Pelicans use ground effect and a phenomenon called dynamic soaring. When you see them pull up and turn into the wind before heading back down between the waves, they are gaining a very slight amount of total airspeed due to the different wind speeds in between the waves and at the wave crest where the air is being compressed. You should check it out if that kind of thing interests you. Rc glider flyers have managed to break the 500mph barrier using similar techniques but on mountain tops instead of ocean waves.
@Michael Nickname Yep. The real max airspeed number is actually higher than that but the point at which they take the reading is the slowest part of the circuit. The formula they came up with for calculating the max speed from the reading on the radar gun should put it between 560 and 600mph. The guys doing this are at the top of their game in regards to flight skills, building skills and aerospace engineering ability. ruclips.net/video/nv7-YM4wno8/видео.html
@@shmaknapublar thats right, there are some good clips on Ytube of the RC gliders doing this. I fly RC slope, used to fly RC helis and powered planes...which were great fun...but RC gliding is in a different league:)
The air is not compressed. Compressibility of air is negligible under mach 0.3. Lift in increased and induced drag is decreased because of the proximity of the ground.
I was 40 years old, learning with a experienced instructor in an aluminium glider made in Chekoslovaquia ( Blanik) . I was aproching final and he talked to me and made me rest some time away from the landing field. Before the landing field there was a wired fence for cows ( in Bahia Blanca, Argentina ) . He then asked me if I think that we will managed to arrive with enough altitude to surpass the fence... I told him that I thought we would NOT ... He told me to try my best, and I did it. We flyed up to where the fence was and we were already beneath (the fence is 1,20 meters high). So we were flying less than that ( may be 0,70 meter.) I kept cool, knowing he was teaching something I didn't know. Just before the wire fence he said " just skip the fence and get down again" and we did it !!! ( I was absolutly astonished, gratefull and very happy to learn in practice this theory.) Now I am 74 ...
RetroGamerVX it’s because the extra high pressure air caused by the air bouncing off the ground and striking lower surface of the wing, adds to the pressure differential between the upper and lower surface. Ie greater static pressure (on a surface) below. It’s not the cushion itself because weight is still acting downwards so it’s always explained by the differential.
Ground effect has nothing to do with a cushion of air. There is less drag due to WTV's being cancelled out by the ground below reducing drag. This is why airlines started adding Wing tip generators. They effectively reduce drag on the linear axis of the wing root allowing a more efficient wing
K. Bierman Oh dear, quick lesson on aerodynamics. The glider flies by accelerating an Ovid cylinder of air roughly equal to 1.4 times the wingspan. This mass of air has the downwards momentum of the time the glider was in it, plus the wasted energy of the tip vortices. Now, ground effect. Close to the ground the air cannot gain a downwards velocity so the energy that accelerated the air down is no longer lost, plus the diameter of the tip vortices is reduced from the 1.4 span effective area. So, saying the air under the wing (and more so in front of the wing) is somewhat accurate as it has the force of the gliders weight acting on one side and the ground pushing back on the other side instead of free moment.
I used to fly a Schweizer SGS 2-32 many years ago. Your aircraft has a glide ratio we could only dream about! Great video, thanks for posting it, that really takes me back.
I saw competition pilots use this effect to approach the field, running low at high speed from 2 or even 3 miles out the runway. Very beautiful, but sometimes not so funny...
Jose Marmontel these finishes were discontinued for being too dangerous. There were fatalities, including among the spectators, who often gathered in front of the finish line to observe and take photos of the low flying gliders.
-Northern California, waiting for my 'ride', as landing glider was in G.E. too long. It raised tail, slid on skid, hit the restraint barrier chain link fence, damaging wing, far beyond end of runway. "No ride for you"... ;
Fast calculations: 24 sec over airstrip (before pulling up for landing) with speed decreasing from 75mph to 70mph gives around 780 meters flown. 75mph to 70mph is a loss of energy that is equal to 7.2m loss of altitude. THAT GIVES A GLIDE RATIO OF 106! Note that changing speed loss for eg. from 74 to 70 gives L/D 140 ;) but glide ratio is for sure bigger than 100 which is still awesome
Thank you. I wasn't looking for this kind of video but it was a random pop up in my feed and was very enjoyable to watch. I am now looking for a glider flight near me.
Some rainy day when you want to go for an hour-long flight while sitting in your living room, grab a drink and a snack, enter THIS pilot's name in your search bar, and pick one of his flights to stream to your TV. Some may find it boring, but I find it exhilarating. He slides through the sky riding lift from ridge to ridge, and covers hundreds of miles. There is no crash, no burst of flames, and no accompanying music, just the raw experience of glider flight in the amazing Rocky Mountains. The beeping of his barometer is an emotional thing, triggeringbexcitement when chirping a high tone and concern when making a low tone. It sounds out if the glider is rising or sinking. On a good TV , you can see the gauge at the upper left of his dashboard, which also shows graphically his rate of climb or descent.
@@logmeindangit I've been there for a few days. Random video, now contemplating a demo ride and getting licensed. Club 30 min away. Had no idea flights could go so long, so high. Tonight searching for solutions for a full bladder...lol
I flew out of Estrella SSE of Phoenix and LOVED practicing high speed low approaches. Turning base and final from 10 - 15’ off the deck at high speed. I was flying a Grob 103 (57.5’ wingspan) so you would have to pop up to make the turns and then push it back to the deck. Serious fun.
It was my understanding, that ground effect is created when the wings are close to the ground, they create a high-pressure Zone using the ground to push back a force to the wings, making them more efficient compared to open air.
This is great! Thank you. One thing though: ground effects are not a reduction in drag. The air flowing between the wing and the ground flows according to the Venturi effect, increasing air pressure under the wing. That's what lets you float.
Awesome save with the landing gear!! 2:37 I've been binge-watching your videos and the way you handled and control your girl is damn impressive! 99% of people who drive are nowhere near 'as one' with their cars as you are with her. It is a pleasure to watch.
i have some flight time in a mooney. exceptional airplane but due to the ultra efficient wing, they just dont want to land. there is some technique involved to land in a reasonably short distance. they get into ground effect and want to keep flying.
