CENTRE OF PRESSURE

When an aircraft is in flight it experiences several loads across its structure which is defined as pressure distribution in technical terms. The pressure varies across the fuselage and the wing structure and it is impossible to analyse it. Hence the overall pressure distribution is represented by a single aerodynamic force called center of pressure or total reaction force which lies on the chord line of the aerofoil. The center of pressure moves along the chord line when the angle of attack is altered.

At normal cruising speeds and low positive angles of attack the center of pressure is positioned on the chord line near the center of an aerofoil. With increasing angles of attack the center of pressure moves forward towards the leading edge and the magnitude of the total reaction force increases. When the aircraft reaches the stalling angle of attack the magnitude of the total reaction force reduces and the angle of attack moves towards the trailing edge.

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