• Pixel-art sticker of Liftor, personifying Lift Equation, with the caption “Faster Air, More Lift.”

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Liftor

Lift Equation Physics

\[L = \tfrac{1}{2}\rho v^2 C_L A\]
$4.99 USD
$4.99 USD
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Meet Liftor, a wing who rises more the faster the air rushes past him. Lift grows with air density, wing area, lift coefficient and the square of speed. A small plane with 16 m² of wing at 50 m/s makes about 12 000 N, enough to hold up roughly 1250 kg. Pixel-art kiss-cut sticker in 2, 3, 4 and 6 inches; equation, symbols and sources in the physics panel below.

Size
Surface

Flat $6 shipping worldwideMade to order, ships in 2–5 business days

Details

Size3″ × 3″

3″ × 3″ kiss-cut sticker.

Shipping

Flat $6 shipping on every order, worldwide, whatever's in it.

Delivery times & where we ship

Returns & replacements21 days

Every item is printed to order, so we can’t accept returns or exchanges for change of mind, or if you ordered the wrong size or colour.

Print defect, misprint, damage or the wrong item? We’ll send a free replacement, or a refund if you prefer. Report it within 21 days of delivery with a photo; no need to send it back.

Full refund & replacement policy

The physics

Meet Liftor, a wing who rises more the faster the air rushes past him.

A wing is shaped and tilted so that it turns the passing air downward. Pushing air down means the air pushes the wing up. The air flowing over the curved top also ends up at lower pressure than the air underneath, and that pressure difference adds up to the lifting force.

Engineers sum it all up in the lift equation, L = ½ρv²C_LA. For a small plane with 16 m² of wing, a lift coefficient of 0.5, flying at 50 m/s through sea-level air with density 1.225 kg/m³, the lift is about 12 000 N. That is enough to hold up roughly 1250 kg.

Because lift grows with the square of speed, a plane flying twice as fast gets four times the lift. A plane in thin high-altitude air must fly faster to get the same lift.

Wing flaps and slats raise the lift coefficient, which is why airliners extend them for slow take-offs and landings.

Equations

\[L = \tfrac{1}{2}\rho v^2 C_L A\]
SymbolMeaningUnit
\(L\) lift force \(\mathrm{N}\)
\(\rho\) density of the air \(\mathrm{kg/m³}\)
\(v\) speed of the air past the wing \(\mathrm{m/s}\)
\(C_L\) lift coefficient \(\mathrm{dimensionless}\)
\(A\) wing area \(\mathrm{m²}\)

Sources

  1. NASA — The Lift Equation
  2. Wikipedia — Lift coefficient

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