@@adamey5935 Get the aircraft into reversed command flight when on the final leg; that is, nose high, high power setting slow flight. Reduce power and slowly pull up to lower speed until you both lose speed and altitude. At this point you're in reversed command. Add power to maintain your desired sink rate and watchout your speed, you don't want to stall.. Regulate speed with elevator input and sink rate with engine rpm (power).
I think ground effect is a cushion of high pressure air formed between the wing and the ground. The wing itself has the same drag, but induced drag is lowered.
I scrolled down to see if someone explained this properly and this is it, to see the effect vividly google Ekranoplan ruclips.net/video/V8Nu94khHoo/видео.html
On a side note - The legend goes that the Buccaneer can actually ride on its own shock wave at low level, and naturally stays at the height where the pressure from the wave counteracts any tendency to drop lower - this ground effect was about 18 ft and it became the operational height for interdiction at over 600 knots. A USN admiral who had encountered the Buccaneer during joint Nato naval exercises previously and remembered the welcome they got as the USN fleet came into British waters. A flight of 4 Buccaneers went out as a welcoming party and requested permission to do a fly by "over" the US carrier. Permission granted, nothing airborne over the carrier, all clear, now fly bys were usually a tight formation pass over the ship or fleet, not this time, the four ship Buccs split to send one down each side of the carrier at deck height, the other two straight along the flight deck at very low level and high speed and if accounts are correct, one did the pass inverted.
Years ago, Boeing had a huge cargo plane on paper, perhaps even built a prototype, called the Pelican that flew on this principle. The intent would have been to move many tons of freight over the ocean, flying twenty feet or so over the water in a huge plane that would require very little fuel, with a range of many thousands of miles.
That was an old soviet design to carry troops, tanks and perhaps even short-mid range nuclear weapons to American shores, you can still see one of the devices sitting in a yard near Moscow, rotting away...
I remember an article in Popular Mechanics about the Boeing project. They usually design them to fly at higher altitude to cross land and other obstacles.
The wash that goes over the trailing edge of the wing is deflected by the presence of the ground effectively reducing the angle of attack which naturally reduces induced drag. That is what ground effect does. I had to explain this in depth for my CFI check ride.
Great demonstration! A friend of mind found out the hard way, he came in to land too fast (in a Schweizer 2-22) and he flew over the whole landing strip until he pulled up at the end of the strip, stalled and fell like a flyswatter.
Can you calculate the reduction in induced drag in ground effect? The ASW 27B will do a 48:1 glide at altitude, but in ground effect with, maybe a 10% reduction in drag...53:1 ? For those who might not appreciate the performance of these sailplanes, that runway is 6300' long! Great demo Bruno, thanks
Easy to calculate if you know the height above the ground relative to the wingspan. At a height of half a span above the ground the induced drag is reduced by about 8%. At a quarter of the wingspan it is reduced by about 20%.
Many years ago for my birthday a friend gave me a $50 gift certificate for a tandem flight, at llano ca. It was great, it sounded like we were a jet instead of a prop job, the instructor said do you want to do a loop, and without hesitation said sure he said watch the G- meter in front of me, we pulled 4.9 G's .. I could almost imagine now how military fighter pilots must feel, then the landing was scary because he came in just like this guy scrapping buts as I felt! I never never been that close to the ground on a landing ,and I hoped this guy knew what he was doing! Loved the experience! So I purchased a gift certificate for my dad and he loved the shit out of it! This is a bucket list thing , do it if you can! I've also skydived 30 times in California City!
Bruno, would you shoot a short video looking along the wing trailing edge showing what each of the flap positions looks like? I'm kind of wondering if 1 and 2 are reflex and just how deep landing flaps are.
Should have started at maximum 60 knots instead of 80! My usual ground effect demo is to do a standard approach to the start of the runway at 55 knots (in DG1000) and then at the last moment close the brakes and cruise on down to the far end of the runway.
I hear ya - I actually had never tried this before so I didn't know how far down the runway I would get before the speed bled off. I was shocked I only lost 5 mph over that mile. I was totally expecting to bleed off at least another 15 during that time. Modern sailplanes still amaze me even though I have a lot of time in them. Fun stuff. I'll try the 60 knots at the end of the runway next time. Take care, Bruno
Very cool. I had no idea of this effect, and how it plays out in reality. And while I'm not anyone trained in any sort of flying business, I find it very enjoyable to watch a video of someone doing something that they're obviously very good at.
Thank you Bruno for this informative video. I was surprised at the distance you glided at that low altitude. I thought for sure you would touch down short of the runway threshold .
Just shows you how amazing modern sailplanes (gliders) really are! I had so much confidence in what the ship will do that I was willing to put my butt on the line to show you. Go take a glider ride and see for yourself. You will be amazed! :) Thanks for watching.
Great demo. Cool shadow at 1:47. I was about to correct you: You said ground effect decreases drag. I always thought it increased lift. Some online research tells me that it does both. It decreases wingtip vortex and lowers the angle of attack of the wings slightly. I guess I'm a bit of an aerodynamics nerd.
When an aircraft is flying at load factor 1 (unaccelerated flight, as in not manuevering) the lift produced is always equal to the weight of the aircraft times the cosine of the flight path angle. Flying level in ground effect you have exactly the same quantity of lift as you would at 1000 feet, with considerably less induced drag.
The actual physics concerning ground effect are quite simple: Above the wing is a low pressure area, below the wing is a relative high pressure area. What happens in flight is that the air will want to move from the bottom to the top over the wings edges. This is why you see vortices around the wing tips. It is also why planes have winglets at the wingtips. To prevent this air from rolling from underneath over the wingtip to the top. Whenever you get close to the ground, this rolling motion is interupted by the ground, therefor acting as a sort of winglet. So no, you're not decreasing drag, you are increasing lift, which makes you put more downrudder in to maintain altitude, therefor maintaining a lot of your speed. I'm oversimplifying this effect, but in a nutshell that's how it works.
