We achieved spin resistance by tailoring the airfoils across the span of the wing, specifically by giving the outboard portion of the wing higher maximum angle of attack capability. This was not easy and required CFD, wind tunnel testing, and 3 full scale wings flight tested on our POC airplane. The slope of the wing lift curve does in fact level out from 20 to 30 degrees alpha, but stays positive to yield positive roll damping up to max angle of attack.
The basic premise of spin resistance that NASA developed is that the outboard portion of the wing never stalls, thereby retaining full roll control while the majority of the wing is stalled and the airplane is descending. ICON did not limit pitch control at all to achieve this. The A5 has the same pitch authority we desired for good handling qualities at all CGs before spin resistance testing even began, and we didn’t need to reduce it to achieve spin resistance.
Icon: hey u get to be a test pilot for spin resistance! Pilot: oh wow, i can't wait to fly the safe and steady Icon A5! Icon: ummmmmmmm no u get to fly a c-150 at the ground in a spiral
That's really cool visually. You can see how the inside of the wing is designed to stall first while the control surfaces on the outside maintain laminar flow.
Beautiful design. Beautiful engineering. I hope you sell a ton of them. Also hope you make a non-folding wing version so it can be cheaper so you can sell a ton more!
I have an Icon A5, but radio control. The RC version of most planes act similar to the full scale versions, as mine does. I can definitely stall it, but I also have more throw on the controls than the full size version. The aircraft is very controllable, and one of the "tricks" I like to do is to get it in a full on tip stall, and pull it out after falling about 50 feet. It makes sense what they are saying, I have control even in a stall, no doubt. The RC version is definitely not a trainer
Impressive and thank you for taking the enormous trouble of designing specifically to counter spins ! On another note, could I ask how the top of the tail has been tested for strength - having the forces all the way at the top end would put enormous strain and torsion force on the boom fuselage leading to the tail. thanks
I just read on your website that new orders wouldn't be shipped until 2017... and I actually felt disappointed. As if I could even afford one! But something like this just inspires my imagination, makes me realize I want to do more "out there". You can't put a price tag on that, but someday I'll own an Icon. Preferably the A7 (two generations from now).
Hexagonal dimples or longitudinal scallops on top of the wing would create low pressure pockets as the airflow ramps over them. This would lower stall speed, allow greater angle of attack and increase lift.
I loved spinning C150 and C152s gives confidence. The wing low slip to land is also a confidence maneuver for the ones that come to high on final and still want to make the RWY a great breaking the speed off maneuver dirty flying, use the uncoordinated flying only while steep descending, level off coordinated and final check for airspeed, X wind consideration etc, wing low or grab into wind and rudder lineup, my favorite is the wing low landing in Xwind. On water beware not to tip the wing into water.
The "Ercoup" [sic] (spelled Ercoupe) earned its Type Certification in 1940 by the now (highly) obsolete CAA. Its "characteristically incapable of spinning" behavior was achieved by robbing the pilot of any rudder pedals or independent yaw control. ICON's claim was that the A5 is"the first production airplane to be designed to meet the FAA's full-envelope Part 32 Spin Resistance Standard." This claim is 100% correct. Just calm down and enjoy an awesome feet in engineering and a sexy plane.
Not sure if I like the fact the rudder no longer responds in a full stall. It seems a bit strange that you can give full rudder in a stall and have the plane continue in level flight. Normally, the rudder is the one control that works in a deep stall.
Looks like the reason for the stable stall is in part due to the tail high elevator is rendered ineffective being in the slipstream of the main wings and shadowed from the airflow. The question is then, how much pitch authority do you have to get the nose down in order to resume safe flight from a stall condition.
The tail is right behind the prop. The main spin resistance design ques are found on the wingtips, but if the slipstream has something to do with it, adding power should give you full elevator authority.
I used to ride shotgun when my buddy would practice spins in a rented 150A. I always needed him to count each spin or I'd get nauseous. I had absolutely no problem doing a 0 G or any other type of maneuver that would make most queasy, but doing someone elses spins with no control on my end made me wanna launch, even after doing it for months. I never could figure out what my problem was there. As a side note, the aerobatic he'd practice in area was real close to his home, so we have pics of his dogs looking up at us as we're doing spins towards them. We always thought the dogs heard the odd engine noise and looked up thinkin' "that's gotta be daddy and his friend".
A safety feature I tought for passenger jets was 200 ejection seats when the plane is no longer flyable ( stupid idea anyway but with a good intention) but these airplane safety features makes my jaw drops. Why this technology hasn't been used in airliners yet. Parachutes have been used in space shuttles since long time ago. That could give to us...the passengers some peace of mind and stop being so worried about some plane failure that can makes us end up in pieces on the ground.
Surely canard aircraft with the smaller front wing at a higher angle of attack than the rear wing also prevent stall/spin circumstances? Apart from that, way to go...
I know this, my RC ICON A5 does spin in a turn with no power. The RC version likes to have power in a turn. Other than that, the RC version is so much fun to fly.
