What is Flying?

The physics of flying by Newton

First published in 2001 in "Der wahre Grund des Fliegens", Germany

Each correct theory for a natural event is able to make predictions about essential phenomena of the event before experiments are done or/and using mathematics. Today's flight theories are only partial theories that cover laborious the area of flying. A basic theory for all does not yet exist. They would have prevented that a not insignificant number of people must die. Why? Only the right basic theorie for flying would have predicted that an aircraft must leave a wake behind itself. The correct theory of flight would have predict these wakes effortlessly. The following theory of flying by Newton would have prevented most of these accidents.

Is there a basic difference between general relativity and the Bernoullies theorie for flying? No: both arose from a moving point of reference, are victims of the general lack of understanding about the meaning of the terms
relative and absolute. The "heart of the matter" is by the nature very well hidden: most behind the terms absolute and relative. Absolute is true, relative false. For flying, there are three popular explanations that even in the pilot training are used. They are listed in http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html and evaluated as false. But an explicitly correct theory is not present, only a direction, where it can find, "between" Bernoullies and Newtonian physics.

What has gone down by today's mathematical science methodology is, that the mathematics of the observables and measurables of nature events does not necessarily lead to there inner physical functions. Even the mathematically precise calculations by epicycles for the planetary orbits in the middle age, for example, neither discovers, that in fact the earth orbits the sun and not vice versa nor that there is a gravitation. For the last first must fall an apple on Newton's head.
Only after, independent of the epicycles and later elliptical theories, Newton discovered the gravity, arised a correct understanding of the functions in the sky, these led to new and better formulas for the planetary orbits.

The state of today's aero "dynamics" corresponds unfortunately still only the mathematics of epicycles for planetary orbits, it is an only successful mathematics without the "heart of the matter". Physics is not, to can calculate the localized and measurable phenomena of natural events, but to find there basic physical principles of cause to effects. Especially of course for the phenomenon of flying, that can have only one basic prinziple for planes, bumble bees and subsonic and supersonic flight. In the following, the pure Newtonian theory is presented, fulfills all the above conditions: the understandable declaration, the universality and paths for formula creations.

According to Newton's laws can arise a force only when mass is accelerated kinetically. Therefore a wing can arise a force only by accelerating of mass. A plane takes mass of air and accelerate it downward. The reaction force of it is the force by the airmass. It is calculated with the accelerated air mass for every second. This mechanical process of flying by the laws of kinematics is substantially different to the previous paradigm that an aircraft flies by aero"dynamics".

Aero"dynamics" by Daniel Bernoulli describes pressure changes caused by changing the movements of air without flow of energy to or from the air. Aero"kinetic" is to change air movements by supplying energy. This is "the heart of the matter" of the Newtonian explanation of flying.
All objects, which can fly, flies aeokinetically!

The recoil of the air acts in principle at right angles to the surface, which moves the air. For flights every moving of air mass by an obliquely positioned plate happens according to the laws of the inclined plane, but with its bottom and the top. The bottom pushes air mass down, so arises a pressure at their surface. The top surface generates by its backwards sloping surface a free space. That leads to a negative pressure room, in which the air flows in from the top. The thus sucked-in air from above acts with their inertia as well as the one at the underside of the wing, where air is directly pushed. The pressures on the wings surfaces times there sizes results to the force of the wings by the air.
All processes of flying are kinetic actions with supply mechanical energy to the air masses. In all cases an aircraft requires more energy than it need to require only the sum of all drags. The energy remains in the air and inserted into the kinetic energy of the downward air flow. This downwash of air, generates by the wings, entangled with the air arround the path of a plane, so that arise the wellknown vortex street
s. These then decline more slowly than the air was accelerated directly by the wing (during only milliseconds!). The mass of the wake turbulence street has increased because of its involving with ambient air. But so, as arises vortices on the right and left side on the flight path caused by the downwash, arises vortices also at the front and rear edge of the flight path. At the starting point arise the starting vortex and with the forward movement wings around them the so called profile-vortex. The last was in the Bernoullies theory in ignorance of why it arises, denoted with a "fictitious circulation". But by this very real profile-vortex arise the paradoxical increase of air in front of a plane and the appearance of a faster running fair wind at the top side of the wings. In supersonic flight, there is no more a profile-vortex. In sum, an airplane makes it with the air like comparatively a quick moving flat stone on the waters surface with the water, where it leaves a ditch in the water, which will closed behind the stone by the high swelling water on the sides, so that also arise a vortex street in the water.

