SAN FRANCISCO—Midway through American Airlines flight 1544’s journey from San Francisco to Dallas Monday, pilot Mark Dams asked passengers to please remain seated and fasten their seat belts for a minute while he tries something real quick. “Attention passengers, bear with me for a moment; I just want to try a little something here,” Dams announced over the plane’s intercom, adding that he “heard about another pilot doing this once” and wants to see if it actually works. “Should only take a few seconds. I just want to see what happens.” At press time, Dams reportedly took a breath and muttered to himself, “Okay, here goes.”