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The Airbus A220 is widely considered to be the quietest commercial aircraft in production today. The Boeing 737 MAX is praised for being 50% quieter than its predecessor, the 737 Next Generation series. However, compared to the smaller Airbus, it doesn’t come close. The A220-300 offers a similar seating capacity to many single-aisle jets but in a much smaller package, which also gives it the advantage of being much quieter.
On takeoff, a 737 MAX averages around 70 decibels, which is roughly 40% quieter than the older 737-800. The A220’s noise footprint is significantly reduced and perceived level, said to be 18 decibels less than the bigger Boeing. While the technical difference is only a few decibels, studies show that the difference is large enough for observers that the Airbus seems far quieter from the ground. According to MDHearingAid.com, that level makes the Boeing three or four times louder.
For context, that’s the difference between standing in the middle of a quiet library or the corner of a busy street with trucks driving by at full speed. Inside the cabin, passengers have also reported a noticeable difference in sound levels on the A220 compared to the 737 and even the Airbus on the A320 single-aisle jetliner family.
Bottom Line: How Two Of The Quietest Jetliners Really Stack Up
The power plants that these two jets use are the source of the sound difference during takeoff. The Pratt and Whitney PW1500G has been measured at 82 decibels and has a characteristic whine due to its unique design, where the front fan spins at a lower speed in the internal turbine. This reduces the roaring sound heard from other turbofan engines because of the lower velocity airflow. Some observers have said that there is an identifiable sound from the A220 described as a unique whale-like or flute noise.
The Boeing 737 MAX is powered by CFM International LEAP-1B engines with unique chevron-shaped engine nacelles measured at 86.6 decibels. The sawtooth trailing edges on the engine housings not only help with fuel efficiency by mixing hot exhaust and cooler bypass air better, but also cut down on turbulent sounds generated during the high thrust phase of takeoff. The aircraft also has engine nozzles and honeycomb liners that further mitigate specific sound frequencies to reduce the overall noise level.
While the overall volume is lower than the legacy 737, the MAX still exhibits the buzz saw tone typical of modern high-bypass turbofans at high power. This is caused by the tips of the large fan blades spinning at supersonic speeds during the initial climb.
Unlike some Airbus models that produce a high-pitched blue note or whistle, the 737 MAX is often described as having a deeper, more muffled engine note due to its chevron design. While there is a perceptible difference, Air Insight notes that it would be difficult to pick out the individual planes by sound from a busy airport operating at the same time.
Behind The Numbers: Measured Versus Perceived Noise On The Tarmac
The takeoff stage of flying is where the differences in noise from different aircraft are most pronounced due to the extreme thrust required. In modern high-bypass engines, the large front fan blades spin so fast that their tips exceed the speed of sound. This creates a series of small sonic booms, resulting in the characteristic grinding or buzzsaw sound often heard inside the cabin and on the ground. To complicate matters, the human ear doesn’t hear sound on a simple linear scale.
The perceived volume difference is often exaggerated because of how our brains process specific sound frequencies. Takeoff noise is the violent mixing of high-speed, hot exhaust gases with the cooler, stationary ambient air. This creates intense turbulence and pressure waves that we hear as a deep roar.
In general, our sense of sound is highly sensitive to frequency changes, and the instrument-measured volume is heard differently in many cases. Three decibels is considered to be the smallest difference that a human ear can detect between two distinct sound sources. Humans are most sensitive to mid- to high-frequency sounds, which range from 2,000 to 4,000 Hertz.
A 10-decibel increase actually represents a tenfold increase in physical sound energy, but our brains only perceive it as a doubling of loudness. When overall decibel levels are comparable, aircraft with sound characterized by high-pitched whines or buzzsaw noise are considered much louder and more disruptive than those with a low-frequency rumble.
The Risks Of Innovation: The Stumbling Blocks Hitting The A220
High-altitude engine shutdowns were reported shortly after the A220 entered commercial service, frustrating operators of the newest and smallest Airbus. Internal vibrations caused parts to fail at high power levels and specific altitudes, according to the investigators. This resulted in strict software limits on engine power above 29,000 feet (8,839 m) feet until a hardware fix was implemented. Unfortunately, this was just the tip of the iceberg for the innovative new Airbus.
