Passengers’ seat vibration exposure on turboprop aircraft flights

Abstract

Background

Turboprop aircraft offer the possibility of lower emissions for regional travel in comparison to jets. Future low-carbon aircraft concepts include propeller-generated thrust powered from fuel cells, hydrogen, biofuel, battery or hybrid power. The noise and vibration experienced in a turboprop cabin is different to that experienced in a jet, with signals characterised by tonal components related to the propeller blade pass frequency. These components have been associated with noise and vibration discomfort. There are few published studies of aircraft cabin vibration measured on the seat surface according to ISO2631-1; none report data for the whole flight.

Objective

The objective was to measure and evaluate the vibration experienced by passengers for complete turboprop flights and compare vibration data with standards associated with vibration comfort.

Methods

Vibration data was measured on the surface of three occupied seats during two turboprop aircraft flights. Measurements were made on full flights, and covered the entire duration from gate-to-gate.

Results

Data showed that the vibration is highly tonal, and is affected by position and flight phase. Frequency-weighted vibration showed magnitudes below thresholds for health risk. The highest magnitudes of vibration occurred at the blade pass frequency and its harmonics. These frequencies are rejected by standard comfort assessment methods that use frequency weightings.

Conclusions

Whole-body vibration exposure in the turboprop tested in this study did not approach health risk thresholds using ISO2631-1. Analysis of the vibrational comfort requires use of band-limited vibration assessment methods to include the dominant vibration components in analysis.