Plane: stalls Ropes: *now it's time to get funky*

@davecrupel2817

4 жыл бұрын

XD

Respect to the pilots who stall planes all day for science. o_O

@coriscotupi

9 жыл бұрын

As a former flight instructor, I used to stall, spin and let students land the airplane all day long, day in, day out. Loved every minute of it, too.

@naperking

9 жыл бұрын

corisco tupi Thank you for being an awesome instructor! :) The best way to learn is to fly, 'nuff said.

@coriscotupi

9 жыл бұрын

KingPNW Thanks! Unfortunately, as intentional-spin-approved aircraft were eventually phased out of our flying school (we used to fly mainly ex-Air Force T-23s for primary training), I didn't get to do any more spininng. Primary training reverted mostly to PA-28s, so training became much more sedate so to speak.

@jjaus

8 жыл бұрын

+strangersound I started flying in the 70s and early 80s. We had to stall and spin as part of our training.

@_ShaDynasty

7 жыл бұрын

its fine. as long as you have plenty of altitude .

Excellent video. I am an instructor at an A&P school and I show this video to my students when we are discussing stalls and aerodynamics. They absolutely love it. Thank you for uploading it.

Never mind the plane ! What a gorgeous little red tractor .

This thing will still be flying as he taxis it into the hangar

One of the more valuable videos on KZread. Thank you for your time in recording and uploading.

thats amazing how just changing the airflow a slight bit improves performance by that much! very impressive guys.

Very well illustrated!! Im going to install VG's on all my model airplanes now :)

@Omnidestrophic

4 жыл бұрын

They are super cool. and the science behind them is even more amazing. The fact that the vortexes created actually help the air stick to the control surface is awesome.

Such an instructive video. Thanks for your labor. Well done!

Thank you! A lot of time was spent doing this experiment and it was extremely helpful in my decision to install VGs on my airplane.

We added a VG kit to our stock standard 160hp Cessna 172N model a few years back and it changed the whole aeroplane. The first Cessna helicopter! The very low speed handling and very slow speed stall characteristics were there to see in the very first flight. Quite amazing really. I wouldn't want to go back to it's previous life not having VG's knowing now what VG's have done to it. In some configurations it seems almost impossible to stall..the ASI reads as low it can go on the dial. You don't even notice any change in IAS. It's only a 100 knot 172 afterall. So that's Yes Yes Yes Yes for VG's..

You guys really deserve big like (y). Thanks a lot for great video.

Studying this in ATPL's and helped massively. Brilliant work gents!

This is an excellent demonstration of the effectiveness of vortex generators. Well done.

Great visuals!!

Very well sir I do really appreciate your work and amazing outcomes

Great demo guys. Im glad you fitted the VG's to the outboard wing first for the test... not the inboard...!

@diao77723

4 жыл бұрын

Would that be to allow the inboard wing section stall first and allow you to maintain full control ability of the roll axis?

@henningoden153

4 жыл бұрын

@@diao77723 Exactly. With the ailerons still in laminar (unstalled) flow, you have roll control. You lose that if your wing tip stalls before the root and the inboard section, being wider on many planes, provides more lift than the tip.

EXCELLENT video. The kind of testing that really is instructive. THANK YOU!

This video is awesome. Great work. Surprised all airplanes don't have these installed.

That tractor is really what's pulling those jets when "Delta Super Tug" calls Kennedy Steve.

Thank you for uploading this.

Very interesting. I love this stuff. Thanks for posting :-)

This is the best video I've seen to date on this topic

Spectacular video! There's so much going on here! My son and I will be discussing the visible aerodynamics for weeks! Major thanks for posting this!

It's amazing how you can change the manufacturer designed stall speed on an aircraft so drastically just by adding those (what boil down to) simple little stick on devices. That's cool!

Thank you very educational

this is really great video for understand, thanks a lot for your amazing effort.

Fascinating! so clear to see.

Excellent experiment ❤❤❤

Nicely done!

