Pilot: Hearingloss – will it happen to me?

As a rule, it can be accepted that nearly 12% of the population in developed countries has hearing loss. What is surprising and disturbing is that permanent hearing loss occurs in about 30% of aviators!

This is serious enough to cause organizations like NASA to embark on studies that examine the prevention of hearing loss among pilots. The flight safety foundation in the USA is currently investigating the possibility of aviation accidents due to hearing loss.

Research indicates that pilots generally have to function in a noisy environment and are therefore prone to hearing loss caused by the loud noise.

To place this into perspective, consider the following noise levels (measured in dB level):

  • a whisper – 30dB
  • normal conversation – 55dB
  • busy traffic – 70dB
  • jackhammer – 130dB

Keep in mind that permanent hearing loss can occur from sounds louder than 85dB.

The question is: what is the everyday sound environment in which pilots have to operate?

Studies found the following answers: Inside the cockpit of a Cessna 182 maximum loudness levels of between 105 and 109dB were identified. Noise levels in a Cessna 172S were just over 101dB. In bigger aircrafts like the Airbus A321, softer noise levels of 85dB were measured.

Most of the noise inside and around aircraft is generated by: noise from the exhaust stacks, from propellers as well as airflow from these propellers pushing against the fuselage, and especially from the vibration of air-cooled engines. Finally, noise from other aircraft on the apron is an additional major source of excessively loud sounds.

It is clear, that working in and around an aircraft, poses a great risk for developing a permanent hearing loss.

Furthermore, even if an aircraft with a very quiet interior is operated, hazardous-noise situations still exist. Two examples are the pre-flighting of an aircraft on the tarmac and sitting in the aircraft with the cabin door open. The main source of excessive noise in these situations is the Auxiliary Power Units (APU). This is even more dangerous because pilots often do not use hearing protection or headsets in these situations. Flight Instructors are especially susceptible to noise damage in all of the above situations!

So – how can pilots protect their hearing?

The first step is using the correct headset that will reduce the harmful sounds generated by the specific aircraft. ANR (active noise reduction) headsets are recommended because they improve the signal-to-noise ratio.

The second step is to ensure that pilots have professional hearing assessments regularly.

FINALLY: Hearing is an essential ability for the pilot.

Hearing loss caused by neglect, inadequate headsets or infrequent use of headsets CAN BE PREVENTED.

Compiled by: Dr. René Hugo – Audiologist