When is damage to the eardrum most likely to occur during flight?

Damage to the eardrum is most likely to occur during descent because this phase of flight involves rapid changes in atmospheric pressure. As an aircraft descends, the air pressure outside the aircraft increases while the pressure inside the middle ear may not equalize as quickly. If the Eustachian tubes, which connect the middle ear to the throat and help regulate ear pressure, cannot open adequately to equalize the pressure, it can lead to a condition known as barotrauma. This pressure imbalance can result in pain or damage to the eardrum. During ascent, while pressure changes do occur, they generally happen at a more manageable rate and are often more easily compensated for by the body, making descent the critical phase for potential eardrum damage.