I've noticed that cabin configuration, most notably 3-4-3 on 777s, and pax obesity routinely come up in the civil aviation forums. Sure, I understand that economy class seating and aisles will never be as comfortable or as wide as what is featured in first and business class. Nevertheless, as airlines try to cram in more pax and pax keep getting bigger, will this affect emergencies at all?
Case in point, if there's a passenger of size who can barely(or can't) comfortably get down the aisle of a 3-4-3 777, what happens when he/she gets stuck during an evacuation? In the aisle, what if the rear exits cannot be used? I can also easily imagine a case where an obese pax is in the middle or aisle seat, gets stuck, and blocks the pax in that seating section from getting out. I fear that inevitably there will be a fatal incident where narrow aisles combined with overly large pax will be blamed for fatalities in what should have been a standard evacuation.
I'm fairly certain that the FAA instituted a minimum aisle width in the 1980s following an accident, but should these rules be revisited given that pax, particularly in the US, are getting increasingly large?