Dennis Shirshikov recalls a recent American Airlines flight from Mexico City to New York with his wife and three young children. As they boarded, a crew member ordered him to gate-check their stroller. Shirshikov, who runs a real estate investment firm in New York, says he balked because the stroller was regulation-size and he needed it to transport his kids. "They were very confrontational," he says. When he arrived at JFK, the stroller was gone. He finally found it in the lost and found.

Southwest retreated 1 percent to 79, tied for second place with JetBlue (which was unchanged). Since 2012, the two airlines have taken the top spots in the ACSI ratings, joined by a steadily improving Alaska. "Recent deadly crashes of the Boeing 737 Max for Ethiopian Airlines and Air Lion have left Southwest particularly vulnerable to safety concerns," says VanAmburg. (Southwest operates an all-737 fleet.)