# How the Rogallo Flexible Wing Kite Works

> A 1948 patent for a kite with a flexible, non-rigid wing that uses air pressure to maintain its shape during flight.

- **Patent:** US 2546078
- **Original title:** Flexible kite
- **Owner:** Individual
- **Granted:** 1951
- **Status:** Public domain (expired)
- **Times cited:** 23
- **Field:** aerospace, mechanical

## What it does

The patent describes a kite wing made of flexible material that lacks a rigid frame. Instead of using wooden struts to hold its shape, the wing relies on the pressure of the wind to inflate and maintain an airfoil shape while tethered. This design allows the kite to be lightweight, foldable, and capable of stable flight without heavy structural supports.

## What it does NOT cover

- Does not cover rigid-frame kites like traditional box or diamond designs.
- Does not cover motorized aircraft or powered flight vehicles.
- Does not cover wings made of rigid materials like metal or wood panels.

## The clever bit

The inventors realized that a wing does not need a solid skeleton if the air pressure itself can act as the structural support, drastically reducing weight and complexity.

## Real-world examples

1. Modern hang gliders
2. Paragliders
3. Stunt kites
4. Parafoil parachutes

## Why it matters

This design became the foundation for modern hang gliders and paragliders. By proving that a flexible, fabric-based wing could provide stable lift, the Rogallos enabled the development of recreational foot-launched aviation.

## Frequently asked questions

### What does How the Rogallo Flexible Wing Kite Works cover?

A 1948 patent for a kite with a flexible, non-rigid wing that uses air pressure to maintain its shape during flight.

### Who owns patent US 2546078?

Individual owns this patent, granted in 1951.

### When does this patent expire?

This patent has expired and is now in the public domain — anyone can use the invention freely.

### What is patent US 2546078 cited by?

This patent has been cited by 23 later patents that build on its ideas.

### What problem does this patent solve?

This design became the foundation for modern hang gliders and paragliders. By proving that a flexible, fabric-based wing could provide stable lift, the Rogallos enabled the development of recreational foot-launched aviation.

### What does this patent NOT cover?

Does not cover rigid-frame kites like traditional box or diamond designs.

**Full plain-English explainer:** https://patentbrief.org/patent/us/2546078/rogallo-wing-hang-glider

**Original patent:** https://patents.google.com/patent/US2546078

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._


## Related patents

Semantically similar inventions in the PatentBrief corpus:

- [How the Modern Frisbee Design Works](https://patentbrief.org/patent/us/3359678/frisbee-flying-disc) — A 1967 patent describing the specific aerodynamic shape and raised ribs that allow a plastic disc to fly straight and steady.
- [How the Wright Brothers Invented Modern Airplane Control](https://patentbrief.org/patent/us/821393/wright-brothers-flying-machine) — The foundational patent for the first successful powered, heavier-than-air flying machine that could be controlled in flight.
- [How Floyd Smith Designed the Modern Parachute Pack and Harness](https://patentbrief.org/patent/us/1462456/free-fall-parachute-smith-irvin) — A 1923 patent for a parachute system that introduced a reliable pack and harness design for aviators to safely exit aircraft.
- [How the Wiffle Ball Design Works](https://patentbrief.org/patent/us/2776139/wiffle-ball-mullany) — A 1954 patent for a lightweight, perforated plastic ball designed to curve easily when thrown, famously known as the Wiffle ball.
- [How the Hula Hoop Works](https://patentbrief.org/patent/us/3079728/hula-hoop-wham-o) — A 1963 patent for a lightweight, rigid plastic hoop designed to rotate around a human waist through rhythmic body movements.