Evaluation of shoulder overload during acrobatic flight: Analysis of pilot’s self-report and surface electromyography (SEMG).

Abstract

The physical injuries caused by +Gz include skeletal-muscle overloads. This study has aimed at demonstrating ergonomic conditions of the pilots from the Brazilian Air Force’s Aerial Demonstration Squadron (BAFADS) during flight. All the 13 pilots from the BAFADS were evaluated through an interview. Surface electromyography (SEMG) was employed during the flight manoeuvre simulation (under normal and overload conditions). The report analyses showed perception of discomfort in the right shoulder related to +Gz. The SEMG showed moderate levels of shoulder muscles activation for normal contractions (± 25%). During vigorous contraction, levels of recruitment were high: upper trapezius fibres (± 105%), middle trapezius fibres (± 90%) and posterior deltoid fibres (± 95%). The great demand from the deltoid muscles (posterior fibres) infers a very high level of recruitment from the rotator cuff muscle, which may explain the discomfort in the pilots’ shoulder during the flight manoeuvre. The mutual analysis of both methods not only does it demonstrate a correlation between symptoms and muscle recruitment, but also provides data to implement intervention measures for pilots’ physical training in order to minimise the discomfort symptoms during flights.