Flyingdutchy33 the wing in ground effect doesn't produce more lift. If it did, the glider would accelerate away from the ground. This is a fundamental topic: if we are flying level, we are always producing exactly the same amount of lift regardless of speed, altitude, etc.
Ground effect is created by the turbulent air from the tip of the wins call vortice, this air hits the ground and bounces back to the bottom of the wing creating a cushion
Great demo. I understand well how ground effect works. Same for Helicopters. But I am curious about your saying drag is reduced during ground effect. Perhaps I should google as you suggest. :) Edit. Just googled it. So much for my comment "I understand well.." LOL. So much more to it. I soooo love physics. :)
Drag will be reduced. You need less AoA to maintain lift to staying in air. This reduces the drag. Of this reason the ekranoplanes were inventet . Look in Google vor russian Caspic Monster .
The higher the ratio between the induced drag and the parasite drag, the more helps the ground effekt. When a glider ist flying fast, he has a low ratio between the induced drag and the parasite drag, so ground effekt can't helb very much. I think the main reason for your 'ground effekt' is the updraft of warm air above the hot runway and only a little bit of the real ground-effect. Can you repeat the same experiment at a time, when the runway has exact the same temperature as the environment? Perhaps at 7 o clock in the morning or so?
Good that you had the speed to pop up and deploy the wheel ... I guess you were really close the ground! Hey, maybe you can answer a question I've not found the answer to. When do you raise the wheel on take-off? Do you wait until you release from tow, or do you do it earlier? So far the two gliders I've flow have fixed wheels (still call "wheels" on my landing checklist, of course).
Wrong. If this happens to a racecar they take off towards the sky, do some fancy flips and crash in a very bad way. In a race car, u want the complete oposite of this effect - Not a cushion of air on which you can ride, but a low pressure area, close to a vacuum, to suck you on the ground generating douwnforce and grip.
@@spookyshark632 Correct, the ground effects in the Lotus utilized the low pressure under the car and accelerated the air flow in order to increase suction towards the ground.
Well, it's also going to help more by being over the paved runway versus the ground. There is a much, much higher temperature coming up off the black tarmac then it would be from the ground.
methinks any "chaffcutter" engine powered aircraft pilot should take note. Firstly - there is no "go around" option. While yes, the "glide angle" differs ... Learn to bring any aircraft to a safe stop on whatever,any flat ground within the glide angle.
Tasin Al-Hassan there is no cushion of air. It’s the wingtip vortices being disturbed and not allowed to progress and develop that is happening here. It’s only a decrease in drag.
Tasin Al-Hassan google or RUclips Bold Method ground effect. Bold method explains everything very well they have diagrams and short videos to show the decrease in drag due to disturbance of the WTV’s.
I have a video on my channel demonstrating the Schweitzer 1-26 in ground effect. Despite being a low performing stubby little thing, it floats like a hovercraft in ground effect.
I started training in a Katana, which is just a motor glider with the wings clipped. It would float FOREVER on a warm day. I found it annoying. Love it when I transitioned to a Skyhawk, and it would actually land when I told it to.
Yeah...higher order of thinking when you know kicking and throwing a bag of air is wasteful to watch. Don’t get me wrong...I still like a good competitive football game but let’s not leave our brain to waste on fanatical TV games
Brian Xavier because football is easy to join whereas gliding requires more skill. Not saying that football requires no skill just the entry level of skill required for is gliding is much greater that foorball
Brian Xavier To answer your question...... people who love to live life to the fullest do this...... glider flying. I did it years ago. I'm getting back into the saddle at a nice young/old age. Nothing like it!!
Hi Bruno, i am wondering which flap settings u do on 2:36, i guess 1 to 3 to 5 (Landing), and i would like to compare this to a 20A. Because, on the 20A Flappossition 5 (1st Landing Position) you should push the nose noticeably down. You do this anyway, but i guess very slightly, also not as intense as it should be in 20A. What do you think?
Hi Roland. I love the 20! you are a lucky person to own one. Congrats. I pop up out of ground effect to adjust the flaps because I would never want to adjust them down so low. I initially move them down to thermal flap and then a few second later down into landing flap. The 27 only has one landing flap while the 20 has two. Consider me putting it into the less aggressive 20 landing flap setting at the end. Hope this helps.
illyonka que la portance augmente et que la traînée diminue. La portance c’est la force qui pousse l’aile vers le haut La traînée c’est ce qui freine ton avions ou ta voiture
Loved doing this in the IS28-b2 and hornet206 very long high speed run up the field to the hangar, 30 foot incline over 1 mile, was always the highlight of a long days flying.
You can skip off of the ground like a flat rock on water, or in space travel, like aerodynamic landing modules that enter the atmosphere of a planet and need time to shed airspeed.
This can be pretty annoying when trying to spot-land an RC model. It's like the model is fighting you. Sometimes the plane can skim so far it's airspeed decays to its stall speed, and you just Bobble for a moment, then mush through the cushion with a thud!
Don't have as much drag as the usually do? Isnt it much more the effect that the high pressure created under the wing since the air can no longer displace downward creates more lift thus reducing your AOA for level flight and thus your overall drag?
Have you done this yet? I realize this was done a long time ago - but I'd really like to see a ground effect demo on a dry lake bed with a "start threshold marker" then keep it off for as long as possible and just see how far you can actually go in GE.
I noticed that you pulled it up to get out of ground effect, and then might have grabbed some flaps? Gliders look amazing, but all I know about them, I’ve unfortunately seen on RUclips. I knew the basics before, but I really want to do it now. Great video, where are you flying?
I though a PA28, because the aspect ratio on a glider is already high and it becomes theoretically infinite if the wing has zero distance to ground, so if the aspect ratio is already high, there would not be much induced drag left to get rid of by ground effect.
