One day in 1968, members of the BeeGees were flying aboard a British Airways Vickers Viscount plane, listening closely to the aircraft noise inside the cabin. “It was one of those old four-engine 'prop' jobs’ that seemed to drone the passenger into a sort of hypnotic trance, only with this it was different,” the late singer Robin Gibb once said in a BeeGees anthology. “The droning, after a while, appeared to take the form of a tune, which mysteriously sounded like a church choir.” According to Gibb, it inspired one of the band’s most famous songs, I Started A Joke.

For most passengers though, aircraft noise is more likely to be a pain than a source of inspiration. Despite great advances in aviation, if the engines are whirring, the wind is whizzing and the air conditioning is pumping, it’s still pretty noisy inside passenger jets. Could new technology help? And are there any tricks passengers can use to avoid noise?

The noise during a typical plane journey can vary significantly. Take-off and landing are the loudest moments, when noise levels inside the cabin can reach 105 decibels (dB). At cruising altitudes, noise drops to around 85 dB, says Pamela Mason of the American Speech-Language-Hearing Association (ASHA). Long exposure to 85 dB can cause temporary hearing problems. “Many people notice tinnitus – ringing in the ear – following a long flight, an early symptom of noise damage,” says Mason. And if noise goes higher than 90 dB for eight or more hours per day, it may lead to permanent hearing loss, warns the US Federal Aviation Authority (FAA). On older aircraft, or towards the back of a plane, noise levels can often get close to this threshold.

Aircraft manufacturers and airlines recognise the issue, and try to reduce the noise inside cabins. But it’s far from straightforward, because some noise reduction techniques – such as adding thick insulation to the cabin walls – can add weight, which increases fuel consumption. So what are engineers doing to tackle the problem?

Damping the noise

One of the main sources of noise is wind. So during the design phase of modern aircraft, computational tools model the aerodynamics of the aeroplane to highlight areas of high airflow that are likely to increase cabin noise. This allows engineers to reshape their designs, says Alan Pardoe, director of product marketing at Airbus. Such techniques, he says, helped the double-decker Airbus A380 plane to be recognised by the UK Noise Abatement Society as the quietest jet airliner on the market.