I now think I know what I’m going to create and stick on my motorcycle’s fairings today. 😁

Fantastic video! Thank you for taking the time and also sharing the video! VG clearly make a significant difference to stall speeds at different configs. The transcript is pretty hilarious though - I don't think the researcher actually says "and takes a sexy" at 12:11 🤣

I love that tractor!

great video!

Great video! Thank you!

Very interesting experiment! Seems like the ailerons work well past stall angle of attack of the wing. Reminds me of the zigzag tapes we put on som gliders. Low speed handling and induced drag usually improves, at high speed drag can increase but not by much. But it seems to depend on the airfoil shape. If I remember correctly the chordwise placement of turbulator tapes is also rather is critical.

Great video

GREAT VIDEO!

great video, it helped

good experiment :D

Fantastic, Thanks!

Amazing Video thanks for sharing

Very good. What I'm looping for is the mesuring over and under wing surface. I hardly bealive in pattern usually shown. Regards

Quite impressive

I see, that they delay the stall but then when the stall does happen it is quicker and more violent. They would also effect fuel economy at the cruise. There's a reason that small plane manufacturers don't use them and I suspect this is why.Many thanks to the poster for doing this video, well done.

I obtained my PPL in 1999, so learning stall spin recoveries in the U.S. was not required, but my CFII insisted I learn, so I reluctantly did. He did not even charge me for the time. Glad I did learn though. I must admit that I never practice stall spin recovery.

@rparker449

6 жыл бұрын

Hope you remember what to do the next time you stall.

Loved this video. Loved seeing the tell trails of the when laminar flow detaches. What sort of black magic are VGs?!

These arent pilots. These are scientists with a huge pair of balls.

Very interesting. This should be sent to the developers of Microsoft’s new Flight Simulator. Apparently now more than 1000 data points on the aircraft to measures forces, where in the past there was only one!

thank you very much!!! it's great clip. ขอบคุณครับ...

Please, measure the fuel efficiency with and without GVs

@MatthewHeiskell

4 жыл бұрын

Good idea!

@nuclearwinter21

2 жыл бұрын

Gonna need to fill the tank twice. 👌🏻

Cooli sach! :D Echt spannend das so Visuell chönne z gseh.

Altamente didático!!!

@mog882

6 жыл бұрын

Gessé Costa English damn you!! English...this is aviation not some silly party with weird europeans.

@leandrolefa

4 жыл бұрын

@@mog882 this is the internet. Use a free online translation service.

It helped me study

Looking at installing VG on my upcoming plane and want to ensure that I fully understand the need/safety implications/lower stall speeds/lower takeoff and Landing speeds that VG provides.

I imagine if the overall vortex strength generated is opposite to that of the wing tip vortices of each wing, the tip vortex strength would be reduced, thereby reducing vortex drag. Essentially like a lot of tiny winglets. Alternatively, the added boundary layer energy could improve the aerodynamic efficiency of the wing, especially if it cruises near flow separation, causing better performance.

This could have been highly classified stuff, thank you so much for sharing it with me/ us. Incredible information.

TK very much goodnews

@caadhan

10 жыл бұрын

very good pic TK very much ur kindness

I remembered I was flew Qantas Boeing 707 with 50% metal vortex generators in 1977.

Super

Congratulations for this beautiful stall invention that u guys developed, hair hope u guys can sell this to our airlines that will take notice on this technology, as we really ness this for now instead of the future of flight! Once again...BRAVO!!

With cruise power negligible, with max power my be a few kts. On my Zenair 601HDS with all the VGs installed the cruise speed is 8kts higher with the same power setting (fuel flow).

WOW!

How much did your fuel burn increase after install? And any top speed decrease associated with the extra drag?

sorry, but at minute 04:30 more or less, I saw a black pint in the up right corner of the wing, was that something inside the plane or some kind of stain in the glas of the window? or that was something flying outside of the plane?

Great video. Does the wing have any washout? I'd expect to see this stall pattern (even without VG's) if it does.

With those vortex's you can make the tractor fly. Cheibe guet!

So nes superguets Änglisch! Aber merci für ds coolä Experimänt!

