intentionally "detached" from flight into a tumble to shake a chasing MiG. He then recovered behind the MiG and shot it down. The fact he could do that, recover, and not rip the wings off is insane. Especially in an era with very little computer assistance for the pilot.
Yassss! Another video my day has been made! Love ur content Petter! 👍👍👍😊😊😊
Thank you!! I’m so glad you like it!
No, thank YOU sir. Your the absolutely fantastic one here! 😊
As a new fan of yours... this pops up! I'm Not an aviator... but am a retired Gas Turbine Mechanic from the Navy!
Sooo looking forward to this video!
So much so... I have to.comment before watching! Lol
One of the benefits of having a set of canard wings, they stall first dropping the nose before the main lift wings can stall.
I need to research this more.. It certainly would makes sense in a logical first-pass. I presume increased drag is the rational behind their lack of use?
@@topiasr628 Canard are aerodynamically complex and take a lot of careful design to function properly. In general the benefits are not seen to warrant the increased design / construction / maintenance costs.
That’s so funny I was right in the middle of this topic on my ATPL CBT when you uploaded. Nice supplement to it. Cheers and safe flying.
During a super stall, could you regain flight by having the passangers flocked to the front of the aircraft changing the center of mass?
lol stay in school kiddo
Theoritically you can do this. Practically you will have to get the passengers quickly moving up a slope in rough conditions without panic. Quite a challenge.
I, as a passenger in this situation, would be willing to try this.
@@jimbeaux4988 It is not so much about will. more about implementation.
@@roichir7699 "Free drinks in first class for everybody!!!"
Love your videos! Non-pilot aviation buff and 75k+ miles/year business traveler. Thank you for sharing your knowledge & expertise from the cockpit. 🙏
Would dropping the gear and/or flaps help you to overcome a deep stall? My thinking here is that adding drag below the aerodynamic midline and behind the centre of lift might help to pitch the nose down.
A very good video about deep stalls. I think it would be good to mention that most modern airplanes use wing "washout" to ensure the wing stalls inboard first and wing tips last. The wing structure is such that the angle of attack at the inboard end of the wing is greater than the angle of attack at the wing tip, ensuring that aileron control is maintained as long as possible in the stall. Also, while the 737 doesn't have a mechanical stick pusher it does have a somewhat equivalent system called "Feel Shift". As the airplane approaches a stall the first warning to the pilot is the stick shaker. If the angle of attack continues to increase the Elevator Feel system will increase the column force resisting the pilot's input thereby pushing the column in the nose down direction.
Excellent presentation.
However, I would add that any aircraft can potentially be inadvertently deep-stalled under unusual conditions such as abrupt environmental turbulence, versus "typical" aerodynamically induced aberrations.
The condition may also not meet the test of the classic stalled condition - with a stick-shaker - as opposed to a vertical 'inertia,' rather emulating a vertical bow wave.
The B-737 100, 200, 300 (presumably the 500 series) are known to encounter a loss of elevator authority during moderate-heavy icing conditions; due to disturbed airflow from approach flap settings, coupled with the icing buildup on the horizontal stabilizer. I've personally witnessed 'square' ice on the horizontal stabilizer.
Altitude and time permitting, if possible, I'd encourage a thought to turning off any power limiting features in an emergency, so as to maximize "survival thrust'" - damn the engine replacement cost. Whether you accelerate through the 'condition,' or use engine differential thrust and/or flaps and landing gear to maneuver/break out of the 'condition,' the awareness of the possibility and early recognition are paramount.
In the case of the typical airliner, it's possible to encounter such pertinent 'onset' conditions due to an abrupt higher-than-normal air temperature deviation during cruise or climb, even without vertical gusts from thunderstorms, for example. The FMC and other automated features may not give timely clues or 'solutions.'
As an indicative but extreme example, in November 1968, in Alaska, an F-27 encountered a vertical 'sheer' in clear air at 20,000 feet - calculated by the NTSB at 29Gs. Its impact was far more vertical than horizontal.
In aviation, anything is possible - and probable.
Indeed. It is a popular and dangerous misconception which seems to be taught that "only T-tailed aircraft can enter a deep stall" and I even noticed one experienced pilot commenting on the AF447 incident that "the aircraft was not in a deep stall because it is not a T-tailed aircraft".
Any aircraft can enter a deep stall if the horizontal stabiliser is stalled in addition to the wings. I'll repeat that.
Any aircraft can enter a deep stall!
The combination of a swept-wing and T-tail is most susceptible to a stall, due to the poor stall characteristics of the swept-wing as described here (alongside the shift forwards of the centre-of-pressure as the AOA increases on most wing designs, not mentioned here) and the turbulent flow over the horizontal stabiliser reducing elevator authority. However, any T-tail or swept wing is susceptible to a deep stall and even a non-swept wing craft under the right conditions could experience a deep stall.
