Floating like a butterfly on planes - the "Ground Effect"
Jan 2, 2016 | 3:07 pm
#1
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Floating like a butterfly on planes - the "Ground Effect"
Moderator note: This thread originated in the BA forum, then was subsequently relocated to the TravelBuzz forum. /JY1024, TravelBuzz co-mod
In this month's National Geographic interview with a butterfly expert, it says:
Has anybody experienced this on a BA plane? I cannot say that I have, but I will see if I notice it on my flight to FRA tomorrow.
In this month's National Geographic interview with a butterfly expert, it says:
Originally Posted by National Geographic
[Certain species of butterflies are] demonstrating something called the ground effect. It's an aerodynamic phenomenon that occurs whenever wings are near a fixed surface, which increases lift and decreases drag. If you've been on a plane as it lands, you may have felt a brief floating sensation. That's the ground effect
Last edited by JY1024; Feb 19, 2018 at 7:59 pm Reason: Added mod note
Jan 2, 2016 | 3:35 pm
#2
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I was on an AA from TPA to CLT that felt like this and there was a communal intake of breath when it felt like the plane wasn't going to touch down when we were a couple of feet off the ground.
I'm not sure it's a BA thing TBH.
I'm not sure it's a BA thing TBH.
Jan 2, 2016 | 4:56 pm
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Nothing to do with BA, its just aerodynamics.
When a fixed wing aircraft gets close to the ground (less than a winglength - maybe about a quarter winglength for a noticible effect) then additional lift is generated from the uplift of air passing under the wing. At this time its possible for the plane to fly at slightly lower airspeed than would be normally required to maintain lift.
Ground effect happens on take off as well as landing, its not as noticible though on take off (unless youre the pilot and try to rotate before youre at the right airspeed!).
This effect is sometimes used in actual water skimming craft.
When a fixed wing aircraft gets close to the ground (less than a winglength - maybe about a quarter winglength for a noticible effect) then additional lift is generated from the uplift of air passing under the wing. At this time its possible for the plane to fly at slightly lower airspeed than would be normally required to maintain lift.
Ground effect happens on take off as well as landing, its not as noticible though on take off (unless youre the pilot and try to rotate before youre at the right airspeed!).
This effect is sometimes used in actual water skimming craft.
Jan 2, 2016 | 7:43 pm
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This is an aerodynamic effect, but only one of many things that provide the forces on an aircraft. A pilot that neglects to flare will slam into the tarmac - ground effect isn't going to stop you. And saying that any floating effect you feel is directly/solely due to ground effect is way oversimplifying the many parameters.
Plenty of small-scale Wing in Ground Effect aircraft have been built - https://www.youtube.com/watch?v=svvfzETPmNg - and there have been proposed large scale adoption for aircraft the size of today's jets, though I don't see it happening.
Plenty of small-scale Wing in Ground Effect aircraft have been built - https://www.youtube.com/watch?v=svvfzETPmNg - and there have been proposed large scale adoption for aircraft the size of today's jets, though I don't see it happening.
Jan 3, 2016 | 3:43 am
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The trick about WIG aircraft is, that you need less wing to generate the necessary lift as you're flying in the ground effect, and that wing is able to carry an obscene amount of weight. On the other hand, your fuel burn is astronomical as you're ploughing your way through the thick air near the surface.
Jan 3, 2016 | 9:21 am
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Here's more than you'd ever want to know about ground effect.
https://en.wikipedia.org/wiki/Ground..._(aerodynamics)
https://en.wikipedia.org/wiki/Ground..._(aerodynamics)
Jan 3, 2016 | 11:25 am
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Jan 3, 2016 | 2:02 pm
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This is a very well known aerodynamic effect and one that Concorde wing designers perfected and harnessed to be able to land so smoothly at high speeds. All achieved long before complex computer modelling allowed wing shapes to be perfected like today.
Jan 3, 2016 | 2:05 pm
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