Preamble: We live in a scientific and technological world that is vastly different from the world of a hundred years ago. If someone from that time were to land in our midst today, they would likely find most things around them magical. Each of the technologies surrounding us today had one or a few seminal patents, the potential of which was perhaps seen by few other than the inventors themselves. However, those patents have had an inordinate impact on several technologies that followed. Let us explore each month for the next few months, one or more such patents that changed the world.
Humans have dreamed of flying from time immemorial. This can be seen from the stories of Icarus in Greek mythology. There have also been stories of flying machines, such as Pushpaka Vimana, in Indian mythology, and flying cars (feiche) from Chinese mythology. Various attempts have also been made by others, including gondolas and so on. However, the first powered flight was achieved by the Wright brothers at Kitty Hawk in 1903, which inaugurated the era of heavier-than-air flying machines and, eventually, international commercial flights. However, flying was still relatively slow, noisy, and uncomfortable by today’s standards.
There was an ongoing effort to improve the power-to-weight ratio of aircraft engines, and several improvements and types of engines were tried. One such engine was a rotary aero engine. To understand how this engine works, you can find a clear explanation here. These engines had several advantages, such as Smooth running and good cooling, which gave them a weight advantage. But it suffered from some disadvantages. Rotary engines had to be lubricated like a two-stroke petrol engine in which the lubricant is mixed with the fuel, and some of the lubricant is purged in each exhaust stroke. Power increase also meant size and weight increases. The gyroscopic effect of the rotating engine made the aircraft less manoeuvrable. Further, engine controls were tricky.
In this situation came two closely related engine types – turbine engines and jet engines. They revolutionised aeronautics. The following features are common between them, to put it simply. They work by drawing in air, compressing it, mixing it with fuel, igniting the mixture, and then expelling the high-speed exhaust gases to produce thrust. This process involves several key components, including a turbine, which extracts energy from the expanding gases to drive the engine’s compressor and fan. Such engines may be used for driving a turboprop aircraft or a helicopter.
Most modern helicopters use turbine engines, specifically turboshaft engines. A turboshaft engine is a type of turbine engine specifically designed to produce shaft power. The engine’s job is to drive the main rotor blades, which provide lift and allow the helicopter to hover, take off, and land vertically.
However, jet engines are optimised to expel hot gases at high speeds from the turbines, thereby providing thrust to aircraft. This type of engine was invented by the English RAF officer, Air Commodore Sir Frank Whittle. As would be expected in such developments, there were others working on similar engines. One was Maxime Guillaume who submitted a patent application, but his engine was not feasible. Similarly, Germany’s Hans von Ohain designed a jet engine that was the first to fly. However, Whittle is credited with co-creating the jet engine, which revolutionised air travel. You can see one of the earliest patents of the jet engine here.
Author: JL Anil Kumar
First Published by: Mondaq here