Design and analysis of comparative experiments to assess the (dis-)comfort of aircraft seating

This paper focuses on the comparative assessment of comfort and discomfort (hereafter, (dis-)comfort) for air- craft seating. Subjective and objective data of seating (dis-)comfort were collected during an experiment in- volving 20 volunteers who tested 3 aircraft double-seats in upright and reclined position. In order to minimize experimental uncertainty due to well-known noise factors (i.e. patterns of discomfort during the work week and during the work day, order of evaluation, inter-individual differences), experimental trials were performed according to a crossover design. Statistical data analysis aimed mainly at investigating (dis-)comfort differences across seat conditions; gender-based differences in perceived discomfort on different body parts; effect of sitting duration on perceived discomfort on different body parts. The experimental results show that differences across seat conditions impacted differently on perceived discomfort depending on gender, body parts and sitting duration. No significant differences in perceived discomfort across gender were evident for the lightweight seat in both upright and reclined positions. On the contrary, for both baseline configurations, perceived discomfort at head and neck areas was higher for males than for females. For all seat conditions, participants experienced a significant worsening of perceived comfort over time at shoulders, back, sacrum and thighs and, in addition, at upper body area (i.e. neck, arm and forearm) and knees only for seats in reclined position.