A stall occurs when (and only when) the angle of attack exceeds the critical angle of attack. This is about 18 degrees in this type of aircraft. As the aircraft slows the angle of attack is increased to generate more lift and keep the aircraft flying. At that critical angle is exceeded, when the lift reduces dramatically and drag increases. The problem is NOT slow speed, it is that the critical angle has been exceeded, though in this case it IS the slow speed that has required the high AoA.
Not every stall results in a spin, that only happens when one wing stalls and the other does not. Notice in the video they put in full right rudder, so the left wing is going a little faster than the right, which stalls first. Cessna said after the first Skycatcher crash that they went back to the wind tunnel, redesigned the vertical stabilizer and made the plane more spin resistant. Then they crashed another one the same way. Now they say they really have it fixed.
To everyone at Icon, my heart goes out to you and the loss of Jon and Cagri. My condolences to you, and the family of these two fine gentleman. Jon will go down in history as a tremendous historical asset to aviation. All the best to Icon. Amazing company, amazing family.
Watch knees from 2:13 in video..control inputs are different. The 152 has full right rudder, the A5 has NO rudder input until after the stall. If the max rudder deflection is what is shown in the video, then the cross-wind landings of the A5 must be extremely limited. I'm all for the A5 going for FAR23 with no waivers. Let's just be fully truthful. Can it meet FAR23, stay under LSA weight, have swing wing and amphib gear? I fly an LSA amphib and know what a challenge that is. -Ken N52596
Interesting to see that the root has stalled but the tips still have the airflow to maintain control.Funny seeing in rudder and full back stick and still staying rock solid in the air.
Hell, some of the very earliest Aeroplanes were almost unstallable. One example (but not the only one) would be the 1910 Bristol Boxkite. Those used a forward cannard set at a higher angle of attack than the wing. The cannard stalled (and dropped) before the wing would, dropping the nose and increasing airflow over both cannard and the wing. I suspect Siggen (see below) may be on the right treack and Icon have figured some way of doing something simialr with the tail ... that said its has me baffled how you'd do that with a tail.
A colleague pointed out that the Eurocoupe also claimed to be Spin-Resistant: See its wikipedia page: 'The Ercoupe was certified by the Civil Aeronautics Administration (CAA) as "characteristically incapable of spinning." '
Since you are familiar, why don't you explain. It seems reasonable to think that if the vehicle loses speed, it will "sink" as the air is no longer passing through the wings at speed and helping its structure move up or stay at a constant height. Please expand on the issue if you can. Thank you.
Yes stall and spin and stall is a importent feat to master, for some who didnt hear they say that this plane is a Good plane to do training in is in fact stall and spin training in a safer way, i know the training is hard and stressfull on new pilots and can be realy scary, but i is also a dangerus job for the instructor`s to teach a new pilot to recover from a stall and spinn. to the hole team of A5, Amasing jobb!
I was clearly talking about the C152. The plane is spinned on purpose (banking right and right rudder), while the A5 only gets right rudder. By banking the C152, you are reducing lift, and therefore, with barelly any lift, any rudder input will therefore induce a spin immediately, whether on an A5 or a C152.
I'd love to see more stall resistant designs...but for a different pilot certification category. I fly airplanes that are not "spin resistant" in prolonged, deep stalls, controlling heading, avoiding spins, and while rather "in control" of the event. These airplanes do what a well trained pilot asks of it - I like that about them! A lot of pilots (and CFIs) rely on crutches to get by with their lack of training and exposure to the full envelope and then one day, it bites them (or their students)
Yep with 300 hours in 172'a and many hours in other in other aircraft it is a deliberate act to spin them. The stall (and 152 stall/spin) in the video is only straight and level and power off where most GA accidents stalls (Over three years accident study) happen in low altitude turns, then take off, many over weight or out of G of G. Icon have also submitted a weight exemption of 250 pounds to the FAA sighting stall safety. The folding wings also contribute to extra weight so stall safety?
Is it still spin resistant with the engine stopped? In my head the draught from the prop over the tail would make a significant contribution to its post-stall controllability. Still cool though, like electronic stability control for planes.
I want 1, but a 4 seater & at least with 500-700 miles or at least a NYC 2 Florida travel time distance capability, but i guest even at top cruising speed (120mph) it would take about 7 & 1/2 hrs from NYC 2 Florida. still love it though.
Yeah, it has maybe two thirds of that range, and only two seats, and less of pretty much everything (except water landing and maybe stall resistance, based on their company video) than a Cessna c150. Also, it costs well over 10x as much.
Want to limit stalling and reduce spin chance in any aircraft ? Fly with a thick pillow of appropriate thickness between your stomach and the yoke, or pillow between your knees if stick controlled. Other method, connect a steel wire of appropriate length between stick and dash board. I still would take an ICON. There are plenty of cool features to make it great besides just the safety reasons.
Hey thanks for the point out! I Honestly never got to the end of the video before! The lie at :37 tuned me out although I had watched through to the spin tests. So at the end of the video they weasel worded the lie they told at the begining of the video. Interesting! Now that I have heard it did you notice the additional caveats? Was not the Beech Starship the first Part 23 spin resistant aircraft? (oops!) They had to throw another caveat on there. ;) It's a shame it failed certification.