We have plenty of drag - just everything is in perspective. We are used to gliding over long distances so when our L/D suddenly changes from 48:1 to over 100:1 it gets quite impressive what the ship can do! Thanks for watching.
Amazing! 25+ yrs as a professional pilot but zero glider time. Would LOVE to get my glider rating someday but I can see that the sight picture in the pattern and on final will take a LOT to get me used to it. You float, and float, and float, and ...............
I'm not a glider pilot, but isn't there hot air rising above tar, that can keep glider at the same level or even lift it up? I guess if glider has 1:20 gliding ratio and flies at 80km/h speed, 4km/h upward wind can keep it flying at constant speed.
Did you have wheel down all the time? If not it’s dangerous dropping the wheel and extending air brake over the runway. It distracts you from the final crucial actions at touchdown. I’ve seen accidents caused by pilots trying to lower the wheel in very late final having forgotten their checks on downwind.
And that is not relevant to the topic of ground effect, but is a factor of the air and its friction as it moves across the earth. Same thing happens with glaciers as they slide down a valley. The ice closest to the dirt moves slowest due to frictional forces.
Ok since everyone is explaining what ground effect is, let me unexplain it. GE or ground effect is the perceived effect that the ground has on your wings through the air. It also effects ground squirrels and other ground animals and insects. Similar to ground beef, ground effect is delicious and nutritious. Unlike chemical based effects, ground effect is non GMO and gluten free. Relating to aeroplanes in general, the ground effect is very important because without the ground, there's not many places to go really. I mean water looks like water everywhere you go. Also the ground holds the air on top of it. The downside of ground however is that it is often very hard and dusty. A really real comment... I love the look of the cockpit.
I see pelicans doing this over the waves sometimes it's incredible how how far they go without flapping once. Sweet demo!
I saw flying fishes gliding over sea for 20-30 meters without flapping anything, I thought I was dreaming.
Pelicans use ground effect and a phenomenon called dynamic soaring. When you see them pull up and turn into the wind before heading back down between the waves, they are gaining a very slight amount of total airspeed due to the different wind speeds in between the waves and at the wave crest where the air is being compressed. You should check it out if that kind of thing interests you. Rc glider flyers have managed to break the 500mph barrier using similar techniques but on mountain tops instead of ocean waves.
@Michael Nickname Yep. The real max airspeed number is actually higher than that but the point at which they take the reading is the slowest part of the circuit. The formula they came up with for calculating the max speed from the reading on the radar gun should put it between 560 and 600mph. The guys doing this are at the top of their game in regards to flight skills, building skills and aerospace engineering ability. ruclips.net/video/nv7-YM4wno8/видео.html
@@shmaknapublar thats right, there are some good clips on Ytube of the RC gliders doing this. I fly RC slope, used to fly RC helis and powered planes...which were great fun...but RC gliding is in a different league:)
I love seeing my favourite RUclipsrs in the comment sections of quality videos deep in the recommendations well
Ground effect is where the air below the wing is compressed and creates lift. It happens within the height of the wingspan.
Correct explanation, no effect on drag.
Real engineering made a great vid about this
K S thats not correct. Induced drag is reduced in Ground effect.
It does however effect induced drag
The air is not compressed. Compressibility of air is negligible under mach 0.3. Lift in increased and induced drag is decreased because of the proximity of the ground.
I was 40 years old, learning with a experienced instructor in an aluminium glider made in Chekoslovaquia ( Blanik) . I was aproching final and he talked to me and made me rest some time away from the landing field. Before the landing field there was a wired fence for cows ( in Bahia Blanca, Argentina ) . He then asked me if I think that we will managed to arrive with enough altitude to surpass the fence... I told him that I thought we would NOT ... He told me to try my best, and I did it. We flyed up to where the fence was and we were already beneath (the fence is 1,20 meters high). So we were flying less than that ( may be 0,70 meter.) I kept cool, knowing he was teaching something I didn't know. Just before the wire fence he said " just skip the fence and get down again" and we did it !!! ( I was absolutly astonished, gratefull
and very happy to learn in practice this theory.) Now I am 74 ...
Thanks for sharing
Ground effect is because the high pressure air created under the wings is sitting against the ground, creating a cushion :o)
RetroGamerVX it’s because the extra high pressure air caused by the air bouncing off the ground and striking lower surface of the wing, adds to the pressure differential between the upper and lower surface. Ie greater static pressure (on a surface) below. It’s not the cushion itself because weight is still acting downwards so it’s always explained by the differential.
No room for tip vortices.
Lol
Ground effect has nothing to do with a cushion of air. There is less drag due to WTV's being cancelled out by the ground below reducing drag. This is why airlines started adding Wing tip generators. They effectively reduce drag on the linear axis of the wing root allowing a more efficient wing
K. Bierman
Oh dear, quick lesson on aerodynamics.
The glider flies by accelerating an Ovid cylinder of air roughly equal to 1.4 times the wingspan.
This mass of air has the downwards momentum of the time the glider was in it, plus the wasted energy of the tip vortices.
Now, ground effect.
Close to the ground the air cannot gain a downwards velocity so the energy that accelerated the air down is no longer lost, plus the diameter of the tip vortices is reduced from the 1.4 span effective area.
So, saying the air under the wing (and more so in front of the wing) is somewhat accurate as it has the force of the gliders weight acting on one side and the ground pushing back on the other side instead of free moment.
Over water we call it the wave effect. a good way to beat radar and conserve fuel by allied bomber's in WW2.
Here we are, back with another episode of why the hell is this in my raccomendations!
Same
Yes, but that's cool
Lmaook
Because you watch and comment. RUclips's bot sees this a recommends again. 😉
Sand +ä
Soviet Union build huge aircraft on this effect, as far as I remember, they fly in 10-30m above ground or sea and lift amazing amounts of cargo.
