Parents have noticed. “You don’t have to have ‘Leave it to Beaver’ on, but for Pete’s sake, you don’t have to have Eva Longoria seducing the high school kid on the dining room table, either,” said Timothy Winter, president of the Parents Television Council, which offers parents advice on program selections. Mr. Winter said he received weekly complaints about airline movies from parents, whereas last year he received none.

Mr. Kleiman, of Continental, said that at times there were not enough popular romantic comedies and other lighter movies to fill the available slots in his airplanes. When an airline chooses to feature R-rated movies, he said, movie studios send an uncut version to the airlines, along with a list of suggested cuts.

Jeff Crawford, who oversees the division of Warner Brothers that markets movies to airlines, said his editors “know what to do,” adding, “They’re doing it both for the airline and for TV, down the road, where we’d obviously try to tone down the graphic violence or blood.”

Nina Plotner, an account manager with Inflight Productions Inc., which works on behalf of many airlines to review and acquire films, said of the editing procedure, “If we take all the good things out, there’s not going to be a lot left to play.”

Ms. Plotner added: “If you get a complaint, you get a complaint. You can’t please everybody.”

Mr. Kleiman, of Continental, agreed, saying: “People love Pepsi, and we don’t serve that, so there you go, we just ruined their flight. That’s an accurate analogy.” Airlines said they received relatively few complaints.

The debate about suitable content in airlines comes against the backdrop of a continuing debate about movie violence in Hollywood. Researchers have determined, for example, that standards for films rated PG-13 (parental guidance suggested for those 13 and under) have become more lax in recent years, with such films often featuring violence, sexual situations and profanity that would have been R-rated (suitable for age 17 or over) a decade ago. Indeed, many airline movies cited by parents and critics have been rated PG-13, including “King Kong.”

Shari Maser of Ann Arbor, Mich., spent part of last year sitting up at night with her 7-year-old daughter, who had nightmares after seeing a preview for “King Kong” on a US Airways flight. It showed people being attacked by dinosaurs.