DETROIT - They heard a pop that sounded like fireworks. They saw a glow of flame followed by a rush of smoke. And that was enough for passengers on Northwest Airlines Flight 253 to pounce.

Dutch tourist Jasper Schuringa said that, from several seats away, he jumped to extinguish a fire ignited by a quiet man who, just moments before, allegedly told fellow passengers that his stomach was upset and pulled a blanket over himself. Schuringa said his first thought wasn't to signal a flight attendant or wait for an air marshal to break cover, but rather: "He's trying to blow up the plane."

"I basically reacted directly," Schuringa told CNN yesterday. "I didn't think. I just jumped. I just went over there and tried to save the plane."

Aviation-safety experts once would have called Schuringa's actions a mistake and would have cautioned passengers against fighting back during hijackings and other crises in the air. That was before the Sept. 11, 2001, attacks and the actions of passengers on United Airlines Flight 93, who learned while aloft about the hijacked jets that slammed earlier that day into New York's World Trade Center.

They staged a cabin revolt against the al-Qaeda terrorists who had taken control of their flight, and all aboard died when the plane crashed into a field in Shanksville, Pa. But they succeeded in keeping it from destroying another building that day, and their story became legend.

"I don't think people are going to sit back and let somebody kill them in the process of fulfilling their extremist agenda, or whatever it happens to be," said Dave Heffernan, who helps oversee self-defense training for commercial flight crews at Valencia Community College in Orlando. "People have talked about it. They've thought about it. They have a plan of action."

Yesterday, Umar Farouk Abdulmutallab, 23, a native of Nigeria, was charged with trying to destroy the Northwest jet with a device containing a high explosive attached to his body.

Schuringa, of Amsterdam, told CNN that he didn't think about his own safety when, with his hands, he extinguished the fire set off by Abdulmutallab's actions. Schuringa and other passengers said that several people onboard, including members of the flight crew, then joined him in taking Abdulmutallab to first class to strip off his clothes and search for more explosives.

"The passengers were proactive. We just did it. There was nothing to talk about," said passenger Syed Jafry, 57.

Another passenger, Richelle Keepman, 24, of Oconomowoc, Wis., said passengers were later interviewed by authorities and released from the airport. When Schuringa came through the area, she said, "we were all clapping."

Schuringa joins the passengers on United 93 and others since who have leapt into action to defend themselves aloft. Just three months after 9/11, Briton Richard Reid was overpowered by passengers and crew members on a flight from Paris to Miami as he tried to ignite plastic explosives hidden in his shoes. A doctor onboard went so far as to inject the restrained Reid with a sedative.

Passengers aren't responding only to obvious acts of terror. In June, two off-duty officers handcuffed a traveler who had taken off his clothes and kicked and punched a flight attendant on a US Airways flight from Charlotte, N.C., to Los Angeles. In April 2008, passengers duct-taped a drunken man to his seat after he attacked a United flight attendant on a trip from Hong Kong to Los Angeles.

"Aggressive intervention has become the new societal norm," said Bill Voss, an expert at the Flight Safety Foundation in Alexandria, Va.

Jennifer Allen, 41, of Shelby Township, Mich., who arrived in Detroit on yesterday's Northwest Flight 253, said: "We're not so blase, not so willing to accept that we're safe, and we can let someone do our security for us.

"We're not going to sit there and wait for somebody else to do it," she said, "because if you wait, it might be too late."