Please build something that starts and lands vertically. It's possible with hybrid engine burn+electric in ultra light aircraft, if the engine have more power for ~30 seconds (batteries).
Ejection seats in the hands of an untrained passenger deck would be far more dangerous than any potential saving capabilities they would offer. As for parachutes, larger aircraft are orders of magnitude heavier than this tiny little aircraft, the parachutes required to save this aircraft would be both extremely expensive and probably too large to actually fit on the aircraft. Even if they could fit, where would you mount the parachute that could withstand the forces as the chute opens?
I agree that they should probably shown the stall/spin characteristics with increasing bank angle. Seems that the root is designed to stall early. The outer part of the wing, which has the best ability to torque the plane into the spin, is not stalled. This probably gives the plane its low sink rate while stalled.
This looks impressive but the main question is how do they achieve it and why not do like Cirrus with a parachute system since the aircraft is so light. Performance would probably not be sacrificed. I would love to see a 4 seater Icon aircraft, I would probably buy a 4 seater.
Apparently the Skycatcher test pilots found a way, twice! I gather it was power on, cross controlled and intentional, but they were not able to recover.
Isn't that the case already? Most folks learn on 172s which have stable stall characteristics. Not nearly as far as the a/c in the video, but still far more stable than craft with higher performance wings, twins, etc. Don't people ALWAYS train on something easier? When you train your kid to ride a bike, do you put him or her on a racing motorcycle, or a bike with training wheels?
in the video during the stall did you all see how bad the tale was shaking..Im sure if these catch on were going to read about the tails breaking off the plane like an old bonanza
However the definition of a spin is not one is still flying while the other is stalled. A spin can only be entered when both wings are stalled. One is just stalled more than the other.
This is very impressive... but I’d like to see dynamic critical alfa test results, to say, accelerated stall and spin entry behaviour... As a long time instructor on GA Aircraft and having flown thousands of hours on Fly-by-Wire aircraft, I have observed and seen first hand conceptual misunderstandings on how all sorts of pilots, experience and low-time, react on the dreaded “base-to-final-overshoot” scenario. True: Not every pilot reacts the same, and many either increase bank, and/or worse, try to “cheat” believing that the rudder will solve their problem (very famous example of that was lCallsign Revlon”). Any info on those?
mate, the lead engineer Jon Karkow you can see is this video is already dead - crashed in an A5. Not the best track record for this little innovative plane..
Doing delayed recovery stalls I was doing well for 1 min, lagged behind, rolled left. 2 turns when I realized I had the rudder to the floor. Right rudder, spin stopped, 2 turns right. House, fence, tricycle turning counter-clockwise where the horizon should be. Instructor George Mejeur nudged wheel forward, I did the rest. Nose came up through horizon, said I forgot to neutralize rudder instead stepping on the right. I was embarrassed. He burst out laughing. Next week we did an hour of spins.
I'm wondering when we cross the line from piloting to just driving airplanes? How is this a good trainer if it's flight characteristics are more forgiving then any other aircraft a person will ever fly?
We now know that an Icon A5 has crashed onto the shore of Lake Berryessa, killing Icon's Chief Aeronautical Engineer, Jon Karkow as well as Cagri Sever who had been working with the company for just several weeks. This occurred yesterday, May 9, 2017. It is not yet known if the accident was as a result of a spin or spin-testing.
I left a comment here three years ago, sufficiently impressed by this aircraft. When I saw this in the news today, I was saddened at the loss of two engineers. Seemed like such a cool innovative plane, but I'm curious to know what really happened up there.
I'm not pilot (Yet!) but as I understand one of things the instructor makes you do when getting your pilots license is to educe a controlled stall then recovery. Kind of scary if the plane is capable of a flat spin no?
What's wrong with spinning? Nt buddy and I did 22 turns in his T craft over Moab. My instructor was watching in binocs on my first solo and I did 6 turns in the club Aronica. He grounded me for 2 weeks and required me to recite the rules for spins Iguana.
I applaud ICON, however, just as Cirrus failed to positively impact the safety of flight, the big issue is pilot training and judgement. Rudder limiters, outboard leading edge cuffs, etc all come with increased risk in other aspects of the envelope and even if that weren't the case, exposing pilots to planes that reward them when they fly poorly is a bad way to prepare them to fly anything else, it trains them to safely fly only that one, particular, airplane.
??? Per the ACS you still have to learn Power On/Off stalls and do them to the full stall and be aware of the spin recovery... it is still very much relevant in Private ASEL/ASES
Wow. This video has elicited an impressive number of rather boneheaded comments. I think pilots should be trained to recognize and recover from spins -- I think at least introductory aerobatics should be a part of flight training, so that if somebody finds themselves in an unusual attitude, they don't just start screaming, but rather rely on their training to recover. That said, I'm totally in favor of a design like the Icon, that won't kill somebody for making a mistake. Well done.
