What's the aisle width of long range business jet?
Based on this cabin layout of a Gulfstream G500 found on flexjet.com, I measured the aisle width at various places:



The total width is given as 7' 11'' = 241.3cm. The aisle width at the marked positions is then:


63cm (2' 1'')
68cm (2' 3'')
44cm (1' 5'')
51cm (1' 8'')
46cm (1' 6'')
57cm (1' 10'')
50cm (1' 8'')


This would give an average of 54cm (1' 9'') over the measured positions.

Interestingly, the narrowest part (44cm) is less than the FAA minimum for transport category aircraft with more than 10 seats (Is there any limit on how narrow aisles can be?), which would be 20in = 50.8cm.