95b323b7_of_Size__Policies___Yahoo_News__Stated_policy
[Airline] US Airways [Costs] If the passenger will not change flights, they will be required to purchase a second seat at the gate. N/A [Stated policy] 
Takes it case-by-case, offering extra space when available may require waiting for a later flight.
Airline "Customer of Size" Policies - Yahoo News
Stated policy