I am 77 years of age...and I would give my life to fly this machine......! ICON A5 I have over 2000 hrs of flying time but this is a few years back already...? You did a super JOB.......!!!
I suspect that the high placement of the tail elevator is how they achieve it. In a stall, the center of pressure will be above the center of gravity, and the aircraft will subsequently stay upright. The C-150's tail elevator looks to be placed at or slightly above/below the center of gravity, rendering the aircraft inherently unstable in a stall. The A5 acts like a human under a parachute, or like a badminton shuttlecock, they right themselves in a vertical fall, since their centers of pressure is above their centers of gravity
Well, yes & no DJ787. How *much* performance is lost in the trade for safety - and where its lost - is a legitimate consideration too. For instance, if the trade was to up fuel consumption that would have a safety negative implication too (you don't want to run out of fuel). Now, you could with some fair grounds argue 'Pilots should have more sense than to run out of fuel'. But then, they should have more sense than to stall too. Reality is the dumber ones do both. That said, what this company is doing looks promising .......... Just hope that if there are drawbacks the 'safety at any price' brigade doesn't get to shove it down everyone's throat.
Siggen, Actually, The T-tail configuration is more susceptible to uncontrollable stall characteristics. Just look at the Beechcraft Skipper and Piper Tomahawk for example. The way the Icon's wing is shaped, With a shorter root chord and longer tip chord, as well as a higher root incidence angle than tip angle, ensures that the root of the wing stalls well before the tip of the wing. It essentially makes it almost impossible (very difficult) to stall the entire wing at once. The loss of lift during the partial stall causes the nose to automatically drop before the tip airfoil reaches it's critical angle of attack. This technique is called aerodynamic twist and is commonplace on most aircraft. It is just utilized much more extensively in the A5.
It is a nice aircraft, the accidents occur when people think they can do more or be maverick. It is a tourism aircraft that I would buy soon If I had the possibility.
I absolutely agree with you, but the plane is still a decisive point... I mean, if your plane got the reputation to be unstable on stall/spîns, even with the best training in the world, it does'nt change that much...
They state up front in the video that they deliberately stalled both aircraft. They're not trying to fool anyone. While some of their claims may be exaggerated, they have built a very impressive little aircraft.
But it seems none the so called experts are engineers. The spin resistance appears to be due to the wing design vs limited elevator travel. Look at the streamers on the wings during a stall the main parts stalls but the ailerons are still in laminar airflow allowing control to be retained. This is likely due to some serious CFD work. CFD modeling did not even exist when the ercoupe was designed so this is a far more advanced concept.
![I.N "HALLUCINATION" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/n5B5q1Hwt_U/mqdefault.jpg)
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We achieved spin resistance by tailoring the airfoils across the span of the wing, specifically by giving the outboard portion of the wing higher maximum angle of attack capability. This was not easy and required CFD, wind tunnel testing, and 3 full scale wings flight tested on our POC airplane. The slope of the wing lift curve does in fact level out from 20 to 30 degrees alpha, but stays positive to yield positive roll damping up to max angle of attack.
Good, so if engine fails you can still land it better than a parachute is it?... N how much it cost what hight it can go upto
The basic premise of spin resistance that NASA developed is that the outboard portion of the wing never stalls, thereby retaining full roll control while the majority of the wing is stalled and the airplane is descending. ICON did not limit pitch control at all to achieve this. The A5 has the same pitch authority we desired for good handling qualities at all CGs before spin resistance testing even began, and we didn’t need to reduce it to achieve spin resistance.
Icon: hey u get to be a test pilot for spin resistance!
Pilot: oh wow, i can't wait to fly the safe and steady Icon A5!
Icon: ummmmmmmm no u get to fly a c-150 at the ground in a spiral
Danny NBD
That's really cool visually. You can see how the inside of the wing is designed to stall first while the control surfaces on the outside maintain laminar flow.
Beautiful design. Beautiful engineering. I hope you sell a ton of them. Also hope you make a non-folding wing version so it can be cheaper so you can sell a ton more!
I have an Icon A5, but radio control. The RC version of most planes act similar to the full scale versions, as mine does. I can definitely stall it, but I also have more throw on the controls than the full size version. The aircraft is very controllable, and one of the "tricks" I like to do is to get it in a full on tip stall, and pull it out after falling about 50 feet. It makes sense what they are saying, I have control even in a stall, no doubt. The RC version is definitely not a trainer
Impressive and thank you for taking the enormous trouble of designing specifically to counter spins ! On another note, could I ask how the top of the tail has been tested for strength - having the forces all the way at the top end would put enormous strain and torsion force on the boom fuselage leading to the tail. thanks
now THAT'S FUTURE!!! CONGRATULATIONS ICON!! you guys are such an ICON!! haha
I just read on your website that new orders wouldn't be shipped until 2017... and I actually felt disappointed. As if I could even afford one! But something like this just inspires my imagination, makes me realize I want to do more "out there". You can't put a price tag on that, but someday I'll own an Icon. Preferably the A7 (two generations from now).