Ekranoplan or Caspian Sea Monster
torbinzix1 “Ekran” in russian is a “screen”
@@torbinzix1 they also made the lun class ekranplan that is armed with with sunburn anti ship missiles
In Soviet Russia, ground effects YOU!
0:31 Hate it when that happens
Yeah that seemed kinda sketch
what does it mean "I flew 85W..." i'm not a native English speaker)
@@alexaxel504 85W is the callsign (let's say, the name) of another glider he flew a while ago...
Superb demo
That caterpillar on the windshield really held on for its life
Its a small cord
@@sebdan3992 dont talk shit
@@sebdan3992 its a running joke for years amd you ruined it
Lmao😂😂😂
damn glider jokes
I used to fly a Schweizer SGS 2-32 many years ago. Your aircraft has a glide ratio we could only dream about!
Great video, thanks for posting it, that really takes me back.
I am training on that aircraft currently.
Cool. How you doin now@@unfixedcarp8039
I saw competition pilots use this effect to approach the field, running low at high speed from 2 or even 3 miles out the runway. Very beautiful, but sometimes not so funny...
Jose Marmontel these finishes were discontinued for being too dangerous. There were fatalities, including among the spectators, who often gathered in front of the finish line to observe and take photos of the low flying gliders.
-Northern California, waiting for my 'ride', as landing glider was in G.E. too long. It raised tail, slid on skid, hit the restraint barrier chain link fence, damaging wing, far beyond end of runway. "No ride for you"... ;
Fast calculations: 24 sec over airstrip (before pulling up for landing) with speed decreasing from 75mph to 70mph gives around 780 meters flown. 75mph to 70mph is a loss of energy that is equal to 7.2m loss of altitude. THAT GIVES A GLIDE RATIO OF 106! Note that changing speed loss for eg. from 74 to 70 gives L/D 140 ;) but glide ratio is for sure bigger than 100 which is still awesome
Thank you. I wasn't looking for this kind of video but it was a random pop up in my feed and was very enjoyable to watch. I am now looking for a glider flight near me.
Some rainy day when you want to go for an hour-long flight while sitting in your living room, grab a drink and a snack, enter THIS pilot's name in your search bar, and pick one of his flights to stream to your TV. Some may find it boring, but I find it exhilarating. He slides through the sky riding lift from ridge to ridge, and covers hundreds of miles. There is no crash, no burst of flames, and no accompanying music, just the raw experience of glider flight in the amazing Rocky Mountains. The beeping of his barometer is an emotional thing, triggeringbexcitement when chirping a high tone and concern when making a low tone. It sounds out if the glider is rising or sinking. On a good TV , you can see the gauge at the upper left of his dashboard, which also shows graphically his rate of climb or descent.
@@logmeindangit I've been there for a few days. Random video, now contemplating a demo ride and getting licensed. Club 30 min away. Had no idea flights could go so long, so high. Tonight searching for solutions for a full bladder...lol
I flew out of Estrella SSE of Phoenix and LOVED practicing high speed low approaches. Turning base and final from 10 - 15’ off the deck at high speed. I was flying a Grob 103 (57.5’ wingspan) so you would have to pop up to make the turns and then push it back to the deck. Serious fun.
It was my understanding, that ground effect is created when the wings are close to the ground, they create a high-pressure Zone using the ground to push back a force to the wings, making them more efficient compared to open air.
Nope ground interrupts wingtip vortex that causes induced drag to be reduced.
@@SVSky interesting...🤔 but I will look into it. I would compare it to how a dolphin surfs a bow wave.
This is great! Thank you. One thing though: ground effects are not a reduction in drag. The air flowing between the wing and the ground flows according to the Venturi effect, increasing air pressure under the wing. That's what lets you float.
this is why they built the ekranoplanes... right?
@@ВиделиЗнаем-б8б да абсолютно!
@M. Vendel commies.
@M. Vendel Communists. From the Soviet Union.
Awesome save with the landing gear!! 2:37
I've been binge-watching your videos and the way you handled and control your girl is damn impressive! 99% of people who drive are nowhere near 'as one' with their cars as you are with her. It is a pleasure to watch.
Birds skimming the water is the best demonstration of this effect.
i have some flight time in a mooney. exceptional airplane but due to the ultra efficient wing, they just dont want to land. there is some technique involved to land in a reasonably short distance. they get into ground effect and want to keep flying.
EZ VIBE is it just me or do gliders scare the shit out of other power driven A/C pilots?
EZ VIBE also, I would be interested to hear about the technique required to get that Mooney on the ground☺️
Thank you for sharing your experience! :)
@@adamey5935 Get the aircraft into reversed command flight when on the final leg; that is, nose high, high power setting slow flight. Reduce power and slowly pull up to lower speed until you both lose speed and altitude. At this point you're in reversed command. Add power to maintain your desired sink rate and watchout your speed, you don't want to stall.. Regulate speed with elevator input and sink rate with engine rpm (power).
just to clarify...there is a technique to landing in a reasonable distance, but i never got it. lol
I think ground effect is a cushion of high pressure air formed between the wing and the ground. The wing itself has the same drag, but induced drag is lowered.
I scrolled down to see if someone explained this properly and this is it, to see the effect vividly google Ekranoplan ruclips.net/video/V8Nu94khHoo/видео.html
Amazing!!! and the guy applauding for you at the end of the runway is the icing on the cake!!!
Outstanding gliding technique I must say sir, the aproaching to the runway was so smooth. You could land the moon!! Greetings from Catalunya!
Nobody can land the moon with a glider. Nobody did land the moon anyway. Ever.
On a side note - The legend goes that the Buccaneer can actually ride on its own shock wave at low level, and naturally stays at the height where the pressure from the wave counteracts any tendency to drop lower - this ground effect was about 18 ft and it became the operational height for interdiction at over 600 knots.
A USN admiral who had encountered the Buccaneer during joint Nato naval exercises previously and remembered the welcome they got as the USN fleet came into British waters. A flight of 4 Buccaneers went out as a welcoming party and requested permission to do a fly by "over" the US carrier.