An airplane "rides" on its accelerated air mass, the downwash

The line arrows shows the really given motion vectors of the air by the wings: the downwash
. Physically it is not required, that a wing has a particular profil. But for the efficiency and flight safety wing profiles are of paramount importance. By this physical function arise theoretical the basic formula for the lift force out of the armchair without any experiments in the wind channel or elswhere.

The required mass per second, the downwash, arises in that area, which the wings per second in the air sweeps over times the velocity to which the air from the wing is accelerated downwardly.
The velocity, which the wings gives the air mass downwards, is calculated by the geometry of the oblique position of the wing. With a flat plate as a wing profile results the velocity of the air from the forward velocity of the plate and the angle of attack α according to the laws of inclined planes. A cambered airfoil profile must be replaced by suitably equivalent flat plate, converted by calculation or experimentally.

For the calculation of the aerocinetic lift force arise the following kinetic basic formula, arises by Newton's principle of generation force by change the momentum not in the version force F = m times a, but F = m(dt) times v:

L = ρ At v2 (sin α)2 (cos α)2 1 [ s ]

L = lift force as the vertical component of the recoil force of accelerated downward air masses.
ρ = density of air
At = the area which swept by the wings per second, so span of wings times velocity of wings.
v = velocity of the aircraft relative to the air
α = angle of attack of a plate as wings

The formula above arises from the basic principle of flying. But with a basic principle alone cannot be "fed" a technique. For example, by the physical basic principle of a camera results the so-called pinhole camera. In place of the lens there is only a small hole as the fundamental physical principle. The optical imaging of objects is only, that  a light beam goes straight. So each point of an object rectilinearly come through the hole to the rear wall, and there appears a geometrically precise light image of the object. However, the size of the hole should be small for high sharpness, but large for high light intensity. Since both are required simultaneously, a pinhole camera is unusable. The technology placed in a big hole a lens, which deflect the light rays from one object point, which do not go through the center of the lens, also to the center beam. For technology and usability the lens of a camera is in the foreground, as well how for flying a wing profile, even though also it has nothing to do with the causal physical source for flying ability. But it improves the flight performance such as flight safety and superimposed therefore the physics of flying. Out of any type of an airfoil it is therefore not possible to read out the cause of why we can fly.

This basic formula is not suitable for construction an aircraft. E.g. the width of a wing is not included. Physically it is also not relevant, but technically exists influences, who have nothing to do with the physical principle, nevertheless by narrower wings leads to lower lift force. For school and for existing aircrafts the formula gives approximate values. For the technology other formulas can be used which relate to the geometric dimensions of aerofoils. But: technology is no physics!

This physical formula correctly reflects what are the changes by its contained basic physical variables of air like density, air speed and angle of attack. For example, lift is proportional to the angle of attack and proportional to the air density (high altitude airfields) and (with constant angle of attack) to the third power of airspeed (so that unacceptably high rate of speed decomposed each aircraft). The latter can be realized only in a wind tunnel on a fixed wing. An aircraft in the free airspace can not increase his speed while maintaining the angle of attack, it will rise up and thus impinge the air with decreasing angle. Therefore the forces on a wing of a free flying plane arise only with the square of the speed.

Nature processes are basicly determined by cause to effect principles. The direction of cause to effect is determined by the direction in which the energy flows, which is need to require a process. A plane for its flying must deliver energy to the air. This also applies when a bird "flies" in an upwind with optically stillstanding to the earth. It represents the conditions in the wind tunnel, where it seems, that the energy comes with the air. Despite this outward exchange of the movements the flow of the needed energy remains by the same: the energy always flows from the wing to the air, so that arise a reaction force from the air to use as lift. For technology is allowed to see it oppositely, because the quantitative values ​​remain the same, but physically it is wrong. The energy from the rising air during a "stand"-flight can use a bird only as driving energy. In all cases, regardless if wings or the air moves, wings must bring energy into the air to create lift force. The same applies for the wings of a wind turbine. The wing of a wind turbine works like the wings of a plane in nosedive flight. The generator of a wind turbine is the brake for the plane. The braking energy is converted to electrical energy in the generator. The technology means that the wind provides the energy. The calculations leads to leads to quantitatively correct results
, but not with the "heart of the matter", the correct physics, of this natur event.  The wind gives the wing only the propulsive force, with which the wing produce the lift force, with which the wing drives the generator.