There has been only one major issue with the Airbus A220 since it began commercial service, but that problem has proven to be a significant dilemma for many operators. The highly advanced and efficient P&W GTF turbofans have, unfortunately, become a handicap due to manufacturing flaws that were discovered in 2023. Since then, the worldwide fleet of jetliners that rely on these power plants has been plagued by maintenance groundings due to massive recalls over potentially catastrophic defects.
Pratt discovered that metal used in the manufacturing of turbine discs could contain impurities that make these crucial components prone to sudden failure much sooner than their anticipated service lives should last. The primary driver for the abundance of caution is the fact that, in a worst-case scenario, the entire engine could be devastated in an uncontained failure by the sudden breakdown of one of these discs. Should that happen in flight or during a takeoff roll, the results could be tragic.
Persistent Pratt & Whitney GTF Engine Complications Prompt Air Austral To Retire Airbus A220-300 Fleet
The airline reportedly plans to operate the A220 only until the summer of 2026.
A220 Flyers Feel The Heat At Sandy Airfields
Operators that typically fly to hot and sandy climates, like Air Baltic or Egypt Air, have also had some unique difficulties with the new A220. The carriers flying to and from these uniquely challenging airfields have found that the engine combustors were experiencing significantly faster wear and tear than originally predicted.
The large-scale problem with the GTF series engines, which are the exclusive power plants of the A220, was also preceded by some high-altitude in-flight shutdowns. The combined impact of these mechanical issues has also left aircraft grounded for extended periods while waiting for spare parts. The global recall has left few surplus parts and power plants available, making any major maintenance issue with a P&W GTF a potentially grounding event that could leave aircraft out of service for very extended periods.
Milestone 220: Airbus Celebrates 500 Deliveries Of Its “Game-Changing” A220
Airbus has reached 500 A220 deliveries, but challenges still loom.
How Pratt Is Teaming Up With Airbus To Fix The Fleet
The P&W GTF engine series is a core pillar of the clean sheet that has made the aircraft capable of the efficiency, performance, and capacity that customers enjoy. In conventional engines, the fan and turbine are on a shaft and must spin at the same speed. In a GTF engine, the gearbox allows the large front fan to spin slower for maximum air-moving efficiency while the internal turbine spins faster for optimal power generation.
This decoupling gives the GTF an exceptionally high 12:1 bypass ratio, one of the highest in the world, which allows the engine to move a huge mass of air at a lower velocity. That not only improves fuel efficiency, sound levels, and emissions, but also gives the aircraft a much longer range than older regional jets. In order to overcome the technical issues that are holding back the jet, Airbus and Pratt are working closely together.
Airbus and Pratt & Whitney have introduced a series of block upgrades to move the A220 past these early reliability issues. The advantage standard comes on new A220s being delivered now and includes upgraded engine components to improve airflow and cooling. These enhancements are designed to improve time on wing between major maintenance periods by 10 to 15%.
The enhanced cooling design is a new high-pressure turbine blade system that uses advanced coating and cooling hole patterns to prevent the heat-related cracking seen in first-generation iterations. The latest flight control and engine computer software have optimized how the engine handles thrust transitions, virtually eliminating the resonance issues that caused the earlier power restrictions.
Here’s How Much Quieter The Airbus A350 Is Compared To The Boeing 787
The battle between two aviation giants heats up as they strive for the quietest cabin experience.
The Silent Generation: The Other Quiet Jets On The Ramp
Some reports have put the Embraer E195-E2 down as the quietest commercial aircraft, surpassing the A220. However, all three of these aircraft, and the Airbus A320neo family, are grouped as the new and most silent generation in commercial airplanes. The Embraer jet has been described as having a very similar engine noise to the A220. Likewise, the A320neo is considered relatively on par with the 737 MAX.
Just like the 737 MAX, the latest and greatest version of the Airbus A320 single-aisle claims a 50% quieter takeoff than its A320CEO predecessors. The Airbus is unique among the other jets in this group for the option between two power plants. The customer can choose a P&W GTF or a CFM LEAP engine model. This puts the aircraft in a good market position to attract buyers, but ultimately, either turbofan they choose has a similar sound level.
The Embraer, like the 737 MAX and A220, has just one powerplant option. It is powered only by P&W GTF engines, very similar to the A220. In a standout difference, the E195-E2 achieved a 75% better noise level over the preceding model because the legacy E195 used General Electric CF34-10E engines. The switch to P&W helped achieve not only a significantly quieter takeoff but also cut fuel consumption by 25% and reduced emissions by half.
