from: Aviation Today – May 23, 2006

http://www.aviationtoday.com/reports/crampedseat.htm

Cramped Seating Can 'Trap' and 'Trip' Passengers During Emergency Evacuation'

More space needed for today's overweight, aging passengers, study concludes

The combination of larger passengers crammed into tightly packed seats could delay emergency evacuation and contribute to potentially fatal embolisms on long flights. Providing more space between seats, and redesigning them to better accommodate persons of widely varying sizes, could have enormous cost implications to the airlines.

A recent study concludes that economy-class passengers are so tightly packed together that they cannot assume a correct "brace" position for emergency landing, and the seats themselves can be obstacles to quick emergency evacuation of the cabin. The current minimum spacing and design standards for transport-category aircraft allow for too-tight seating, and new standards are needed regarding minimum seat width and a minimum area for feet.
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In fact, the study's recommendations are not intended to improve the passengers' comfort. Rather, they are intended to ameliorate the problem of deep vein thrombosis (DVT) on long flights and, more particularly, to expedite emergency evacuation.