@celus1444

4 жыл бұрын

Hahaa =)

i hope one day they will make movable vgs as a standards on all planes like they have flaps

NICE, how much drag dp they produce on speed flight?

since the tailplane flies with with downforce, could you install VG's to the underside of elevator to maintain laminar flow at low speeds/stall speeds?

Im looking at doing this to my aircraft to, is it a hard process to determine where to fit the vortex generators on the wing? I will be installing them on a rag and tube wing.

Was angle of attack consistent throughout all tests?

How do the vortex generators affect the flight characteristics, apart from just dramatically reducing the stall speed?

@sadmansakib3644

3 жыл бұрын

Reduces maximum coefficient of lift, increases critical angle of attack, increases induced drag

Amazing - so why aren't they fitted by aircraft manufacturers?

Amazing! Is this perhaps why golf balls have these tiny "holes" - they create vortexes which help the air better follow the curvature of the ball and eventually lower the overall drag?

@marekskokan

6 жыл бұрын

Similarly to VGs, as you know, the holes enable slower air close to the surface of an object (e.g. golf ball) to mix with the air that is a bit further away from the ball (which is flowing quicker). The mixing causes that the air close to the surface flows quicker (it is energized) comparing to the airflow speed without holes/VGs (talking about the sides of the ball, not the "nose" in front). And that is the whole point of pushing/manipulating so called flow separation. On the golf ball the flow separation is thus pushed further back when comparing to the ball without such holes (as the quicker airflow resist the airflow from behind the ball - where the higher pressure exists - to go backwards - also see the strings flying opposite to the direction of the aircraft speed at stall speed). Even though mixing the air costs some extra energy/drag, if you have shape of ball (you can do nothing with the overall shape in this case) the most drag comes from the area behind the ball where turbulent airflow exists. The volume of the air in this area with turbulent flow behind the ball basically goes with the ball and cause the friction/drag. In case of golf ball, as the flow separation is pushed backward, the area with turbulent airflow behind is smaller comparing to the ball without the holes. Simply they (golf balls) can fly further thanks to the holes and the overall drag is indeed reduced thanks to the holes as well.

Clearly the VGs lower stall speeds, but would they introduce another icing surface on the wing?

@dylconnaway9976

4 жыл бұрын

Loss of control accidents are more prevalent than icing accidents. My thoughts are the threat of icing doesn’t outweigh the daily benefit in terms of safety the VG’s account for.

@rkan2

4 жыл бұрын

I doubt this plane should even fly in icing conditions... Most non-turbine airplanes are not capablebin icing conditions anyway.

I'd like to see this on motorcycle windscreens to see if it can reduce helmet buffering while still using a smaller screen.

great video and visual info. i was very curious why do they put the vortex generators on where some are straight some are at a angle. is there a correct angle to use for this? and why put them under the winglet i saw some there also?

@rparker449

6 жыл бұрын

A generator at an angle will cause a larger vortex than a generator pointing straight into the relative wind. The size of the vortex determines the thickness of the laminar boundaries you can influence. In this way, you can steer each lateral boundary of each segment of laminar flow between two generator positions.

Why the VG's are placed on the leading edge, it wouldn't be better if placed where the airflow separates on the middle of the wing ?

Looks like the pilot added a little aileron a coupe of time as the stall progressed with VGs off

Why you delete the flaps? They act as air breaks during landing.

does the difference of speed to hight degrees create the vortex

Классно

Back when I was a CFI, one day I covered the wing of our trainer aircraft with such yarn strips and flew it all day like that, showing student pilots the visual effect of stalling. They were all delighted to see first-hand something they had only studied in textbooks. ...I take it those VGs are not certified for general aviation aircraft? How does one go about installing them? Will the airplane not be illegal with such a radical aerodynamic modification, however beneficial it might be? Would the airplane need to be re-registered as "experimental"?

@jimstanley_49

3 жыл бұрын

0:17 This aircraft is experimental. They just had to update the magical paperwork that allows the plane to fly, I assume with data from the VG manufacturer and the new performance data from test flights. I think you can get them for non-experimental, but the manufacturer has to have done all the magical paperwork.

@coriscotupi

3 жыл бұрын

@@jimstanley_49 Somehow I managed to miss the big "experimental" painted there. ...And "magical paperwork" describes it nicely. Thanks for chiming in. Cheers.

