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There are gears slipping, alright, and it's not just SCOTUS: it is us. We shouldn't need them to tell us that bump stocks, silencers, automatic weapons of any type, etc. etc. etc., aren't necessary to living a happy fulfilled life any more than we should need a church to teach us right from wrong or what is moral or not. We are a sick, selfish, society unable by all evidence to collectively do the right things for the right reasons: cue up the original sin crowd and fire up the band. Hopefully in the future, when our fossilized remains are being studied, they won't be laughing too hard.

Because the shape of an airplane's wing is chosen to maximize lift over drag in a particular flight regime, as well as things like reducing shock wave formation, storing fuel, being strong enough, having a wide speed range etc. The wing of a Cessna 172, for example, is curved on the front, flat on the bottom and curved on the top, because that gives you fairly efficient flight at around 100 knots with a fairly flat cabin, and still has decent low speed performance and stall recovery behavior. But that doesn't mean that aircraft generates lift because the top of its wing is curved, any more than a parachute opens because it's made of nylon. The curvature of the top of the wing is a result of several other decisions, just as the use of nylon is the result of design tradeoffs in weight, material strength and elasticity. To be more specific, many aerobatic aircraft have symmetric airfoils, and can fly upside down as well as right side up. The Cessna 150 Aerobat (pretty standard airfoil) can fly upside down, although that's not recommended due to the lack of inverted fuel and oil systems. The M2-F2 lifting body was curved on the _bottom_ and still landed acceptably well without power. (The one famous exception became the opening scene for the Six Million Dollar Man.) What makes a heavier than air aircraft fly at the end of the day is simple physics; the aircraft deflects enough air downwards that the reaction to that pushes the plane upwards. (Newton's Third Law.) It can be done by brute force (quadrotor drones) or it can be done via a fixed airfoil that deflects air from the relative wind downwards. To get fancier, the deflection of air downwards is seen (when looking from the side) as the superposition of a steady state fluid flow (i.e. the relative wind) and a circulation (the deflection of air downwards.) The superposition of these two produces lift, per the Kutta–Joukowski theorem. That's a lot to tell a first time flying or skydiving student, so there's a simplification that I often used: The air on the top of the wing has to move faster than the air on the bottom of the wing due to the curve, and they have to meet up again at the trailing edge* so the air going over the top has less time to press downwards** - so there's less pressure above the wing than below, and the wing gets sucked upwards. That gets the basic concept across that I want to get across - that lift depends on airspeed, so without airspeed there's no lift, which is why stalling canopies can cause you to drop rapidly. It's not that accurate but it doesn't have to be for first time skydivers (or pilots.) And this simplification works OK, but will get you into trouble if you are doing things like designing aircraft or trying to figure out exactly what a ram air wing is doing. (* - that's called the Kutta condition, and is valid for most flight regimes for standard airfoils) (** - a really facile explanation of the Bernoulli Effect)

First the glands, then the drooling. Step back a planet or two for a better view and we won't seem any different.

It is usually stated in a very simplified form, only for the layer at the surface of the wing, as it could be calculated at the beginning of the 20th century. Hence the discrepancies. If you integrate for the entire volume of air affected by the wing (as is done with modern computers), then there will be no discrepancy. And the "lifting force" considered relative to the perpendicular to the direction of movement, as expected, will decrease sharply in all directions except for optimal horizontal flight.

Brent, you didn't read it to learn; you read it to find something that fits your narrative.

Dan It is allowed in an Icon container, the list you are referring to needs updating. It was a requirement set up by JAA ( the predecessor of EASA here in Europe. Besides, it's TSOed and any Rigger may or may not determine compatibility. Stefan Gardner : She looks fast ! Truman Sparks : Yeah, it's the stripes.