engineering

Parafoil

Parafoil is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Parafoil rather than just read about it. In short: A parafoil is a nonrigid (textile) airfoil with an aerodynamic cell structure which is inflated by the wind. Ram-air inflation (created by dynamic air pressure from the parachute's motion through the air) forces the parafoil into a classic wing cross-section.

Key takeaways

Parafoil belongs to engineering; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Parafoil to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Parafoil from memory before moving on to harder problems.

Reference excerpt

A parafoil is a nonrigid (textile) airfoil with an aerodynamic cell structure which is inflated by the wind. Ram-air inflation (created by dynamic air pressure from the parachute's motion through the air) forces the parafoil into a classic wing cross-section. Parafoils are most commonly constructed out of ripstop nylon. The device was developed in 1964 by Domina Jalbert (1904–1991). Jalbert had a history of designing kites and was involved in the development of hybrid balloon-kite aerial platforms for carrying scientific instruments. He envisioned the parafoil would be used to suspend an aerial platform or for the recovery of space equipment. A patent was granted in 1966. Deployment shock prevented the parafoil's immediate acceptance as a parachute. It was not until the addition of a drag canopy on the riser lines (known as a "slider") which slowed their spread that the parafoil became a suitable parachute. Compared to a simple round canopy, a parafoil parachute has greater steerability, will glide further and allows greater control of the rate of descent; the parachute format is mechanically a glider of the free-flight kite type and such aspects spawned paraglider use. The air flow into the parafoil is coming more from below than the flight path might suggest, so the frontmost ropes tow against the airflow. When gliding, the angle of attack is lowered and the airflow meets the parafoil head on. This makes it difficult to achieve an optimum gliding angle without the parafoil deflating. In 2019 Jalbert was awarded posthumously the Fédération Aéronautique Internationale (FAI) Gold Parachuting Medal for inventing the parafoil. Parafoils see wide use in a variety of windsports such as kite flying, powered parachutes, paragliding, kitesurfing, speed flying, wingsuit flying and skydiving. The world's largest kite is a parafoil-variant.

Patents U.S. patent 3,285,546 Multi-cell wing type aerial device, filed October 1964, issued November 1966

Illustrations

Worked examples

Example 1 — a first encounter with Parafoil

Start with the simplest possible case. Write down what Parafoil claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Parafoil before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Parafoil ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Parafoil

In research: Parafoil appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Parafoil in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Parafoil is common in secondary-school and first-year university syllabi. It links to neighbouring topics Aerospace engineering, Aircraft wing design, Kites, so understanding it makes those chapters shorter.
In everyday life: Look for Parafoil outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Parafoil in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Parafoil means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Parafoil out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Parafoil in simple terms?

Why does Parafoil matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Parafoil?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Parafoil.