The video is extremely interesting, however, as a pilot, may I just disagree with the saying of "Stall Speed"? Stall is technically given by a wing angle of attack. Every wing has one and beyond a certain angle, air simply is not allowed to accelerate on the upper part of the wing, hence no low pressure created. What you call stall speed, i'd call "minimum speed". You can travel at minimum speed, having to work with feet and bar to keep it flat and stable. At actual stall, unless the airplane is perfectly flat and balanced, the nose would naturally dive down, otherwise it wold start a spiral. Correct me if am wrong

I would advise caution in doing this on half a wing as your changing the loading characteristics along the length of the airfoil.

Do anyone come up with the idea of retractable VGs? They could be retracted during the cruise and stick out during take off and landings.

Sure it works for low speed. Do you lose any cruise speed ?

@hbykv

9 жыл бұрын

No speed loss in cruise speed. The nose is 2°-3° lower in cruise with VGs, better foreward sight and may be less drag. Viktor

@rparker449

6 жыл бұрын

Usually hanging anything out in the airflow will cause drag. But the vortex generators are first, very low profile and small relative to the relative wind. The generators, as tiny as they are, create a large pressure density fence to contain each band of flow from nose to trailing edge. Each fence acts to to keep turbulence in rootward segments from leaching tipward across the wing length. A naked wing offers little resistance to lateral flow from root to tip. Stall turbulence thus creeps along the wing freely. As for drag, each vortex serves to bind and reinforce the laminar nature of flow from nose to trailing edge. This orderly flow will cause lower drag as the sheer from skin to free air is thinner with generators. Without generators, the laminar sheer profile is thicker and more turbulent. Probably explains the 2°-3° lower angle of attack. The naked wing with sloppy laminar flow was being robbed of lift so it had to cruise at a higher AOA. The VG equipped wing encourages lower drag requiring less bite into the relative wind at the same cruise speed.

Ok, using the VGs you can indeed reduce the stall speed but you going to mess up the cruising and top speed characteristics of the airplane. If there was a mechanism that could retract / extend the VGs on demand, then the entire project would be viable, as it is it only serves as a verification of what flight dynamics engineers have discovered many decades ago.

@hockeyme3113

5 жыл бұрын

Any device that retracts vg's would just be extra unneccesary weight. It's possible, but not practical.

@jonnekjonneksson

5 жыл бұрын

@@hockeyme3113 not necessarily ANY device, as it depends on the particular airframe application. For example, a lightweight VGs retracting device could be beneficial on a 737, if of course we take as an established fact that gaining 15-20 Knots of lower stall speed is really something that we desperately need.

@hockeyme3113

5 жыл бұрын

@@jonnekjonneksson in my opinion it isn't worth it. This is coming from an A&P perspective, not a pilot's. The plane can already be landed effectively at speeds without vg's, so in my opinion it's just useless weight.

Unreal. 15 knot change.

Is it just me or does that wing have a high angle of incidence?

My question is what were the level cruise speeds differentials with VG and without VG. Was it a large difference between the two. My research has found that it about a 1 to 2 kts difference in level cruise. As with Aviation, there's always a give and take scenario.

@jonasbaine3538

Жыл бұрын

I rather lose a few knots and slight fuel use increase to improve controllability in critical situations.

why did they do the 60% test?

What was the actual landing speed?

I wonder what the difference would be if; Vortex generators were straight. If you put the generators just behind the max chord thickness at the separation point.

👍

Nice, just imagine how many more hours per gallon at cruising speed you’ll get with reduced (wing tip induced vortex working against you) a better drag coefficient and more effective airfoil function (more lift at lower speed) you wont have to work the engine as hard or hang on the prop to get out of ground effect. Just imagine one thing, this is old technology, old! How many hazards or tragedies could have been averted if they were in place 50 years ago? Improved glide rate, plane control, reduced minimum landing speed, less stress on the airframe, I’ve been bringing these things up for years and no one listened.

Good video!

I cannot make sense of the airflow , fiber or yarn moving in all direction.