As Ralph mentioned, vertical sheer/extreme updrafts which result in an abrupt change to the angle of attack can in theory stall the horizontal stabiliser and it is possible that this is what was encountered by both AA8501 and AF447 since both planes climbed beyond their performance capabilities at high altitudes, suggesting that they encountered updrafts which resulted in a high vertical speed (this is mentioned in the reports as a possibility but NOT directly linked with a necessary change in the AOA). This type of stall is doubly dangerous as the abrupt transition from normal flight to a deep-stalled condition would not result in a stall-buffet as the airflow would detach from the entire upper surface of the wings and canards at once. This makes the deep-stalled condition even more difficult for pilots to diagnose. We may never know if AA8501 and AF447 were in deep-stalled conditions, as the pilots flying failed to recognise the stalled condition at all until too late. The response of AF447 to side-stick inputs and rudder commands by the FO during the final seconds of flight indicate that a deep-stall was probable and had the SO pushed forward on the stick it may have had no effect whatsoever, but since he didn't we can only speculate.
Nevertheless, it seems shocking to me that so many pilots believe the myth that not all craft can enter a deep-stall. Modern aircraft are returning to designs where the body and nacelles produce a significant fraction of the total lift. In a stall-condition, this lift is a stabilising factor which helps to prevent rolling and yawing motion during the stall which could lead to a spiral descent. However, in a deep-stalled condition, this lift can stabilise the craft in a gliding descent with nose-up attitude, keeping the horizontal stabiliser in a stalled condition. Tricky business...
I agree with what you are saying. Flying should be illegal. It’s just too dangerous
Hello I never learned stalled wings that way. I learned from Lee Mercure that was one of the original creators of aviation in the USA and the world that, YOU LOAD THE WINGS AND UNLOAD THE WINGS . That is the correct and elegant way to explain a stalled airfoil. Saludos aviador
7:47 stalling near ground: „That’s a really really bad day“ Most certainly would be!
He is too good. Thanks for noticing.
When I go to the practice area and play, uh, practice stalls I want to be at least 3000' AGL.
747, no. Just me?
Low and slow make's the warning lights Glow 😏
The cushions are the icing on the cake. Nice vids mate. Thanks
I would love to see you try getting out of a super stall in the flight simulator.
Best pilot ever. Scary stuff and you maintain such level of professionalism. Your dog is either super disciplined or super lazy.
Very informative! I loved the visual👍
Great! I’m so happy you liked it!
I've been so lucky to find this channel, which has absolutely eased my fear of flying....And then I found this...
This video increases my angle of attack
dragonex814 then you will stall from the bottom to the top ....stall to Mars or the moon
Some VC10s had twisted wingtips to give lower angle of attack at the tip, meaning it was less easy to stall the tips, and so the aircraft could fly slower and also higher than the unmodified versions.
This ties in well to coffin corner
I am working on my Private Pilot's License right now.... you do such a great job explaining things! So many of your videos have helped me out. Thanks!
The deep stall is very well explained in this video. Congratulations. On the FlyJSim Boeing 727 for X-Plane flight simulator, with Ultra-realistic flight model, the "Deep Stall" is very well simulated. Stalling a B727 T-tail will get you in an unrecoverable "Deep stall" in no time, with no aileron, rudder, elevator and/or engine control. Unless the deep stall occurs at at 30,000ft, and the plane drops 20,000 ft.. it may by chance get into an attitude, that may allow to recover... and that's a maybe. It's nasty. Otherwise, very aerodynamically sleek, super-clean, fast and pleasant to fly T-Tail. Just don't stall a T-Tail because it will show you it's bad side, and will bite you!
Add to this that when you stall the wings and stabilizers you also stall the engines… So it's even less possible to recover from that.
I'd sadly skipped this one, thinking “Aviation 101”….but am So Very Glad i finally watched! This is a must see! For a host of reasons:No Spoilers, promise. (Graphics are just too much fun!)
13:45 “flow-wise span”
means: span-wise flow - air movement parallel to wing’s axis.
Im not an pilot, just playing flight simulator but still think it's exciting to learn :-)
Love the doggy translation captions
Looking at the tapes on that stall test footage is quite spectacular. And, really scary for me (being a laic).
Hi Mentour. Very interesting video (as usual). In the Danish Air force we use to fly the Draken, and when they were phased out, at number were sold to an American Flying School - if I remember correctly - as this airplane was actually able to recover from a super / deep stall (if they had altitude enough). I am not sure exactly how they did it. I have not been able to find any videos here on YT, where you can see it . Cheers Adam
A great lesson indeed. Fortunately passengers don't realize how complicate and tricky flying can be. Avoiding stalls is an absolute must!
