Arguments, fights and meltdowns have been a part of commercial airline service for decades, but airborne conflicts have become viral internet sensations in the past few years, now that nearly every flyer is armed with a smartphone and access to social media. “It has changed the dynamics of what happens in our planes and at our gate areas,” said Suzanne Boda, American Airlines’ senior vice president for Los Angeles. For that reason, the Fort Worth-based carrier is requiring all flight attendants and employees who deal with customers to take training on how to de-escalate conflicts with passengers. That applies to about 65,000 American Airlines employees. The addition of such training had been discussed at the airline for months but became a priority after an incident in April when a feud broke out between a flight attendant and a passenger over a baby stroller. As has been the case with other cabin imbroglios, it was caught on camera and posted on the internet. “These things happen,” Boda said.