An atheist is a man who has no invisible means of support.
John Buchan [1943]
John Buchan [1943]
Aerodynamic lift of a wing can be explained and calculated through simple application of Newtonian physics. Air flow following the contours of a wing in normal flight departs in a downward direction. In this redirection of flow, downward momentum is produced.
Upward reaction force (or lift) must be equal, according to Newtonian physics, to the downward rate of change of air momentum. Inclination of a lower wing surface deflects some air downward there, while greater downward deflection is produced as flow follows the downwardly-curving upper surface.
In the downwardly-curving flow, an upward pressure gradient exists which opposes atmospheric pressure to cause upper surface pressure reduction. Bernoulli's law is satisfied with velocity changes related to pressure changes when oncoming air accelerates over the wing leading edge into the reduced pressure above the wing and decelerates in encounter with increased pressure below the leading edge.
The pressure difference also accelerates air upward around the leading edge. These accelerations occur in accordance with Bernoulli's law, but the greater upper surface velocity is more easily explained as resulting from pressure difference, rather than causing it as popular theories teach.
As air is accelerated downward by wing passage, upward recirculation occurs all around the airplane, away from higher pressure below and toward lower pressure above. Thus recirculation occurs forward and upward around the wing, and laterally outward,upward and inward to produce twin trailing vortices which is made visible in smoke behind aerobatic plane wings at airshows.
Forward recirculation carries upwash into which the wing flies. Energy is recovered from leading edge upwash as circulation rounds the leading edge to produce centrifugal pressure reduction, known as "leading edge suction," and forward thrust. Leading edge suction is sometimes used to operate a stall warning horn.
Leading edge pressure reduction produces forward thrust on the wing, but curvature of circulation around the rear produces opposing rearward thrust. If these were equal they would cancel, but energy lost into lateral recirculation around the wing ends causes forward thrust to be less than rearward thrust.
The difference between these thrusts appears as drag, commonly referred to as "induced drag," because the classical mathematics treatment is similar to that of electromagnetism and electromagnetic induction.
When air flows past an airplane wing, it breaks into two airstreams. The one that goes under the wing encounters the wing's surface, which acts as a ramp and pushes the air downward and forward. The air slows somewhat and its pressure increases. Forces between this lower airstream and the wing's undersurface provide some of the lift that supports the wing.
But the airstream that goes over the wing has a complicated trip. First it encounters the leading edge of the wing and is pushed upward and forward. This air slows somewhat and its pressure increases. So far, this upper airstream isn't helpful to the plane because it pushes the plane backward.
But the airstream then follows the curving upper surface of the wing because of a phenomenon known as the Coanda effect. The Coanda effect is a common behavior in fluids--viscosity and friction keep them flowing along surfaces as long as they don't have to turn too quickly. (The next time your coffee dribbles down the side of the pitcher when you poured too slowly, blame it on the Coanda effect.)
Because of the Coanda effect, the upper airstream now has to bend inward to follow the wing's upper surface. This inward bending involves an inward acceleration that requires an inward force. That force appears as the result of a pressure imbalance between the ambient pressure far above the wing and a reduced pressure at the top surface of the wing.
The Coanda effect is the result (i.e. air follows the wing's top surface) but air pressure is the means to achieve that result (i.e. a low pressure region must form above the wing in order for the airstream to arc inward and follow the plane's top surface).
The low pressure region above the wing helps to support the plane because it allows air pressure below the wing to be more effective at lifting the wing. But this low pressure also causes the upper airstream to accelerate. With more pressure behind it than in front of it, the airstream accelerates--it's pushed forward by the pressure imbalance.
Of course, the low pressure region doesn't last forever and the upper airstream has to decelerate as it approaches the wing's trailing edge--a complicated process that produces a small amount of turbulence on even the most carefully designed wing.
In short, the curvature of the upper airstream gives rise to a drop in air pressure above the wing and the drop in air pressure above the wing causes a temporary increase in the speed of the upper airstream as it passes over much of the wing.
If one holds the back of a spoon in the edge of a stream of water running freely out of a tap (faucet), the stream of water will deflect from the vertical to run over the back of the spoon. The effect can also be seen by placing a can in front of a lit candle. If one blows directly at the can, the air will bend around it and extinguish the candle.
Manufacturer | Triumph Engineering Co Ltd |
---|---|
Also called | 'Bonne' |
Production | 1959–1983 |
Predecessor | TR6 Trophy |
Engine | Four-stroke Parallel-twin |
Power | 46 bhp (34 kW) @ 6,500 rpm (T120) |
Transmission | 4-speed (later 5-speed) |
Wheelbase | 55.75 in (1416.1 mm) |
Weight | 395 lb (179 kg) |
Related | TR7 Tiger |
Without doubt, as a tool for the dissemination of ideas the Internet sits next only to the printing press in its potential; yet just as Chesterton, I think it was, wrote that the downside of the printing press was the explosion of the volume of dud philosophy that appeared in its wake, so too does the Internet have a downside.
It is to be found in the outcome of Operation Algebra.
It is, of course, people who do bad things, and not the tools they use to inflict harm; no home would ever get built without carpenters using hammers, yet in the wrong hands there are few more lethal weapons. Just as the Internet is potentially one of the greatest tools ever created by Man for the spreading of The Word, people of faith have to acknowledge that great evil operates in it as well. We cannot shy away from this, as much as we would sincerely like to.
The real world is that of The Word. For the past 200 years, many of us have been trying to live without The Word. For the most part, our efforts have resulted in catastrophic failure, their fruits ideology, genocide, and the slavery of living from paycheck to paycheck. One day, we'll look back on this period in history and laugh.
‘I really don’t know why you’re giving this man a platform to make his wild accusations. You’d have been better off ignoring him.’
‘I don’t accept a word he says, I’m afraid, the man’s obviously unbalanced, I think I can make my own mind up ...’
‘James, what are you doing? XXXX by XXXX was thrown out of XXXX, he has no support except those who are so closely aligned to him that they have no choice but support him. Let it go, buddy.’
D---- calls me polished. Polished, because he knows me. Because he knows underneath that layer, I CAN be pretty cold booded and ruthless. Hey, I'm a salesman. Of COURSE I'm good. Think about it. Would a company pay me what they pay me if I wasn't????
Look, I'm good. Don't deny it. Damn good salesman. And I can't teach what I do. I can't. Of COURSE I have a strategy- the attack and lull strategy- but no matter how hard I try, no trainee can pick it up, you can either do what I do- you was born to do it- or you can't.
What wins is walking in thinking 'I'm going to close you down, mate. I'm going to cut off your options and you WILL do what I want.' I'm fairly blatant in my work. It;s WHY I'm the best. 'EVERYONE can be cozened or cowed, just pick your tool, but don't fuck up, because it really is, either or.'