"The aircraft will fly like a leaf ... to the ground."
A big, unwieldy, fuel-filled leaf.
The second sentence was intentionally omitted. I'll reinsert it for clarity......
"The aircraft will fly like a leaf ... to the ground. It will then act like a bomb."
What a great channel for any nervous flyer. Thank you Mentour Pilot. Very smart guy.
Maybe the MCAS system is just a fancy name for the computerised electronic stick pusher they snuck into the cockpit without advising the crews!
GaryNumeroUno I have heard that assertion, and it has an element of truth!
I think you'll find that every aircraft with a stick pusher, the crew were advised of its existence and how to manually override it (pull harder) and cancel it, as part of their type training.
cr01 Precisely the difference from MCAS.
A friend built a model 1-11 some years ago. While at the design stage this issue was discussed. One interesting idea that was raised, but not implemented, was the addition of a small explosive device on the cockpit roof. Designed in such a way so as not to damage the airframe, but powerful enough for the blast to kick the nose down. I wonder how much force would be required on a full size airliner?
Deploying a drag parachute from under the aircraft rear was also discussed.
But I'm sure the builders have gone into this more than we have and I do not see any of these fitted.
If I recall from my aerodynamics class, deep stalls tend to affect T-Tail configurations more, because the slipstream created by the wings renders the elevators useless.
Les Turner correct, on aircraft that have the horizontal stabilizers behind and slightly above the wing (the sheer majority), upon any major upset, the stabilizer will be freed from wing wash. If i’m not mistaken, however, the horizontal stabilizer can itself stall, rendering the elevator’s up authority ineffective. Note the Saab 340 and Metro’s that have the ‘cruciform’ tail. Can be deep stalled, at a higher angle than on a low mounted stabilizer, yet far lower than a T Tail (the purpose of which is either to clear tail mounted engines, or clear turbulent and highly variable prop blast.
And if I also recall, the propwash won't be hitting the horizontal stabiliser then either. But, I'm not 100% certain
Upsetraygun2 T Tail in deep stall? I would doubt it, the prop wash would still be blown roughly parallel to the engine’s axis, though would also be blown backwards with the still forward speed of aircraft, though the differental of prop blast speed to rearward speed would be so high, would likely pass behind the aircraft well below the stabilizer. The advantage of propellor over turbofan engine is that a turbofan can get compressor stall, and even be completely blocked, by high angle of attack at low airspeeds, a propellor however, being completely unconfined, really doesn’t care from which direction the air is coming, given that it is sitting completely unconfined, in it.
@@jaysmith1408 That's what I meant sorry bad phrasing.
With the horizontal stabiliser directly aft of the prop, such as a c172 for example. You should be able to increase your throttle to create lift over the elevators.
Where as with T-tails you can't.
Upsetraygun2 no worries, if i’m not mistaken, there is an advantage to having the stabilizer in the clear of prop blast, clear undisturbed air, less blown debris, not behind any fuel, oil, ice, other miscellaneous parts that have grown tired of being attached to the aircraft. However, primarily, this is disputed for extra weight, control complexity, and as you said, does not have the advantage of prop blast. The downside to the C172 method, is similar to the issue with the lockheed electra’s wing. The electra has massive propellors, and a fairly small wing. On good days, the propellors spin, effectively creating its own lift. On bad days, the propellors create drag, no thrust, and highly turbulent air, where the aircraft would almost fly better with the entire engine missing. Once the propwash is gone, so is the gross majority of the lift. At this point it’s the Ford/FCA/GM debate, six of one, there are different methods, they all work, depends on the application. As well, as demonstrated with flow separation, the advantage of being downstream of the propwash, is just that, only when directly downstream, minimal angle of attack. At a higher angle of attack, the stabilizer will no longer be downstream of the propellors, the flows from the propellors, and over the stabilizer, would be parallel, and adjacent.
Fantastic dog's thinking... Adding happyness to the already number one video!!! ALL the best from Brazil...
Yay! 727 Mentour Edition!
Hey P..., just out of curiosity at first and then interest due to the catastrophic loss of life when in a Crash , I have watched most of your videos. I am an Octogenarian so no more air travelling;now
Since engineers are fully aware of potential super stalls or deep stalls one would think they would create a new control surface that appears in these dire situations.
Instead of only horizontal control surfaces in normal flight. Maybe they'd be a button that now activates a pop out Vertical control surfaces that provide pilots ability to get plane in a high left or right bank to get nose to drop and regain needed airspeed.