Permission granted, nothing airborne over the carrier, all clear, now fly bys were usually a tight formation pass over the ship or fleet, not this time, the four ship Buccs split to send one down each side of the carrier at deck height, the other two straight along the flight deck at very low level and high speed and if accounts are correct, one did the pass inverted.
Years ago, Boeing had a huge cargo plane on paper, perhaps even built a prototype, called the Pelican that flew on this principle. The intent would have been to move many tons of freight over the ocean,
flying twenty feet or so over the water in a huge plane that would require very little fuel, with a range of many thousands of miles.
Wasn’t that a Soviet experimental plane? Think it was called the Caspian Sea Monster.
That was an old soviet design to carry troops, tanks and perhaps even short-mid range nuclear weapons to American shores, you can still see one of the devices sitting in a yard near Moscow, rotting away...
It was a failed experiment.
@Kade Roder I meant that Soviet ship was a failure and never entered service.
I remember an article in Popular Mechanics about the Boeing project. They usually design them to fly at higher altitude to cross land and other obstacles.
The wash that goes over the trailing edge of the wing is deflected by the presence of the ground effectively reducing the angle of attack which naturally reduces induced drag. That is what ground effect does. I had to explain this in depth for my CFI check ride.
ground effect is a long nice cruise into a short stall
See ground effect wiki for more detail. "This is caused primarily by the ground interrupting the wingtip vortices and downwash behind the wing. "
lol
Oh boy... I'm so looking forward to learning to fly next year. Great videos, Bruno!
How is it going now??
Great demonstration! A friend of mind found out the hard way, he came in to land too fast (in a Schweizer 2-22) and he flew over the whole landing strip until he pulled up at the end of the strip, stalled and fell like a flyswatter.
Can you calculate the reduction in induced drag in ground effect? The ASW 27B will do a 48:1 glide at altitude, but in ground effect with, maybe a 10% reduction in drag...53:1 ? For those who might not appreciate the performance of these sailplanes, that runway is 6300' long! Great demo Bruno, thanks
George Dyer knocks out trailing vortex drag (induced by lift generation from wings)
Easy to calculate if you know the height above the ground relative to the wingspan. At a height of half a span above the ground the induced drag is reduced by about 8%. At a quarter of the wingspan it is reduced by about 20%.
Great demo. Ground effect is a beautiful way to maximize flight efficency.
That is pretty amazing. I thought you were going to run on a dirt runway because you were so low already, and without lowering landing gear.
2:36 the magic begins. That is so sick haha. Nice demonstration man!
You should have titled the video "Ground effect, with NEAR MIDAIR FENCE COLLISION !" :P
Haha - I knew it was there. Thank goodness because it was hard to see so I was glad to be looking for it. Thanks for watching.
Subscribe me
Many years ago for my birthday a friend gave me a $50 gift certificate for a tandem flight, at llano ca.
It was great, it sounded like we were a jet instead of a prop job, the instructor said do you want to do a loop, and without hesitation said sure he said watch the G- meter in front of me, we pulled 4.9 G's .. I could almost imagine now how military fighter pilots must feel, then the landing was scary because he came in just like this guy scrapping buts as I felt! I never never been that close to the ground on a landing ,and I hoped this guy knew what he was doing!
Loved the experience!
So I purchased a gift certificate for my dad and he loved the shit out of it!
This is a bucket list thing , do it if you can!
I've also skydived 30 times in California City!
Bruno, would you shoot a short video looking along the wing trailing edge showing what each of the flap positions looks like? I'm kind of wondering if 1 and 2 are reflex and just how deep landing flaps are.
Should have started at maximum 60 knots instead of 80! My usual ground effect demo is to do a standard approach to the start of the runway at 55 knots (in DG1000) and then at the last moment close the brakes and cruise on down to the far end of the runway.
I hear ya - I actually had never tried this before so I didn't know how far down the runway I would get before the speed bled off. I was shocked I only lost 5 mph over that mile. I was totally expecting to bleed off at least another 15 during that time. Modern sailplanes still amaze me even though I have a lot of time in them. Fun stuff. I'll try the 60 knots at the end of the runway next time. Take care, Bruno
"That was fun" aka that was close to dragging a wing into a light pole!
Very cool. I had no idea of this effect, and how it plays out in reality. And while I'm not anyone trained in any sort of flying business, I find it very enjoyable to watch a video of someone doing something that they're obviously very good at.
When the floor is lava and the glider knows it.
Thank you Bruno for this informative video. I was surprised at the distance you glided at that low altitude. I thought for sure you would touch down short of the runway threshold .
Just shows you how amazing modern sailplanes (gliders) really are! I had so much confidence in what the ship will do that I was willing to put my butt on the line to show you. Go take a glider ride and see for yourself. You will be amazed! :) Thanks for watching.
Great demo. Cool shadow at 1:47. I was about to correct you: You said ground effect decreases drag. I always thought it increased lift. Some online research tells me that it does both. It decreases wingtip vortex and lowers the angle of attack of the wings slightly. I guess I'm a bit of an aerodynamics nerd.
Scott Gaul Yes you are and we're grateful for it.
When an aircraft is flying at load factor 1 (unaccelerated flight, as in not manuevering) the lift produced is always equal to the weight of the aircraft times the cosine of the flight path angle. Flying level in ground effect you have exactly the same quantity of lift as you would at 1000 feet, with considerably less induced drag.
The actual physics concerning ground effect are quite simple: Above the wing is a low pressure area, below the wing is a relative high pressure area. What happens in flight is that the air will want to move from the bottom to the top over the wings edges. This is why you see vortices around the wing tips. It is also why planes have winglets at the wingtips. To prevent this air from rolling from underneath over the wingtip to the top. Whenever you get close to the ground, this rolling motion is interupted by the ground, therefor acting as a sort of winglet. So no, you're not decreasing drag, you are increasing lift, which makes you put more downrudder in to maintain altitude, therefor maintaining a lot of your speed. I'm oversimplifying this effect, but in a nutshell that's how it works.
