Why a car can outrun a helicopter

In the Grand competition for speed between what goes and flies, we usually unequivocally give the palm of aviation for one simple reason – less air resistance. But physics is a funny thing, fraught with unexpected paradoxes. Consider, for example, the speed capabilities of the helicopter and the car.

The helicopter leaves the ground, when the lift force of the blades begins to exceed its own weight. As soon as these indicators are aligned, the helicopter hangs in the air.

To begin to move forward, the pilot actuates the swash – the movement control rotor. With it, you tilt the helicopter in pitch and roll by creating a difference in lift forces of the rotor blades. Increasing the tilt increases the angle of attack and lift.

However, at some point (with speed around 400 km/h) the helicopter reaches the so-called boundaries separating stream when the amplitude of the oscillation movement of the screw reaches the limit that can lead to failure of the stream with the extremities of the blades.

Unlike the helicopter, the car also lacks aerodynamic problems, but a hard limit on the type of boundary separation of the flow does not exist, it is not surprising that for several years, continued development of a supersonic car Bloodhound SSC, capable of reaching theoretical speed is 1610 km/h.

Source — Popular Mechanics

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