Almost like a large rudder but aligned downward instead. Instead of a yaw one would get a roll instead with ailerons are in turbulent air & no longer effective.
This new Emergency Pop out veritical type rudder control surface needs to also be forward to be out of turbulent air.
probably too expensive or wouldn't be useful enough to justify fitting them
Yup, 10/10 for these videos. Well done MP. OK, say a super-stall at 30K feet? Dump fuel from ONE wing? If there is time, then one wing will drop, and also asymmetric drag, which might get the nose down, and eventually, speed up?
I have an audible indicator in my aircraft with a boston accent... It says REEEHHHHTAHHHD REEEEHHHHTAHHD or
WIKID LOW.. WICKID LOW!
Eli Wesley haaaaaa🤣🤣🤣!
I have one with valley girl accent too... Liiiiiike i think wee R gonna totally stall!!!
@Kyros - actually, it wocks
Welcome to British English
Eli Wesley Ya got a stall goin on ofver dare... pull up doont ya know!
@@cranjismcbasketball2118 push down, push down
Without any doubt whatsoever, this has is the best presentation you have given!
"Use stabilizer trim, make sure you don't use too much" I think he is talking to the MCAS system hahah
Jordi Tribo Everything about MCAS on the MAX touches on points addressed in this video, longitudinal stability, horizontal stabiliser, and elevator effectiveness.
Gordon Richardson And undermounted engines that are too large and throw off the center of gravity
Can't help but think the "sticky pusher" could have been a better alternative to the MCAS, but it would have required pilots training...
@@stone-hand someone tried to save cost then...... 🤔
@@roku_nine - Not so simple, much more roundabout and sneaky than simple penny saving.
Using a sticky pusher would have made the 737 pretty much a different aircraft, in terms of certification process.
It meant adding years to the MAX time-to-market, leaving too many companies tempted to buy the Airbus A320 NEO, which could be an issue down the road as most small companies tend to use planes from a single manufacturer, because it simplifies logistics.
So, once an Airbus is inside a company...
Boeing was so much in a hurry that they went with a botched automatic system that used a single AOA sensor, something that they likely knew had to be re-implemented down the line - as they did with a somewhat similar system used in the NG - but at the moment sped things up, as a single sensor system could be certified much faster.
We all know how that turned out.
If Boeing had accepted the inevitable delay and just went with a dual-input MCAS from the start - i.e. the fix that they are developing - we'd would all be just in awe of how gorgeous the MAX looks with his badass big engines...
Oh, that reminds me of my old sim days. Those deep stalls were scrary when flying a f16 due to design instability. The procedure was to use a switch to override some precautions and then u have to pitch up and down in the same rythm. When upside down, it's almost impossible to recover.
The Trident was a high T tail aircraft and could super stall. The only way to get out of one was to fire a parachute out of the back to lift the tail which was done on initial proving flights. A superstall was the cause of the Staines crash near Heathrow in 1972. Someone retracted the leading edge droops ( now called slats ) which could be controlled independently of the flaps on the Trident. They had all the warnings but ignored them and cancelled the stickpusher. Incredibly Tragic.
Steve; Were those super stall recovery parachutes installed on production passenger carrying Tridents or were the pilots just told "Don't do that!"?
No, they only used them one time AFAIK at Hawker Siddeley during the proving phase of the development.
I knew someone who was involved in the testing.
One of the saddest accidents I have read about. Because of the lack of C.V.R, we can only guess as to who exactly retracted the droops. Due to the probable incapacitation of Captain Key, the aircraft did not reach flap-retraction speed, and the lack of visible cues and experience of the 1st and 2nd officer did not help either.
@@Vincent_Sullivan
The Tupolev 104, being based on bomber, had a parachute to help it stop as its brakes were dire and had no reverse thrust.
It also had swept wings and wing fences to stop the lateral air drift...
Huge flight enthusiast, not a licensed pilot. I am in the simulator daily though. The other night I was practicing stall recoveries from the safety of my house. Was 20000 feet off Mount Blanc middle-of-the-night IMC in a citation. When into a super stall. Dropped 14,000 ft before hard right rudder finally began to get control of the aircraft. Leveled out at 3500. With no formal training after watching this video it makes perfect sense to me as to why I was completely helpless no matter what inputs I made
The stick pusher sounds similar to the MCAS
It is pretty much similar, but much better executed
I love this channel. I feel like I've learned so much about aviation. I hope one day to fly on a plane you're piloting. Gotta visit the EU.
"Look! Up in the sky! It's a bird, it's a plane falling like a leaf, it's Super Stall!"
Thank you for another great video. Greetings from Poland!