Flyingdutchy33 the wing in ground effect doesn't produce more lift. If it did, the glider would accelerate away from the ground. This is a fundamental topic: if we are flying level, we are always producing exactly the same amount of lift regardless of speed, altitude, etc.
I read it also squishes wingtip vortices making them actually bare against the surface and create lift
Ground effect is created by the turbulent air from the tip of the wins call vortice, this air hits the ground and bounces back to the bottom of the wing creating a cushion
Great demo. I understand well how ground effect works. Same for Helicopters. But I am curious about your saying drag is reduced during ground effect. Perhaps I should google as you suggest. :)
Edit. Just googled it. So much for my comment "I understand well.." LOL. So much more to it. I soooo love physics. :)
Drag will be reduced. You need less AoA to maintain lift to staying in air. This reduces the drag. Of this reason the ekranoplanes were inventet . Look in Google vor russian Caspic Monster .
Dude would’ve made a great U2 pilot.
You were the pilot in command and you refer to ground effect as magical. You know downdrafts and micro bursts are just angels farting.
Really? If an angel farted it would blow you out of the sky. People underestimate angels!
Hopefull Sinner even unicorns are rated higher tha angels these days...
That’s nutz how efficient that glider is in ground effect! 👍 Cool demo.
The higher the ratio between the induced drag and the parasite drag, the more helps the ground effekt. When a glider ist flying fast, he has a low ratio between the induced drag and the parasite drag, so ground effekt can't helb very much. I think the main reason for your 'ground effekt' is the updraft of warm air above the hot runway and only a little bit of the real ground-effect.
Can you repeat the same experiment at a time, when the runway has exact the same temperature as the environment? Perhaps at 7 o clock in the morning or so?
I was just thinking the same thing
It would work even better with the cold dense air providing more of a cushion/layer between the airfoil and the ground.
Good that you had the speed to pop up and deploy the wheel ... I guess you were really close the ground! Hey, maybe you can answer a question I've not found the answer to. When do you raise the wheel on take-off? Do you wait until you release from tow, or do you do it earlier? So far the two gliders I've flow have fixed wheels (still call "wheels" on my landing checklist, of course).
Not someone on the ground to take video, that would be a good comparison.
There really is a ground effect! I knew it!!......LOL. Great demo Bruno. Thanks for bring us along again!
And when you apply this to the undertray of a race car, you get crazy downforce with virtually no drag penalty!
Ferrariman601
Ferrari..Eh?
F1
Wrong. If this happens to a racecar they take off towards the sky, do some fancy flips and crash in a very bad way. In a race car, u want the complete oposite of this effect - Not a cushion of air on which you can ride, but a low pressure area, close to a vacuum, to suck you on the ground generating douwnforce and grip.
The Lotus T79 used ground effect to create more downforce.
It has the same name, but they're different concepts.
@@spookyshark632 Correct, the ground effects in the Lotus utilized the low pressure under the car and accelerated the air flow in order to increase suction towards the ground.
Well, it's also going to help more by being over the paved runway versus the ground. There is a much, much higher temperature coming up off the black tarmac then it would be from the ground.
Ekranoplan fly that way
That was nuts :D loved seeing that low fast approach . . . what a blast
This is what also happens when a playing card is dropped flat on a flat table. Maybe an inch or so. I guess
methinks any "chaffcutter" engine powered aircraft pilot should take note.
Firstly - there is no "go around" option.
While yes, the "glide angle" differs ... Learn to bring any aircraft to a safe stop on whatever,any flat ground within the glide angle.
It's not less drag, it's more lift.
Joe Matthews can’t tell if you’re joking or not.
How is it more lift if he is constantly floating and not flying? The cushion of air underneath the wings exert high pressure,so there's less drag.
Tasin Al-Hassan there is no cushion of air. It’s the wingtip vortices being disturbed and not allowed to progress and develop that is happening here. It’s only a decrease in drag.
+@@SidestickPilot Can you show me a diagram or anything that'll help me visualise this?
Tasin Al-Hassan google or RUclips Bold Method ground effect. Bold method explains everything very well they have diagrams and short videos to show the decrease in drag due to disturbance of the WTV’s.
Ground effect is pressure build up between the wing and the ground, nothing to do with making the wing more efficient/less drag.
Please do a vid about the funny hat all of the glider pilots wear!
@juggliar A skull cap would be useless and a sombrero would be overkill.
We all own one, i think gliding reduces your dress sense if I’m being honest
Right? It's everywhere, yet I've never seen any comments on it
I have a video on my channel demonstrating the Schweitzer 1-26 in ground effect. Despite being a low performing stubby little thing, it floats like a hovercraft in ground effect.
Perfect stop though, good call stopping when you did.
I started training in a Katana, which is just a motor glider with the wings clipped. It would float FOREVER on a warm day. I found it annoying. Love it when I transitioned to a Skyhawk, and it would actually land when I told it to.
You really shouldn't be wearing your dive watch, when flying ; )
Haha - I need to know the time every once in a while. ;)
Rolex Submariner or Deepsea?
@@randy3228 he no answerin
Much, much more intense than I expected - Awesome!!
perfect...real perfect
why do people enjoy nonsense like football when such stuff exist.??
Yeah...higher order of thinking when you know kicking and throwing a bag of air is wasteful to watch. Don’t get me wrong...I still like a good competitive football game but let’s not leave our brain to waste on fanatical TV games
Brian Xavier because football is easy to join whereas gliding requires more skill. Not saying that football requires no skill just the entry level of skill required for is gliding is much greater that foorball
You can enjoy both...
Brian Xavier To answer your question...... people who love to live life to the fullest do this...... glider flying. I did it years ago.
I'm getting back into the saddle at a nice young/old age. Nothing like it!!
Brian Xavier Luckily there are useful sports like soccer too.
