A device that automatically helps planes reduce speed on landing was not functioning on the campaign plane carrying Republican vice-presidential nominee Mike Pence that ran off the end of a runway Thursday night at LaGuardia Airport, a federal safety official said Friday.

The spoilers on the planes’ wings that create drag normally deploy automatically about one second after landing, but had to be deployed manually by the pilot of the Pence plane about four seconds after touch down, the official said.

The automatic feature on the device, called a speed brake actuator, had been inoperable for two days, said Robert Sumwalt, a member of the National Transportation Safety Board. It was not known whether the pilot of the plane was aware of the problem, and Sumwalt said the crew would be interviewed Saturday.

Sumwalt, during a news conference at the Queens airport, did not provide any more information on that point. He said the board is not yet giving a cause of the accident.

Investigators have not pinpointed the spot on the runway where the plane touched down, but the plane’s approach speed was 130 knots (about 150 mph) at the time, which Sumwalt said “does not appear to be out of the ordinary to me.” He said the speed at touch down was 122 knots.

The Boeing 737-700 was on lease from Eastern Airlines, a charter air service that could not be reached for comment.

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Sumwalt said the flight recorder was recovered from the plane and sent to the NTSB lab in Washington, D.C., for examination.

The plane landed on a rain-slicked runway about 7:42 p.m. Thursday was brought to a halt about 200 feet past the end of the runway after entering a bed of crushable material that slows the wheels of a plane.

Pence appeared on several morning television news shows Friday and called the landing “10 seconds of uncertainty.”

“When we landed, it was obvious I think to everybody on the plane that the pilots were hitting the brakes very hard,” Pence, the governor of Indiana, said on one show.

He and his campaign staff left aboard another leased plane later Friday for appearances in Pennsylvania and North Carolina.

The plane, which had taken off hours earlier Thursday from an airport in Fort Dodge, Iowa, after a Pence rally there, carried 37 passengers and 11 crew members, Port Authority officials said.

The website liveatc.net carried audio of an air traffic controller watching the landing and saying: “Eastern stop. Stop Eastern,” a reference to the Pence plane’s designation as Eastern Flight 3452.

The controller then directed other planes waiting to land to “go around,” meaning they should not land. “The airport is closed,” the controller said.

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Passengers said as the aircraft flew over the city in preparation to land, it knifed through hard rain, strong winds and thick fog. Turbulence jostled the twin-engine jet.

When the plane touched down on the 7,000-foot runway, it vibrated and then jerked violently while sliding, a passenger said.

“You could feel the plane skidding,” CNN producer Elizabeth Landers, who was seated in the back of the plane, said in an interview on the network. The plane “felt like it fishtailed.”