-- the issue is bound to spur some awkward encounters . Chart : Compare some of the common airline fees `` It 's a growing problem , no pun intended , '' said George Hobica , president of AirfareWatchdog.com , a site that is part of Smarter Travel Media LLC , which provides airfare deals and advice . `` Everyone suffers . The obese people suffer and the people who are skinny and get spilled over on suffer as well . '' U.S. obesity rates have mushroomed during the last 25 years , but the width of a coach airplane seat has changed little , remaining between 17 and 18 inches in most commercial planes . More than one-third of Americans fall into the obese category , according to the Centers for Disease Control and Prevention . This makes traveling in tight spaces vexing for airlines trying to bolster profits by selling the maximum number of seats . The Federal Aviation Administration does not regulate seat width , but it does require passengers be able to sit belted and with both arm rests down to comply with safety standards . In April , UAL Corp. 's United Airlines formalized a
-LRB- CNN -RRB- -- You pay for checking your baggage , for snacks and for extra legroom . Word is one airline has even toyed with charging you to use the toilet . So it makes perfect sense to some fliers that heavier passengers should pay for spilling over into the next seat . Earlier this year , United Airlines formalized a policy that charges some larger passengers for a second seat . Frequent flier Ross Murphy , 54 , has been sandwiched between larger fliers in coach , and he believes they should have to shell out for a second seat . `` They have a right to sit in the seat next to me , '' said Murphy , who travels cross-country at least 15 times a year to watch his sons ' sporting matches . `` But they do n't have a right to sit in my lap . '' A growing number of airlines are forcing bigger passengers to pay more as they cope with the costly and uncomfortable quandary that arises when obese passengers can not squeeze into a single coach seat . With airlines trimming flight schedules -- meaning fuller passenger loads this summer