new wingtip design

As a non-scientist/engineer, it baffles me that we are able to build amazingly sophisticated airplanes, yet, as the lecturer demonstrates, there is a huge amount of confusion over how to explain why a wing produces lift, and many of our common assumptions are simply wrong, i.e., the reason(s) for accelerated airflow over the top surface (which intuitively has never made sense to me). Engineers designing airplanes are themselves still arguing over whether it's more about Bernoulli or the downward-turning force or Coanda effect. Yet, I'm still able to get from one coast to another at 35,000 feet traveling at 600 mph, while sipping coffee and watching a movie.

I've been flying airplanes professionally for close to forty years and sailplanes for fun. I spend a lot of time looking at the wing trying to understand how it works. In the end, I conclude it's all magic. I kinda like that.

On Fri, 27 Feb 2015 22:02:08 -0800, mmartin46 wrote:

I've been flying airplanes professionally for close to forty years and
sailplanes for fun. I spend a lot of time looking at the wing trying to
understand how it works. In the end, I conclude it's all magic. I
kinda like that.

I've never forgotten one cloudy day with a low overcast. I was in a car,
driving away from Heathrow toward Chobham Common, which put us directly
under the approach to Heathrow, when a 747 dropped out of the overcast on
finals. For a few seconds it was heading for us, grabbing the bottom of
the cloud and flinging it at the ground: it was like watching a waterfall
beneath its wing.

That sight made me realise two things: that a 747 really does weigh a
couple hundred tons and that the reaction from deflecting that huge mass
of air downward has more than a little to do with keeping it in the air.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On 2/28/2015 4:48 AM, Martin Gregorie wrote:
On Fri, 27 Feb 2015 22:02:08 -0800, mmartin46 wrote:

I've been flying airplanes professionally for close to forty years and
sailplanes for fun. I spend a lot of time looking at the wing trying to
understand how it works. In the end, I conclude it's all magic. I
kinda like that.

I've never forgotten one cloudy day with a low overcast. I was in a car,
driving away from Heathrow toward Chobham Common, which put us directly
under the approach to Heathrow, when a 747 dropped out of the overcast on
finals. For a few seconds it was heading for us, grabbing the bottom of
the cloud and flinging it at the ground: it was like watching a waterfall
beneath its wing.

That sight made me realise two things: that a 747 really does weigh a
couple hundred tons and that the reaction from deflecting that huge mass
of air downward has more than a little to do with keeping it in the air.


Agreed...and for the sake of pub discussions, I think it's entirely
sufficient. Where the explanation quickly becomes complex is when we attempt
to mathematically analyze lift, because so far no single approach numerically
addresses lift creation's entire problem. Bernoulli and Coanda are probably
the most commonly known "incomplete applications" among the pub set; both are
concisely eviscerated (more accurately, bounded) by Dr. McLean in his
conceptual assessment of each's ability to address the physical situation.
Anyhow, fun to contemplate for those so afflicted...

Bob W.

At 04:59 28 February 2015, Paul Villinski wrote:
As a non-scientist/engineer, it baffles me that we are able to build
amazin=
gly sophisticated airplanes, yet, as the lecturer demonstrates, there is
a
=
huge amount of confusion over how to explain why a wing produces lift,
and
=
many of our common assumptions are simply wrong, i.e., the reason(s) for
ac=
celerated airflow over the top surface (which intuitively has never made
se=
nse to me). Engineers designing airplanes are themselves still arguing
over=
whether it's more about Bernoulli or the downward-turning force or
Coanda
=
effect. Yet, I'm still able to get from one coast to another at 35,000
feet=
traveling at 600 mph, while sipping coffee and watching a movie.

A reasonable parallel is the dual nature of light, which can be treated as
both wave and particle. Both models
explain the result.

John Firth

Glider wings work on faith.

It's easy to have faith at 4-5000ft so the wings work well & soaring is
easy.

'Tis more difficult to have faith at 1000ft so wings work less well &
gliding is more tricky.

Much below 1000ft I lose all faith & land shortly after.

This assumes UK feet where 5000 is "High" not American / Australian / South
African feet where 5000 is "Low".

KN

At 15:36 28 February 2015, John Firth wrote:
At 04:59 28 February 2015, Paul Villinski wrote:
As a non-scientist/engineer, it baffles me that we are able to build
amazin=
gly sophisticated airplanes, yet, as the lecturer demonstrates, there i
a
=
huge amount of confusion over how to explain why a wing produces lift
and
=
many of our common assumptions are simply wrong, i.e., the reason(s) for
ac=
celerated airflow over the top surface (which intuitively has never made
se=
nse to me). Engineers designing airplanes are themselves still arguing
over=
whether it's more about Bernoulli or the downward-turning force o
Coanda
=
effect. Yet, I'm still able to get from one coast to another at 35,000
feet=
traveling at 600 mph, while sipping coffee and watching a movie.

A reasonable parallel is the dual nature of light, which can be treated a
both wave and particle. Both models
explain the result.

John Firth