For many people, it is the second biggest fear of flying: sitting next to a screaming, kicking, uncontrollable child.Particularly if that child isn't theirs.Next to landing hastily on something other than a runway, sharing the cabin with a fussy toddler is about the worst luck many travelers can imagine. And as the economy and security regulations conspire to squeeze the comforts out of air travel -- lines are long, flights are full and increasingly devoid of amenities -- the sound of a baby's wail can be the breaking point for already frayed nerves.Now, travelers without children are doing some fussing of their own. Some are calling for airlines to implement child-free flights, or designate "family-only" sections on planes, in the wake of some high-profile tantrums.In July, Qantas settled a lawsuit from a woman who claimed that she suffered hearing loss after sitting next to a screaming 3-year-old boy on a 2009 flight from New York to Australia. (Terms of the settlement were not disclosed.) In January, AirTran removed an entire family from a flight before takeoff from Fort Myers, Fla., because their 3-year-old girl was hitting the parents, making noise and refusing to take her seat. And in March, a 42-year-old woman allegedly grabbed a boy (3 years old, again) for kicking her chair during a Southwest flight to Las Vegas.While few travelers would advocate outright assault, a survey of 2,000 travelers released by Skyscanner, a fare-comparison site, in August found that 59 percent of passengers support creating special sections on flights for families. Nearly 20 percent said they would like to see airlines offer child-free flights.The survey brought widespread attention to such ideas, which had long been simmering on message boards, blogs and other bastions of complaint."I would gladly pay extra for a child-free flight," said Ian Burford, a frequent flier from Boston who recently started a Facebook group called Airlines Should Have Kid-Free Flights. "Or at least if they made it easier when booking a flight to say 'I don't want to be seated next to a 1-year-old.' That would be helpful."Mr. Burford said he started his group (two members and counting) after suffering through a flight from Los Angeles to England seated behind a screaming child."The parents were not doing a thing to stop it," he said. "They were just sort of weakly smiling and giggling like, 'Oh, what can you do?' But give them a pacifier, do something to make them stop."It would be easy to dismiss the demands for separating children on flights if they were coming only from the childless. But many parents support the idea as well.A family-only section would give children and parents the freedom to "chat, watch Nickelodeon and laugh out loud," read a recent post on Madame Noire, a blog catering to African-American women. "And yes, the kids can cry if they want to."After all, "do childless passengers really think it's all gravy when parents can't calm down their screaming child?" the post continued. "It's just as stressful for the parent as it is for the child and the other passengers, but it's a fact: kids cry."The idea even has some precedence in Congress: In 2007, Rep. Heath Shuler, a Democratic congressman from North Carolina, introduced legislation that would force airlines to create a family-only section on planes. His motivation, however, was protecting young eyes from the sometimes-violent films shown on commercial flights. (The bill gained some media attention, but has yet to come to the floor for a vote.)But all the crying in the world -- from children or adults -- isn't likely to persuade the airlines to offer child-free flights, said David Castelveter, spokesman for the Air Transport Association, a trade group representing America's largest airlines."This is an industry that's working very hard to return to profitability," he said. "No way is any airline going to discourage someone from taking one flight over another. I just can't see that happening."Even if the airlines were awash in profits, the logistics of operating a large airline would still make the idea difficult to implement, he said. "There are many markets in this country where airlines offer one, maybe two flights a day," Mr. Castelveter said. "You're now going to limit people from flying one of those times? As a parent, I would be pretty annoyed if I were forced to take an 8 a.m. flight instead of one at noon."Family-only sections would present their own set of headaches, he said, and are just as unlikely to become reality. "What about the person who says, 'I want to sit up front, but my son wants to sit with the family?' " he said. "What about last-minute plane substitutions, where instead of 12 rows for families you suddenly have only 7?"And like many people, Mr. Castelveter points out that separating passengers based on age puts the airlines on a slippery slope. Does anyone really want to be forced to sit in the obese-only section? Why not elderly-free flights?Mr. Castelveter said he has heard the discussion around the issue, but insists it's only a "small minority" who are complaining. He says he has heard no discussion about the topic among the airlines.Indeed, in what is perhaps a sign of just how sensitive the topic is, neither Delta, Southwest, AirTran, US Airways nor Qantas replied to requests for comment for this article. An American Airlines spokeswoman said only, "We do not offer child-free flights" in an e-mail message.Which still doesn't mean it couldn't happen. Should demand for child-free flights reach critical mass, there is nothing stopping some crafty entrepreneur from launching an adults-only airline. Sound far-fetched? Consider that Pet Airways now offers "pawsengers" weekly flights to several American cities. And even Hooters Air, which brought the restaurant's winning formula of buffalo wings and under-dressed waitresses to the sky, generated enough interest to survive from 2003 to 2006.Until then, it is perhaps best to heed the advice of Anya Clowers, a registered nurse and proprietor of JetWithKids.com, a blog about flying drama-free with children."Everyone has to do their best to self-contain," she said. For parents, that means anticipating your child's needs, such as snacks, distractions and sleep. If your child is old enough, consider giving him or her a role during the flight, she said, such as official seat belt fastener. And inquire about sitting in the last row of the plane, where your child "won't have as much of an audience," should he or she act up.The most important thing for parents to do is stay calm, said Mrs. Clowers, who says she has taken her 6-year-old son to 17 countries without incident. "Kids pick up on their parents' stress," she said. Avoid letting the hassles of air travel get to you, and you just might head off a tantrum.

That goes for childless travelers, too. "They need to respect that this may be someone's family vacation, or someone may be going to their parents' funeral," Mrs. Clowers said.So consider traveling with noise-canceling headphones, she advised, "and try to remember: plenty of business travelers are annoying, too."