More than three decades ago, a United Airlines jet crashed in Portland, killing 10 people, because the co-pilot and flight engineer didn’t speak up. The captain ignored the flight engineer’s warnings that the plane didn’t have enough fuel to land safely. As the tanks ran dry, the junior crew members said nothing, the National Transportation Safety Board found.

The events aboard a Tuesday JetBlue flight, on which the co-pilot locked an erratic captain out of the cockpit and diverted the plane to a safe landing, show how much has changed in a culture once typified by autocratic captains, safety specialists said. The co-pilot was identified Thursday as Jason Dowd of Salem, Ohio.

“Thirty years ago, I doubt you would have found a co-pilot who would have done this because of fear of going up against a captain and fear of getting fired,” said John Nance, a former commercial pilot who now runs a Seattle-based safety consulting firm.

The United accident prompted a revolution in how pilots are trained, said Frank Tullo, an airline safety officer who helped devised new methods designed to give all crew members responsibility for safety.

Co-pilots were taught to speak up if they had concerns. Captains, many of whom had come from the military, where officers were always considered to be right, were instructed to listen and encourage others to voice concerns.

The training, known as crew resource management, is now required by the U.S. Federal Aviation Administration.

Tullo said the JetBlue crew’s actions were a good example of that training being used in an unusual emergency that probably hadn’t been rehearsed.

Examples included the flight attendants seeking help early in the disturbance from passengers if things got worse, and the off-duty captain responding to crew requests for assistance, Tullo said.

JetBlue Captain Clayton Osbon, charged Wednesday with interfering with a flight crew, was tackled by passengers as he pounded on the cockpit door after leaving and then demanding to be let back in, according to an FBI affidavit.

The co-pilot became concerned about Osbon’s behavior shortly after the flight to Las Vegas left New York. The captain had yelled over the radio at air-traffic controllers and rambled about religion, according to the FBI. Shortly thereafter, the co-pilot suggested that they invite the off-duty captain to join them, according to the affidavit. Osbon reacted by leaving the cockpit.

With Osbon walking the aisle and ranting, the crew took several steps critical to ensuring their safety, Tullo said.

The co-pilot told a flight attendant to bring the off-duty captain into the cockpit.

When Osbon began banging on the cockpit door to get back in, the co-pilot made an announcement over the public address system asking passengers to restrain Osbon. The pilots in the cockpit also locked the bulletproof door to prevent Osbon from using a code to reenter, according to the FBI.

“This is a home run,” said Tullo. “We have really empowered the entire crew to be responsible for the safe conduct of the flight.”