2 Planes Crash Mid-Air at Air Show at Dallas Executive Airport

Two World War II-era airplanes collided in midair at an air show in Dallas on Saturday, the authorities said, turning the commemorative Veterans Day weekend event into a scene of horror.

It was not immediately clear how many people were aboard when the planes — a Boeing B-17 Flying Fortress and a Bell P-63 Kingcobra — crashed at about 1:20 p.m. local time, the Federal Aviation Administration said. The crash happened at the Wings Over Dallas air show at Dallas Executive Airport, which is about 10 miles south of downtown Dallas.

Videos posted online appeared to show a fast and agile airplane slamming into a larger aircraft as horrified onlookers watched.

Paul Martin, a member of the Army Air Forces Historical Association, said that the Flying Fortress was a bomber airplane that was lumbering and like a “tractor-trailer truck,” big enough to carry a crew of 10 or 11 people, while the Kingcobra was a single-pilot fighter plane.

To have either aircraft in flying condition is a rare occurrence, he said. There are fewer than a handful of either in that condition, he said.

“It’s heartbreaking for me to hear this, both on a human level and a historical level,” he said.

The F.A.A. and the National Transportation Safety Board will investigate the crash, the F.A.A. said.

Dallas Mayor Eric Johnson said on social media on Saturday that there were no reports of injuries to spectators or those on the ground. He said that much about the crash remained unknown or unconfirmed.

“The videos are heartbreaking,” he said. “Please, say a prayer for the souls who took to the sky to entertain and educate our families today.”

In 2019, another B-17 bomber was destroyed in a deadly crash. Seven people were killed in after a Flying Fortress that took off from Bradley International Airport, near Hartford, Conn., crashed into a de-icing facility shortly after takeoff, according to the National Transportation Safety Board. The agency found that pilot error and inadequate maintenance contributed to the crash.

Christopher Kratovil, a lawyer in Dallas, took his 12-year-old daughter, Kelsey, a history buff like himself, to the air show on Saturday. Mr. Kratovil said his father used to take him to air shows when he was a child.

“It’s just an amazing thing to see these aircraft that you read about in the pages of a history book, there and tangible, and you see them flying and operating,” he said.

He said there were several aircraft flying at the same time, perhaps about eight, a mix of bombers like the Flying Fortress and fighters like the Kingcobra. The event included a narrator describing the significance of the aircraft, with patriotic music playing in the background.

Mr. Kratovil said the Flying Fortress appeared to be doing a flyby near the crowd, a common move meant for attendees to get a good look.

Then he saw the explosion.

His first thought was it could be pyrotechnics, but he quickly realized there was no way to do midair pyrotechnics. He then saw a wing come off the B-17 and then the fuselage of the plane fall to the ground, followed by fireballs and a loud crash.

“It hit me all of a sudden: This is real. You’re watching a B-17 crash,” he said. “It was just a horrific thing to see and a horrific thing to witness with one of my children.”