Study of the comfort aircraft norm

In long range aircraft, one reason of discomfort of the passengers are the vibrations and the noise induced by the rotation of the engine. This induces high-level single-frequency excitations (both for noise and vibration). The frequency (located between 25 and 55 Hz) and the amplitude of these excitations vary depending on flight parameters. This study investigates the influence of the frequency and the level of vibration and noise stimuli to discomfort. The aim is to build a global discomfort model. Subjective experiments were carried out in the laboratory, on a test bench allowing to control vibration and noise stimuli. Volunteers separately assessed the vibration, noise and global discomfort. Foot, seat, backrest and armrests accelerations were measured for each participant and each stimulus. As expected, noise or vibration discomfort depends on the excitation level; but no influence of the frequency could be detected. Finally, it appears that specific vibration discomfort strongly influences global discomfort.