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As we have mentioned earlier, wind shear is a natural phenomenon which involves abrupt changes in wind speed and/or direction over short distances. Wind shear can be encountered when flying through a temperature inversion layer. However, the dangerous wind shear we're interested in is generally associated with a frontal system, especially one which includes a thunderstorm.

During a thunderstorm, a large column of cold, dense air rapid

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What is windsheer?

2007-04-08 13:07

Wind shear is defined as a change in wind speed and/or direction within a short distance. It can be in either a horizontal or vertical direction, or both. This change causes a shearing or tearing effect, which causes great concern for pilots and airline industries.

The lift generated on a plane's wings is mainly generated by Bernoulli's Theorem. This states that as a fluid is accelerated, the pressure it exerts is reduced. This is the principle on which an airpl

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Flaps

2006-10-10 12:27

The other camber increasing devices, forming part of the inboard wing trailing edge in the Seafire photo, are the flaps . Plain flaps are also a hinged section of the wing – as in figures C and D in the aileron diagram above – but move only (and jointly) downward usually to fixed predetermined positions, each position providing varying degrees of increased lift coefficient and increased drag coefficient that the designer thought appropriate. For instance ? for one particular aircraft ? at 5?deflection there is a good increase in C_L with only slight increase in drag. At 15?the drag increase starts to equate with the C_L increase whereas at 25?or 30?the increase in drag is much greater than the increase in C_L; at 45?the flap is acting as an airbrake.

The change in camber caused by lowering flaps in flight, without ch

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The basic forces in normal flight-Drag

2006-10-09 16:45

Drag is the resistance of the atmosphere to an aircraft pushing through it and the resistance depends on:-
  (a)  the streamlining of the aircraft body
  (b)   i. the excrescences attached to the airframe
     ii. turbulence at the junctions of structural components
     iii. the cooling airflow around the engine
  (c)  the roughness of the surface skin
  (d)  the 'wetted' area i.e. the amount of surface exposed to the airflow
  (e)  the density of the air
  (f)  the velocity of the airflow
  (g)  the amount of lift being produced – which will increase as the angle of attack increases

These components of drag are classified in several ways and we will look at them in the aerofoils and lift module.

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The basic forces in normal flight-Thrust

2006-10-09 16:43

Action and reaction

In the Jabiru the engine supplies torque directly to the propeller shaft and the propeller converts the torque to thrust. We will amplify how this is accomplished in the engine and propeller module. Sufficient to say here that the propeller pushes a tube of air, with the same diameter as itself, backwards i.e. it adds momentum to the tube of air, and momentum = mass × velocity and is also a vector quantity. Increasing the velocity also imparts kinetic energy to the air. This tube of accelerated, energised air is the slipstream .

If you recall Isaac Newton's – whose name is perpetuated in the unit of force – third law you will expect an equal and opposite reaction to the action of adding momentum, and this reaction is application of forward momentum to the propeller, which pulls the rest of the aircraft along behind.

The line of thrust

We need to clarify the line of thrust. This line

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