President Donald Trump on Thursday blamed last week’s deadly collision of a passenger jet and Army helicopter on what he called an “obsolete” computer system used by U.S. air traffic controllers, and he vowed to replace it.

Trump said during an event that “a lot of mistakes happened” on Jan. 29 when an American Airlines flight out of Wichita, Kansas, collided with an Army helicopter as the plane was about to land at Ronald Reagan National Airport near Washington, killing all 67 people on board the two aircraft.

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In the immediate aftermath of the tragedy, Trump blamed diversity hiring programs for the crash. But on Thursday, he blamed the computer system used by the country’s air traffic controllers.

“It’s amazing that it happened,” Trump said during a speech at the National Prayer Breakfast at the U.S. Capitol. “And I think that’s going to be used for good. I think what is going to happen is we’re all going to sit down and do a great computerized system for our control towers. Brand new — not pieced together, obsolete.”

Trump said the U.S. spent billions of dollars trying to “renovate an old, broken system” instead of investing in a new one. He said in his own private jet, he uses a system from another country when he lands because his pilot says the existing system is obsolete.

Federal officials have been raising concerns about an overtaxed and understaffed air traffic control system for years, especially after a series of close calls between planes at U.S. airports. Among the reasons they’ve cited for staffing shortages are uncompetitive pay, long shifts, intensive training and mandatory retirements.

Trump said that if the nation had a newer system, alarms would have sounded when the Black Hawk helicopter, which was on a training exercise, reached the same altitude as the plane.

But an FAA report after the crash said that the controller did get an alert that the plane and helicopter were converging when they were still more than a mile (1.6 kilometers) apart. The controller responded by asking the helicopter if it had the plane in sight and directed the helicopter to pass behind the plane. The helicopter responded that it did have the plane in sight.

An early focus of the investigation has been confirming the altitude of the plane and helicopter. The jet’s flight recorder showed its altitude as 325 feet (99 meters), plus or minus 25 feet (7.6 meters).

Data from the airport’s air traffic control system suggests the helicopter was above its 200-foot (61-meter) flight ceiling. The screen the controller was looking at that night showed that based on radar and other data, the helicopter was at 300 feet (91 meters), the NTSB said, noting that the figure would have been rounded to the nearest 100 feet (30 meters).

To get more precise information, investigators need to be able to examine the wreckage of the still-submerged Black Hawk to verify the data. The helicopter isn’t expected to be recovered until later this week.

This crash was the deadliest in the U.S. since Nov. 12, 2001, when a jet slammed into a New York City neighborhood just after takeoff, killing all 260 people on board and five on the ground.

There was concern after the crash that Trump’s efforts to slash the size of the federal workforce could worsen the shortage of air traffic controllers if some of them accepted the deferred resignation offers sent to all federal employees last week. But air traffic controllers were told by their union Thursday that certain positions within the Federal Aviation Administration, including theirs, were exempt.

The National Air Traffic Controllers Association said in its email to members that additional positions might be exempt based on the employees’ “national security or public safety responsibilities.” The union had already recommended to its members that they reject the offers, which were extended the day before the midair collision. ___
Associated Press reporters Aamer Madhani, Adriana Gomez Licon and Thomas Beaumont contributed to this report.