Timelines · Engine innovations
A century and a half in six moves: fire tamed into strokes, the spark deleted, the strokes replaced by flow, the exhaust taxed, the engine hybridised — and finally deleted. Every entry links to the page where its physics runs live.
Nicolaus Otto tames combustion into a repeatable cycle: draw in, squeeze, burn, exhaust. Compressing the mixture before lighting it is the masterstroke — it turns a curiosity into a machine efficient enough to matter. Every petrol engine since is a footnote to this cycle.
Rudolf Diesel squeezes air so hard it ignites the fuel by heat alone. Higher compression means more work wrung from every degree of heat — the most efficient combustion engine ever built, and still the engine of everything heavy: trucks, trains, ships, generators.
Frank Whittle and Hans von Ohain, independently and in a hurry, replace strokes with flow: compress continuously, burn continuously, let a turbine pay the compressor and the exhaust push the aircraft. Within twenty years the piston airliner is extinct above the weather.
A third of the fuel’s energy leaves down the exhaust pipe — so bolt a turbine in the flow and use it to cram more air in. Turbocharging resurrects lost energy as boost, and Formula 1’s 1,400-horsepower qualifying monsters prove the point extravagantly before road cars make it ordinary.
The Toyota Prius pairs a petrol engine with two motor-generators through one planetary gear, letting a computer choose the mix every millisecond. The engine finally escapes its worst habitat — stop-and-go traffic — by handing those minutes to electricity.
Lithium batteries finally hold enough energy to matter, and the electric motor — older than Otto’s engine — gets its century. Full twist from zero speed, one moving part, no gearbox worth the name: the drivetrain this whole site explains, reduced to almost nothing. What remains is the physics of the field.