Hexagonal dimples or longitudinal scallops on top of the wing would create low pressure pockets as the airflow ramps over them. This would lower stall speed, allow greater angle of attack and increase lift.
So would longer, more flexible yet sturdy wings
I loved spinning C150 and C152s gives confidence. The wing low slip to land is also a confidence maneuver for the ones that come to high on final and still want to make the RWY a great breaking the speed off maneuver dirty flying, use the uncoordinated flying only while steep descending, level off coordinated and final check for airspeed, X wind consideration etc, wing low or grab into wind and rudder lineup, my favorite is the wing low landing in Xwind. On water beware not to tip the wing into water.
Saw this project when it first started few years ago. knew it will be a success in the future. just proud that you proved me right. Goodjob
Be proud of your tecnology is a good demostration for the FAA
Maybe get Tom Cruise to fly one. I'm sure he will be able to spin stall the plane. He likes doing the impossible.
Great work fellas! This A5 is beautiful! Too naff all I can afford is the RC version. And it's a good one also!!
Yes.. that was the point.. Power to idle, pull back stick, right rudder. To initiate a stall spin. Did you watch w/o sound?
The "Ercoup" [sic] (spelled Ercoupe) earned its Type Certification in 1940 by the now (highly) obsolete CAA. Its "characteristically incapable of spinning" behavior was achieved by robbing the pilot of any rudder pedals or independent yaw control. ICON's claim was that the A5 is"the first production airplane to be designed to meet the FAA's full-envelope Part 32 Spin Resistance Standard." This claim is 100% correct. Just calm down and enjoy an awesome feet in engineering and a sexy plane.
Its not an aircraft saving lives, its well trained pilots with the right attitude.
Spinning is an essential part of pilots education.
A Cessna 150/152 doesn't spin just after a stall! They need intentionally to spin it!
Actually, Cessna's are extremelly forgiving planes, too.
Not sure if I like the fact the rudder no longer responds in a full stall. It seems a bit strange that you can give full rudder in a stall and have the plane continue in level flight. Normally, the rudder is the one control that works in a deep stall.
1:32 Airwolf theme started playing in my brain
Looks like the reason for the stable stall is in part due to the tail high elevator is rendered ineffective being in the slipstream of the main wings and shadowed from the airflow.
The question is then, how much pitch authority do you have to get the nose down in order to resume safe flight from a stall condition.
The tail is right behind the prop. The main spin resistance design ques are found on the wingtips, but if the slipstream has something to do with it, adding power should give you full elevator authority.
I used to ride shotgun when my buddy would practice spins in a rented 150A. I always needed him to count each spin or I'd get nauseous. I had absolutely no problem doing a 0 G or any other type of maneuver that would make most queasy, but doing someone elses spins with no control on my end made me wanna launch, even after doing it for months. I never could figure out what my problem was there. As a side note, the aerobatic he'd practice in area was real close to his home, so we have pics of his dogs looking up at us as we're doing spins towards them. We always thought the dogs heard the odd engine noise and looked up thinkin' "that's gotta be daddy and his friend".
A safety feature I tought for passenger jets was 200 ejection seats when the plane is no longer flyable ( stupid idea anyway but with a good intention) but these airplane safety features makes my jaw drops. Why this technology hasn't been used in airliners yet. Parachutes have been used in space shuttles since long time ago. That could give to us...the passengers some peace of mind and stop being so worried about some plane failure that can makes us end up in pieces on the ground.
Surely canard aircraft with the smaller front wing at a higher angle of attack than the rear wing also prevent stall/spin circumstances?
Apart from that, way to go...
You got it. They claimed it had never been done but Burt Rattan did it.
Awesome work team, well done. Safe Skies 🛫
3:05 you see how the airflow is disturbed over the wing, except the part near the ailerons, nicely done!
I know this, my RC ICON A5 does spin in a turn with no power. The RC version likes to have power in a turn. Other than that, the RC version is so much fun to fly.
ICON is the Future on plane safety and Reliability.
REALLY ENJOYED THE TANDEM STALL TEST...Congrats
Crazy how the latest comment was one year ago... Still love this thing years later
A stall occurs when (and only when) the angle of attack exceeds the critical angle of attack. This is about 18 degrees in this type of aircraft. As the aircraft slows the angle of attack is increased to generate more lift and keep the aircraft flying. At that critical angle is exceeded, when the lift reduces dramatically and drag increases. The problem is NOT slow speed, it is that the critical angle has been exceeded, though in this case it IS the slow speed that has required the high AoA.
I think the overall Icon is fantastic - HOWEVER, I am very concerned about the substantial vibration coming from the stabilizer.
Not every stall results in a spin, that only happens when one wing stalls and the other does not. Notice in the video they put in full right rudder, so the left wing is going a little faster than the right, which stalls first.
Cessna said after the first Skycatcher crash that they went back to the wind tunnel, redesigned the vertical stabilizer and made the plane more spin resistant. Then they crashed another one the same way. Now they say they really have it fixed.
To everyone at Icon, my heart goes out to you and the loss of Jon and Cagri. My condolences to you, and the family of these two fine gentleman. Jon will go down in history as a tremendous historical asset to aviation. All the best to Icon. Amazing company, amazing family.
