# Why do airplanes take off into the wind?

Attention: Student Infinite Flight Pilots

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Planes takeoff with windspeed, not ground speed

So when flying into the wind, they can achieve a higher wind speed with less ground speed, effectively using less runway, and vice versa

Edit: Am I a graduate now :3

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One of the primary components of lift is the wind flowing around the wings. The concept of lift can be explained using bernouli’s principle which states that the shape of the wing causes low pressure on top of the wing and higher pressure below the wing which pushes the wing upwards as the airspeed around the wings increases.

A lot of people think that lift is caused by the speed of the aircraft on takeoff roll. This is only partially true. The speed of the aircraft is important indeed, but relative to the wind. This means that even if the wheels were moving at 180 knots but there is no wind around the wings, there is no lift generated. On the other hand, if the plane is moving only at about 130 knots but with a direct 20 knots headwind, your rotate speed is lower in terms of GS.

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Airspeed, it’s what counts.

Taking off into a headwind gives you a higher airspeed and lower ground speed.

Taking off with wind on your tail gives you a lower airspeed and higher ground speed.

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Pilot take up into the wind so they can get lift over the wings. The airspeed of the plane has nothing to do with how a plane takes off into the wind. The wind creates a high and low pressure over the wings and when rotation speed of the aircraft is reached that airplane becomes airborne

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Beat me to it. Was about to post the same

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Co-efficient of lift equation

Cl=1/2 x Air density x Velocity Squared x Surface Area of wing.

Can’t change the air density, can’t change the surface area of the wing therefore you can only change the velocity.

If you do 100 kts with a 20 kt tail wind your ‘actual’ velocity would be 80 kts. = Inefficient

If you do 100 Kts with a 20 kt headwind your ‘actual’ velocity would be 120 kts = efficient.

Never throw away a free bonus! ;)

(obviously simplified!)

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There is a physics person in the house (like me, good job).