Now an animation shows the original procedure
of flying by a moving wing. Two air particles in front of the wing, positioned at the appropriate place, shows how the air in the near region to the wing is moved. It moves with an forward up, then back and at last only downward swing. This shows the basic physical principle of flying: air masses accelerate down to emergence of a recoil force by the air on there a plane can "ride". How a wing does that in detail, continuously or rhythmically with slapping against the air is a technical matter. The swinging of the air on the place, where the wings profil is moving through, is a detail, which is important for the technology, but not for the physics. To find a correct theory of natural processes out of a few of details is not possible. Natural events can be decrypted only in their entirety.

In the animation two air particles shows the absolute movements
of the local air relative to the still standing surrounding air on each area where a plane flows through, which not have been without a flight through of a planes wing. Only these air movements, generated by the wing, are the reason for flying and are therefore the "heart of the matter" of flying.

Everything, that is presented different to them in media, pilot training, encyclopedias and universities
is definitely wrong!

A science physics must say right and wrong, otherwise it is not a science, because that is their basis of existence. The rightness of a physical theory is not confirmed by either one or a majority of experts nor by experiments of parts of the whole event nor even by quantitative results. It confirms exclusively by compliance with the criteria for physically correct theories which are: boundless universality without any exception by a basic principle (for flying only one for aircraft to bumblebee and sub​​- to supersonic flight), the answerability of all questions for all things standing issues related to flying without even a single exception, and without external help directly with only the basic principle. A lot of questions are: Why is there a ground effect? Why a ceiling effect? Why carry two wings of a biplane not twice? Why swells the air up in front of a wing? Why not at the supersonic flight? Why around the whole bumblebee wing? Why is there a wake vortex behind a plane? Why it drops down? All this and more can be answered directly from the basic principle and arise to mathematical formulations. These are much easier without help by other external events. And the theory of flying by Newton saves a lot of wind tunnel tests.

The movements of air, shown by the particles in the animation, leads with its parts in the flight direction to the drag, with its vertical parts to the lift. During a vertical dive alone the drag is the lift (but of course not enough). The only reason, to can fly, is, to accelerate an air flow downward by
inputing of energy.  

Wind blast is no flow, only on the air visible movement of an aircraft. To this apparent motion of the air is added by the Bernoulli theory the top red marked truly movement of the in the animation. The latter arises by the air moving up in front of a wing. This air (the profil vortex) moves at the top of a wing rearwardly. The Sum of both arises out of two different coordinate systems: of a relative movement of air in the coordinate system of the moving aircraft and the red marked real motion of air based on the surrounding air in rest. But, additions of values ​​of physical movements out of differently moving coordinate systems are physically inadmissible. The downward accelerating air by a wing is totally ignored by the Bernoullis theory. It shows itself in the wind tunnel through the gently sloping stream lines only behind a wing. Also, an improvement of the Theory Bernoullis theory is false, that a "flow" would be diverted, although with this arises quantitatively correct mathematical results. Nevertheless is it physically wrong, it does not contain the "joke of the matter" of flying.
The wrong Bernoulli theory is also accepted, because the pressure distribution over the length of a wing profile looks exactly as if an air flow passes through a constriction. "As if": so one can be fooled. If everything in nature would be so, how it looks, the physics would already be completed and it would take no longer to train physicists.

Nevertheless in the pressure distribution around a wing profile are contents parts of pressures influences by the Bernoullies effekt, arised by the real movements from the profile vortex. Therefore the Bernoullies theory seems plausible. But, the purely resulting pressure changes caused by the movements of the profile vortex added up to zero around the profile. The Bernoullies effect caused by the profile vortex contributes nothing to the lift (but  with influence to the momentums that want to twist a wing and to the center of gravity location). The profile vortex is an air movement, induced only by the preceding arising of lift force. It is a consequence, not a cause. In supersonic flight, there are these swinging movements of the air above the wing not more exists, nevertheless the plane is flying. Even a plane would fly just as well, if it did not give an Bernoullies effect! A viscosity of air is unnecessary for flight too.

What is the general physical accurate and understandable explanation for flying?

Each flying object keeps up itself by accelerate air masses downward

Aircraft, helicopters and birds do that with and through their wings with an angle of attack and their steady forward movement. Insects and birds during its starts do that periodically with short wing beats with much higher angles of attack. The force from the air to the wings influences principle perpendicularly to the wings surfaces, one of three fundamental laws of aerokinetics. At 45 results out of the drag a buoyancy component of 71%. This allows also the bumblebee to fly comfortably. The large vortices in relation to the wings of the bumble bee are the consequences and not the causes for arising of lift force on wings of insects. The cause of the flying ability is always the same: accelerate air down, no matter how. (The above formula for the steady flight is of course no valid for flight of insects.)

More about aerokinetics in www.flugtheorie.de