What happened to the pilot in the spin? They never showed him recover... what a cliff hanger episode..
Watch knees from 2:13 in video..control inputs are different. The 152 has full right rudder, the A5 has NO rudder input until after the stall. If the max rudder deflection is what is shown in the video, then the cross-wind landings of the A5 must be extremely limited. I'm all for the A5 going for FAR23 with no waivers. Let's just be fully truthful. Can it meet FAR23, stay under LSA weight, have swing wing and amphib gear? I fly an LSA amphib and know what a challenge that is. -Ken N52596
Interesting to see that the root has stalled but the tips still have the airflow to maintain control.Funny seeing in rudder and full back stick and still staying rock solid in the air.
Good ol' Burt Rutan designed non-spinnable, non-stallable aircraft more than 25 years ago...
Hell, some of the very earliest Aeroplanes were almost unstallable.
One example (but not the only one) would be the 1910 Bristol Boxkite.
Those used a forward cannard set at a higher angle of attack than the wing.
The cannard stalled (and dropped) before the wing would, dropping the nose and increasing airflow over both cannard and the wing.
I suspect Siggen (see below) may be on the right treack and Icon have figured some way of doing something simialr with the tail ... that said its has me baffled how you'd do that with a tail.
and the aerocoupe...the 30's?
Patrik Jonsson I have not seen it landing on land why
40 years ago! Burt is bad a$$
C-150 pilot steering to right in the slow flight (2:20). I5 pilot don't do this. The result you can see here ...
The icon did hit the right rudder. It looks like he hit it at full right rudder. You can see his right foot push down as far as he could.
yeah i watched that part a few times it it *looks* like there is right rudder applied on the a5.
A colleague pointed out that the Eurocoupe also claimed to be Spin-Resistant: See its wikipedia page:
'The Ercoupe was certified by the Civil Aeronautics Administration (CAA) as "characteristically incapable of spinning." '
Since you are familiar, why don't you explain. It seems reasonable to think that if the vehicle loses speed, it will "sink" as the air is no longer passing through the wings at speed and helping its structure move up or stay at a constant height. Please expand on the issue if you can. Thank you.
question. ok in a slow onset stall it won't spin what about a high speed dynamic stall? much more likely to spin off one of those.
Yes stall and spin and stall is a importent feat to master, for some who didnt hear they say that this plane is a Good plane to do training in is in fact stall and spin training in a safer way,
i know the training is hard and stressfull on new pilots and can be realy scary, but i is also a dangerus job for the instructor`s to teach a new pilot to recover from a stall and spinn.
to the hole team of A5, Amasing jobb!
I was clearly talking about the C152. The plane is spinned on purpose (banking right and right rudder), while the A5 only gets right rudder. By banking the C152, you are reducing lift, and therefore, with barelly any lift, any rudder input will therefore induce a spin immediately, whether on an A5 or a C152.
Second effect of yaw is roll. Watch the cockpit video
Fascinating, and very impressive.
I'd love to see more stall resistant designs...but for a different pilot certification category. I fly airplanes that are not "spin resistant" in prolonged, deep stalls, controlling heading, avoiding spins, and while rather "in control" of the event. These airplanes do what a well trained pilot asks of it - I like that about them! A lot of pilots (and CFIs) rely on crutches to get by with their lack of training and exposure to the full envelope and then one day, it bites them (or their students)
Yep with 300 hours in 172'a and many hours in other in other aircraft it is a deliberate act to spin them. The stall (and 152 stall/spin) in the video is only straight and level and power off where most GA accidents stalls (Over three years accident study) happen in low altitude turns, then take off, many over weight or out of G of G. Icon have also submitted a weight exemption of 250 pounds to the FAA sighting stall safety. The folding wings also contribute to extra weight so stall safety?
Stalls can be related to spins. If the rudder is ineffective in a stall, it's ineffective in a spin then.
beautiful aircraft... would love to learn to fly and buy
Is it still spin resistant with the engine stopped? In my head the draught from the prop over the tail would make a significant contribution to its post-stall controllability. Still cool though, like electronic stability control for planes.
I want 1, but a 4 seater & at least with 500-700 miles or at least a NYC 2 Florida travel time distance capability, but i guest even at top cruising speed (120mph) it would take about 7 & 1/2 hrs from NYC 2 Florida. still love it though.
look up raptor aircraft
Yeah, it has maybe two thirds of that range, and only two seats, and less of pretty much everything (except water landing and maybe stall resistance, based on their company video) than a Cessna c150. Also, it costs well over 10x as much.
I can't wait to buy one!
Want to limit stalling and reduce spin chance in any aircraft ? Fly with a thick pillow of appropriate thickness between your stomach and the yoke, or pillow between your knees if stick controlled. Other method, connect a steel wire of appropriate length between stick and dash board. I still would take an ICON. There are plenty of cool features to make it great besides just the safety reasons.
Very cool, looking forward to being able to buy one of these someday.
