Aircraft Engines 101: The advantages of the turbofan engine compared to the turbojet for jet charters
When compared to today’s standards, it’s hard to believe that private jets and commercial aircraft were once powered by the noisy and gas-guzzling turbojets of old. We have certainly come a long way from the turbojet engines of the World War II era with highly-efficient and quiet turbofan-driven aircraft. It’s important to understand the basic principles of both engines to appreciate the value of the turbofan-driven private aircraft for private jet charters.
Stratos Jet Charters has spent time researching aircraft engines and their advantages for private jet charters. What we’ve learned thus far is that every private jet engine operates differently but that they mostly operate by forcing air into a tube where it is compressed, mixed with fuel, burned and exhausted at a high speed to generate thrust. This concept applies to both turbojet and turbofan jet engines.
In the late 1930s, the turbojet engine, the oldest general purpose jet engine, was developed independently by Frank Whittle from the United Kingdom and Hans von Ohain of Germany. There is some debate among historians as to who invented the engine first, but most credit Whittle with the original design and von Ohaim with the engine’s first successful flight.
The turbojet engine operates by compressing air into a chamber, heating it and allowing it to expand through the turbine into a nozzle where it is accelerated to high speed. This operational concept is relatively simple and was used on a number of aircraft during World War II. However, the simplicity and high exhaust speed of the turbojet make it an exceptionally noisy and inefficient engine for private jet charters.
The turbofan engine, on the other hand, is an ideal engine due to its high thrust and fuel efficiency capabilities. Turbofans operate almost the same way as the turbojet engine, only with the addition of a fan component. Air enters the turbofan engine through the inlet and is passed along through the fan while the rest of it is sent to the burner where it is mixed with fuel and ignited to generate propulsion. Unlike their turbojet predecessors, turbofans derive their thrust from two sources: the engine core and the fan.
As such, turbofans have a much lower net exhaust than turbojets and are a far more efficient engine at subsonic speeds than turbojets. Since most charter flights operate at subsonic speeds, the turbofan is a much more practical engine choice for charter aircraft. In a turbofan-driven aircraft, charter pilots can throttle back to cruise and save hundreds of dollars in gas bills during their flight. For these reasons, the turbofan is the engine of choice for private jet charters and commercial airlines.