If you’ve flown on board an Airbus A321neo or an A320neo, you’ve probably heard a horn-like sound before the engines spool up. More so, you can hear them well from the ground and even from far away. That horn-like sound you hear is a result of the new engine design of the Airbus NEO jets, particularly the A321neo, A320neo, and A330neo. These engines are called GTF or geared turbofan engines.
So before I talk about why this horn-life sound from Airbus NEO jets come out, allow me firs to share what a GTF or geared turbo fan engine is.
How a geared turbofan engine works
A geared turbofan engine is a kind of turbofan aircraft engine in which the fan rotates at a slower speed than the low-pressure compressor and turbine due to the employment of a gear system. The gear system decreases the amount of stress on engine components, improves fuel economy, and reduces engine noise.
The fan, which produces the majority of the thrust, draws air into the engine. The low-pressure and high-pressure compressors compress the air before it is combined with fuel and burnt in the combustion chamber. The hot combustion gases power the high-pressure turbine, which in turn powers the low-pressure compressor, completing the cycle.
The geared turbofan engine is a popular option for modern passenger aircraft due to its combination of high thrust, low noise, and better fuel economy.
Planes that use GTF
Several versions of current commercial aircraft engines employ geared turbofan (GTF) engine technology, and not only the Airbus NEO (New Engine Option) planes. Here are some of the most often utilized GTF engines:
- Pratt & Whitney PW1100G-JM – Used on Airbus A320neo family aircraft.
- CFM International LEAP-1A – Used on Airbus A320neo and Boeing 737 MAX family aircraft.
- Rolls-Royce Trent 7000 – Used on Airbus A330neo aircraft.
- Pratt & Whitney PW1500G – Used on Embraer E2 family aircraft.
These are some of the most popular GTF engines on the market today, however there are additional kinds and brands available. GTF technology is constantly evolving, and new engines are being developed to satisfy the demands of the aerospace industry.
Just how efficient are the GTF engines?
GTF engines use less fuel and emit less pollutants than traditional turbofan engines. This is because of a number of things, such as:
- Slow-turning fan: The gear arrangement enables the fan to rotate at a slower rate than the low-pressure compressor and turbine, lowering engine component stress and boosting fuel economy.
- Aerodynamic enhancement: The GTF engines’ design is intended for better aerodynamics, which further boosts fuel economy.
- Less noise: Compared to traditional turbofan engines, GTF engines emit less noise due to their superior aerodynamics and slower fan speed.
Generally speaking, GTF engines may reduce fuel consumption and CO2 emissions by up to 15% when compared to traditional turbofan engines. A number of variables, such as the particular engine type, the size of the aircraft, and the operating circumstances, will affect the precise amount of fuel savings.
So what is that horn-like sound we hear from an Airbus NEO plane?
Airbus NEO planes may make a horn-like sound just before takeoff because the GTF is built differently than traditional turbofan engines. It is a result of the high-pressure compressor in the engine, which is particularly noticeable on aircraft powered by GTF engines, such the Airbus NEO jets. Before it is burnt with fuel in the combustion chamber, the air that the engine draws in must first be compressed by the high-pressure compressor. The sound that results from this compression process is distinctive and is frequently referred to as “spool up.” This explains why the horn-like sound made by GTF engines after takeoff.
It is important to note that the sound is normal and that the engine is functioning according to plan. The horn-like spool up sound on an Airbus NEO plane is a sign that the engine is producing the necessary power to propel the aircraft forward and generate lift, which is essential for takeoff
First love never dies. I fell in love with airplanes and aviation when I was a kid. My dream was to become a pilot, but destiny led me to another path: to be an aviation digital media content creator and a small business owner. My passion for aviation inspires me to bring you quality content through my website and social accounts. Aviation is indeed in my blood and blog!