Hey thanks for the point out! I Honestly never got to the end of the video before! The lie at :37 tuned me out although I had watched through to the spin tests. So at the end of the video they weasel worded the lie they told at the begining of the video. Interesting!
Now that I have heard it did you notice the additional caveats? Was not the Beech Starship the first Part 23 spin resistant aircraft? (oops!) They had to throw another caveat on there. ;)
It's a shame it failed certification.
Please build something that starts and lands vertically. It's possible with hybrid engine burn+electric in ultra light aircraft, if the engine have more power for ~30 seconds (batteries).
I notice a pretty visible buffeting of the tail during the stall. Does that pose any structural concerns?
Thanks Aviation Engineers👍☺️💯🇵🇭
Noticed the same thing on the wing airflow. I kept waiting for the tips to stall.
Ejection seats in the hands of an untrained passenger deck would be far more dangerous than any potential saving capabilities they would offer. As for parachutes, larger aircraft are orders of magnitude heavier than this tiny little aircraft, the parachutes required to save this aircraft would be both extremely expensive and probably too large to actually fit on the aircraft. Even if they could fit, where would you mount the parachute that could withstand the forces as the chute opens?
I agree that they should probably shown the stall/spin characteristics with increasing bank angle.
Seems that the root is designed to stall early. The outer part of the wing, which has the best ability to torque the plane into the spin, is not stalled. This probably gives the plane its low sink rate while stalled.
ๅช0จ7765ฟผผฟผผผผหปกก
This looks impressive but the main question is how do they achieve it and why not do like Cirrus with a parachute system since the aircraft is so light. Performance would probably not be sacrificed. I would love to see a 4 seater Icon aircraft, I would probably buy a 4 seater.
+Charles-Etienne Roy They have a parachute -> check on their website iconaircraft.com/a5/safety/
Apparently the Skycatcher test pilots found a way, twice! I gather it was power on, cross controlled and intentional, but they were not able to recover.
amo el A5 espero con ancias el dia que yo tenga uno y pueda pilotarlo. De momento lo piloteo en mi flight simlulator con mis Meta Quest 2 :D
Isn't that the case already? Most folks learn on 172s which have stable stall characteristics. Not nearly as far as the a/c in the video, but still far more stable than craft with higher performance wings, twins, etc.
Don't people ALWAYS train on something easier? When you train your kid to ride a bike, do you put him or her on a racing motorcycle, or a bike with training wheels?
What a beautiful airplane! Awesome that it also capable of landing in water! Given engine is on the roof, where is the fuel stored? Is it electric?
Fuel is always stored in the wings. The fact that it has fuel should answer your next question.
in the video during the stall did you all see how bad the tale was shaking..Im sure if these catch on were going to read about the tails breaking off the plane like an old bonanza
However the definition of a spin is not one is still flying while the other is stalled. A spin can only be entered when both wings are stalled. One is just stalled more than the other.
This is very impressive... but I’d like to see dynamic critical alfa test results, to say, accelerated stall and spin entry behaviour...
As a long time instructor on GA Aircraft and having flown thousands of hours on Fly-by-Wire aircraft, I have observed and seen first hand conceptual misunderstandings on how all sorts of pilots, experience and low-time, react on the dreaded “base-to-final-overshoot” scenario. True: Not every pilot reacts the same, and many either increase bank, and/or worse, try to “cheat” believing that the rudder will solve their problem (very famous example of that was lCallsign Revlon”). Any info on those?
mate, the lead engineer Jon Karkow you can see is this video is already dead - crashed in an A5. Not the best track record for this little innovative plane..
Doing delayed recovery stalls I was doing well for 1 min, lagged behind, rolled left. 2 turns when I realized I had the rudder to the floor. Right rudder, spin stopped, 2 turns right. House, fence, tricycle turning counter-clockwise where the horizon should be. Instructor George Mejeur nudged wheel forward, I did the rest. Nose came up through horizon, said I forgot to neutralize rudder instead stepping on the right. I was embarrassed. He burst out laughing. Next week we did an hour of spins.
Stall does not mean that the airplane STOPS flying. It is an insufficient amount of lift to maintain level flight. Lift does not cease to exist.
I'm wondering when we cross the line from piloting to just driving airplanes? How is this a good trainer if it's flight characteristics are more forgiving then any other aircraft a person will ever fly?
Great stuff man, thanks for explaining where I was wrong.
We now know that an Icon A5 has crashed onto the shore of Lake Berryessa, killing Icon's Chief Aeronautical Engineer, Jon Karkow as well as Cagri Sever who had been working with the company for just several weeks. This occurred yesterday, May 9, 2017. It is not yet known if the accident was as a result of a spin or spin-testing.
I left a comment here three years ago, sufficiently impressed by this aircraft. When I saw this in the news today, I was saddened at the loss of two engineers. Seemed like such a cool innovative plane, but I'm curious to know what really happened up there.
Please someone tell me the song at 5:19 PLEASE!
what you see is that the outside of the wing never effectively stalls.
Very stable. That's great!!!
why did you remove Roy Halladay's video from your channel?
