Cambridge scientist debunks flying myth

Aeroplanes can fly because their wings cause the air pressure underneath to be greater than that above, lifting them into the air. But engineers have for years been frustrated by a theory which wrongly explains what causes the change in pressure to occur.

The myth is commonly found in school textbooks and aeroplane flight manuals, and is so widely believed that even Einstein was rumoured to subscribe to it. Now a Cambridge scientist has become so fed up with the bogus explanation that he has created a minute-long video to lay it to rest once and for all. The video, published on YouTube by Prof Holger Babinsky of the university’s engineering department, seeks to explain in simple terms why the myth goes against the laws of physics.

According to conventional wisdom the pressure change happens because the air on the curved upper surface of the wing has further to travel than that below the flat underneath surface, meaning it must travel faster to arrive at the other side of the wing at the same time.

In fact the real explanation is nothing to do with the distance the air has to travel. The curvature of the wing causes the change in air pressure because it pulls some of the air upwards, which reduces pressure, and forces the rest beneath it, creating higher pressure.

A law known as the Bernoulli equation means that when pressure is lower, air moves faster – so the air stream above the wing does move more quickly than the one below, but this is not what causes the difference in pressure.

Prof Babinsky proved his theory by filming smoke passing across a wing.

If traditional wisdom had been correct the smoke above and below the wing should have reached the front edge at the same time.

The video demonstrates that the explanation is fundamentally flawed because the plume above the wing reached the edge much sooner than the plume below.

If the distance the air had to travel was causing the pressure to change, then a boat’s sail – where the air travels the same distance on the inside and outside of the curve – would not work, Prof Babinsky said.

He added: “I don’t know when the explanation first surfaced but it’s been around for decades. You find it taught in textbooks, explained on television and even described in aircraft manuals for pilots.

“There is no law in physics which states when streams of particles start at the leading edge of the wing they should reach the tailing edge at the same time.

“I’ve even heard a story that Einstein drew a design for an aircraft wing with a long, squiggly line on top of an aerofoil to make the distance for the air to travel greater, but this would not work.”

Link to the Daily Telegraph story

The Manifesto



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The Manifesto…

We've tried to ignore the problem… I tried to ignore the problem. I wanted to ignore the politics of the internet and, in many ways, politics itself. From a netizen point of view, Democracy often seems inefficient and ineffectual. But just because WE want to ignore it, doesn't mean politics wants to ignore us.

There are many groups who would subjugate us if they could. They would force us to pay every time we heard a song on the car radio, they would make sure we can't speak freely about their brand or their brand of government, they would exert complete control over our online existence.

As Netizens, we naively think that calmer heads will prevail and this has often been the case… but laws like SOPA and PIPA, which could potentially make the Patriot Act look tame if used to their fullest extent… continue to be paid for by big industry and pushed through congress. These acts are not just bad, they are unAmerican and more akin to something we would see in China or Iran… not here.

How does this happen? It's simple enough, Congressmen are paid to make laws that would oppress us. In the emerging world, this would be called "Corruption"… here it's called "Contribution". It's easy. These laws are complicated and their most of their constituents don't even know that their congressmen are involved or how these laws would affect them. The industries behind these laws are wealthy and spend lavishly on representatives willing to support them. Most importantly… there is little to no political pain for these representatives. They fill their campaign coffers with cash… if the bill fails, they keep the cash and it's quickly forgotten. If the bill passes, they'll get more money next year.

This needs to stop.

We can no longer expect our representatives, many of whom couldn't write an email on their own, to represent us without firm action. We can no longer depend on OUR means of discussion – Facebook, Twitter, and Email -l to express ourselves.

We need to fight these laws, and the lawmakers that would pass them, in their back yard. We need to earn their respect, and fear if necessary. We need them to know that supporting these bills has a political cost.

We need a sort of "Internet Protection Fund", a PAC, that is designed for a single purpose – To use every legal means to attack those who would attack us. To bring the fight to to their doorstep, their airwaves, and their TVs. We need to organize and focus the resistance.

Step 1 – Stop the SOPA and PIPA before they are passed through targeted boycotts, information campaigns, and letter writing campaigns.

Step 2 – Target those in Congress who support these bills and attempt to unseat them in the fall with internet, grassroots, TV and Radio campaigns. Congress needs to know that supporting these bills is no longer a blank check…it's no longer safe.

Step 3 – We need to build our organization BETWEEN elections, build its resources, and build its capacity to defend our rights… aggressively. This fight is about to intensify as the information age matures. We need to begin to take an active role in shaping our online future.

This is not a replacement for organizations like the Electronic Freedom Foundation… without whom we will be already be in virtual chains. This is the sharp end of the stick that comes when they are not able to negotiate our freedom. These are the troops that back up the political discussions with real, tangible, action.

This is not a replacement for Anonymous. They play harder than we will. We will keep our fight within the confines of the current laws. We will use every means within those laws to express the will of those we represent but we will stay well within the confines of the current rules.

We will play by the political rules that our opponents play by… not the ones we wish they would play. We will use our skills, connections and ability to organize online but we will bring this fight to their field and beat them there.

So now what do we do?

Step one: +1 this post and pass it on. If there is enough interest, the next steps will be somewhat obvious (begin the organization structure). Comment and let me know what you think and what you would do next. If there is enough interest… more posts will follow.?

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