# Frank Whittle's Early Jet Engine Design

> Frank Whittle's 1937 patent for an aircraft propulsion system using a gas turbine, which laid the foundation for modern jet engines.

- **Patent:** US 2168726
- **Original title:** Propulsion of aircraft and gas turbines
- **Owner:** Individual
- **Granted:** 1939
- **Status:** Public domain (expired)
- **Times cited:** 50
- **Field:** aerospace, mechanical

## What it does

The patent describes a propulsion system for aircraft that utilizes a gas turbine to generate thrust. It details a compressor that draws in air, a combustion chamber where fuel is burned to increase the energy of the air, and a turbine that extracts energy from the hot exhaust gases to drive the compressor. The high-velocity exhaust is then expelled through a nozzle to create forward propulsion. This design effectively replaces the traditional piston-and-propeller engine with a continuous flow process.

## What it does NOT cover

- Does not cover turbofan engine designs with high bypass ratios common in modern airliners.
- Does not cover specific electronic fuel injection or digital engine control systems.
- Does not cover ramjet or scramjet propulsion systems that lack rotating compressor components.
- Does not cover modern materials like single-crystal turbine blades or ceramic matrix composites.

## The clever bit

Whittle realized that by using a turbine to drive the compressor, he could create a self-sustaining cycle that produced significantly more thrust than the power required to keep the engine running.

## Real-world examples

1. Gloster E.28/39
2. Early Whittle W.1 turbojet engines
3. Foundational design for all modern turbojet engines

## Why it matters

This patent represents the birth of the jet age. It provided the technical blueprint that allowed the UK and later the US to transition from propeller-driven aircraft to high-speed jet flight, fundamentally changing military and commercial aviation forever.

## Frequently asked questions

### What does Frank Whittle's Early Jet Engine Design cover?

Frank Whittle's 1937 patent for an aircraft propulsion system using a gas turbine, which laid the foundation for modern jet engines.

### Who owns patent US 2168726?

Individual owns this patent, granted in 1939.

### 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 2168726 cited by?

This patent has been cited by 50 later patents that build on its ideas.

### What problem does this patent solve?

This patent represents the birth of the jet age. It provided the technical blueprint that allowed the UK and later the US to transition from propeller-driven aircraft to high-speed jet flight, fundamentally changing military and commercial aviation forever.

### What does this patent NOT cover?

Does not cover turbofan engine designs with high bypass ratios common in modern airliners.

**Full plain-English explainer:** https://patentbrief.org/patent/us/2168726/jet-engine-whittle

**Original patent:** https://patents.google.com/patent/US2168726

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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:

- [Robert Goddard's Early Design for Liquid-Fueled Rocket Engines](https://patentbrief.org/patent/us/1102653/liquid-fuel-rocket-goddard) — A foundational 1914 patent by Robert Goddard detailing the basic mechanical structure of a rocket engine using liquid fuel.
- [Igor Sikorsky's Early Design for a Vertical Takeoff Aircraft](https://patentbrief.org/patent/us/1994488/helicopter-sikorsky) — A 1935 patent by aviation pioneer Igor Sikorsky detailing a mechanical configuration for an aircraft capable of direct vertical lift.
- [How Ole Evinrude Invented the Modern Portable Outboard Motor](https://patentbrief.org/patent/us/1001260/outboard-motor-evinrude) — A 1911 patent for a compact, detachable marine engine that allowed small boats to be powered by a portable, gasoline-driven propeller unit.
- [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.
- [John Holland's Design for an Early Submarine Boat](https://patentbrief.org/patent/us/815350/holland-submarine) — This 1906 patent by John P. Holland describes an early design for a submarine, a vessel capable of traveling underwater, laying the groundwork for modern naval technology.