DXSW Roy halladay dies in a plane crash in one of these icon planes
So does Jon?
I'm not pilot (Yet!) but as I understand one of things the instructor makes you do when getting your pilots license is to educe a controlled stall then recovery. Kind of scary if the plane is capable of a flat spin no?
What's wrong with spinning? Nt buddy and I did 22 turns in his T craft over Moab. My instructor was watching in binocs on my first solo and I did 6 turns in the club Aronica. He grounded me for 2 weeks and required me to recite the rules for spins
Iguana.
Whats wrong with spinning? Low to the ground DEAD, small rudder DEAD poor pilot recovery method DEAD any other fuckups DEAD
I applaud ICON, however, just as Cirrus failed to positively impact the safety of flight, the big issue is pilot training and judgement. Rudder limiters, outboard leading edge cuffs, etc all come with increased risk in other aspects of the envelope and even if that weren't the case, exposing pilots to planes that reward them when they fly poorly is a bad way to prepare them to fly anything else, it trains them to safely fly only that one, particular, airplane.
They never should have removed stall recovery from the ppl.
??? Per the ACS you still have to learn Power On/Off stalls and do them to the full stall and be aware of the spin recovery... it is still very much relevant in Private ASEL/ASES
Who told you that LIE lol?
Can the aircraft taxi with the wings in the stowed position?
Wonderful!!! It just slowly flops down like a frisbee.
Wow. This video has elicited an impressive number of rather boneheaded comments. I think pilots should be trained to recognize and recover from spins -- I think at least introductory aerobatics should be a part of flight training, so that if somebody finds themselves in an unusual attitude, they don't just start screaming, but rather rely on their training to recover.
That said, I'm totally in favor of a design like the Icon, that won't kill somebody for making a mistake. Well done.
Where is it available and what is the price?
That's it, new life goal. Get to a position where I can fly/(own?) an A5.
I am 77 years of age...and I would give my life to fly this machine......! ICON A5
I have over 2000 hrs of flying time but this is a few years back already...?
You did a super JOB.......!!!
Brilliant! The owner must've got that idea from F-16 :)
I love the concept!
Not once do they explain HOW the A5 achieves spin resistance, which leads me to suspect that the A5 sacrifices performance in some other area.
I suspect that the high placement of the tail elevator is how they achieve it. In a stall, the center of pressure will be above the center of gravity, and the aircraft will subsequently stay upright. The C-150's tail elevator looks to be placed at or slightly above/below the center of gravity, rendering the aircraft inherently unstable in a stall. The A5 acts like a human under a parachute, or like a badminton shuttlecock, they right themselves in a vertical fall, since their centers of pressure is above their centers of gravity
Thats more then ok, if performance suffers for saftey thats fine
Well, yes & no DJ787.
How *much* performance is lost in the trade for safety - and where its lost - is a legitimate consideration too.
For instance, if the trade was to up fuel consumption that would have a safety negative implication too (you don't want to run out of fuel).
Now, you could with some fair grounds argue 'Pilots should have more sense than to run out of fuel'.
But then, they should have more sense than to stall too.
Reality is the dumber ones do both.
That said, what this company is doing looks promising .......... Just hope that if there are drawbacks the 'safety at any price' brigade doesn't get to shove it down everyone's throat.
Siggen, Actually, The T-tail configuration is more susceptible to uncontrollable stall characteristics. Just look at the Beechcraft Skipper and Piper Tomahawk for example. The way the Icon's wing is shaped, With a shorter root chord and longer tip chord, as well as a higher root incidence angle than tip angle, ensures that the root of the wing stalls well before the tip of the wing. It essentially makes it almost impossible (very difficult) to stall the entire wing at once. The loss of lift during the partial stall causes the nose to automatically drop before the tip airfoil reaches it's critical angle of attack. This technique is called aerodynamic twist and is commonplace on most aircraft. It is just utilized much more extensively in the A5.
Ashore4 Interesting to hear, I was just speculating wildly, nice to hear someone with more knowledge explaining it
I just love this video.
Helio Courier also. 1954, I believe.
What about power-on stall spin?
Does anyone know if they made this plane spin resistiant through aerodynamics, or through fly-by-wire??
It is a nice aircraft, the accidents occur when people think they can do more or be maverick. It is a tourism aircraft that I would buy soon If I had the possibility.
I absolutely agree with you, but the plane is still a decisive point... I mean, if your plane got the reputation to be unstable on stall/spîns, even with the best training in the world, it does'nt change that much...
They state up front in the video that they deliberately stalled both aircraft. They're not trying to fool anyone. While some of their claims may be exaggerated, they have built a very impressive little aircraft.
But it seems none the so called experts are engineers.
The spin resistance appears to be due to the wing design vs limited elevator travel.
Look at the streamers on the wings during a stall the main parts stalls but the ailerons are still in laminar airflow allowing control to be retained.
This is likely due to some serious CFD work.
CFD modeling did not even exist when the ercoupe was designed so this is a far more advanced concept.
"if" this airplane ever does get into a spin....will it be recoverable?