Hi Bruno, i am wondering which flap settings u do on 2:36, i guess 1 to 3 to 5 (Landing), and i would like to compare this to a 20A. Because, on the 20A Flappossition 5 (1st Landing Position) you should push the nose noticeably down. You do this anyway, but i guess very slightly, also not as intense as it should be in 20A. What do you think?
Hi Roland. I love the 20! you are a lucky person to own one. Congrats. I pop up out of ground effect to adjust the flaps because I would never want to adjust them down so low. I initially move them down to thermal flap and then a few second later down into landing flap. The 27 only has one landing flap while the 20 has two. Consider me putting it into the less aggressive 20 landing flap setting at the end. Hope this helps.
“Lower drag” wth lol
Nephi Utah? Didn’t Tucker Gott go through Nephi during the Icarus “race”?
Yep Nephi - no idea on Tucker.
Quelqu'un peut m'expliquer svp ?
En gros il nous montre « l’effet de sol ».
Mais si tu n’as jamais piloté un tout petit peu tu ne peut pas vraiment comprendre...
Alexis Beuve Ducoup c'est supposé montrer quoi ?
illyonka que la portance augmente et que la traînée diminue.
La portance c’est la force qui pousse l’aile vers le haut
La traînée c’est ce qui freine ton avions ou ta voiture
Alexis Beuve Ah ok merci :)
@@alexisbeuve8199 Portance, c’est “lift” et traînée, c’est “drag”, n’est-ce-pas? Je ne savais pas les mots en Français. Merci!
Loved doing this in the IS28-b2 and hornet206 very long high speed run up the field to the hangar, 30 foot incline over 1 mile, was always the highlight of a long days flying.
Можешь не искать, русских коментов тут нет
Блин я искал ,не Русских даже а Башкирских)));)билат был кайда оса ,тормозга бас исер)))я так мысли в слух)):)
Нашел
Blyat
А в чем прикол? Не понял, это он про градиент ветра чтоли?
Ой не пи3ди , да
You can skip off of the ground like a flat rock on water, or in space travel, like aerodynamic landing modules that enter the atmosphere of a planet and need time to shed airspeed.
Am I a nerd if I think that's cool?
This can be pretty annoying when trying to spot-land an RC model. It's like the model is fighting you. Sometimes the plane can skim so far it's airspeed decays to its stall speed, and you just Bobble for a moment, then mush through the cushion with a thud!
Нихрена не понял что произошло
Drag won't be reduced. The air under the wing can't be pushed down because the ground is there, resulting in more lift.
question: est-ce que le fait que la piste est plus chaude que le terrain autour, fait que le planeur a de la "portance"??
Don't have as much drag as the usually do? Isnt it much more the effect that the high pressure created under the wing since the air can no longer displace downward creates more lift thus reducing your AOA for level flight and thus your overall drag?
With only metres left. Well done. Good demo.
Have you done this yet?
I realize this was done a long time ago - but I'd really like to see a ground effect demo on a dry lake bed with a "start threshold marker" then keep it off for as long as possible and just see how far you can actually go in GE.
You are without doubt a great glider pilot.
So is this is in part a result of the hot air coming off the runway creating a thermal lift?
The Spruce Goose , never flew on it's own. It took advantage of Wave Effect to get out of the water. It never got more than 20 ft AGL over the water.
I noticed that you pulled it up to get out of ground effect, and then might have grabbed some flaps? Gliders look amazing, but all I know about them, I’ve unfortunately seen on RUclips. I knew the basics before, but I really want to do it now. Great video, where are you flying?
I though a PA28, because the aspect ratio on a glider is already high and it becomes theoretically infinite if the wing has zero distance to ground, so if the aspect ratio is already high, there would not be much induced drag left to get rid of by ground effect.
We have plenty of drag - just everything is in perspective. We are used to gliding over long distances so when our L/D suddenly changes from 48:1 to over 100:1 it gets quite impressive what the ship can do! Thanks for watching.
I suppose the sunny weather has something to do with it, like for example the air density over the hot runway or something
Did you land in Minden ?
where was this done ? what airfield is that? looks like a blast !!!
The drag on the wings does not change. The pressure under the wings does, I believe.
Amazing! 25+ yrs as a professional pilot but zero glider time. Would LOVE to get my glider rating someday but I can see that the sight picture in the pattern and on final will take a LOT to get me used to it. You float, and float, and float, and ...............
I'm not a glider pilot, but isn't there hot air rising above tar, that can keep glider at the same level or even lift it up?
I guess if glider has 1:20 gliding ratio and flies at 80km/h speed, 4km/h upward wind can keep it flying at constant speed.
Did you have wheel down all the time? If not it’s dangerous dropping the wheel and extending air brake over the runway. It distracts you from the final crucial actions at touchdown. I’ve seen accidents caused by pilots trying to lower the wheel in very late final having forgotten their checks on downwind.
Very impressive. If you had "kept going for miles" could you have climbed with that airspeed enough to circle round and land?
La piste noire y est-elle pour quelque chose? vou vous posez après les bandes blanches hasard thermique?
Wind speed decreases as you get closer to the ground, because of friction. Characteristic property of convective currents.
And that is not relevant to the topic of ground effect, but is a factor of the air and its friction as it moves across the earth. Same thing happens with glaciers as they slide down a valley. The ice closest to the dirt moves slowest due to frictional forces.
Ok since everyone is explaining what ground effect is, let me unexplain it. GE or ground effect is the perceived effect that the ground has on your wings through the air. It also effects ground squirrels and other ground animals and insects. Similar to ground beef, ground effect is delicious and nutritious. Unlike chemical based effects, ground effect is non GMO and gluten free. Relating to aeroplanes in general, the ground effect is very important because without the ground, there's not many places to go really. I mean water looks like water everywhere you go. Also the ground holds the air on top of it. The downside of ground however is that it is often very hard and dusty.
A really real comment... I love the look of the cockpit.
Bruno, you make me envious every video
I have landed in Nephi a number of times and that site picture sure felt uncomfortable compared to landing in a 172.