Faa Investigates Possible Collision Avoidance Instrument Issues Near Dca

Common flight maneuvers that might feel unsettling but are normal

Here are three surprising flight maneuvers that feel dangerous but are completely safe.

The Federal Aviation Administration is investigating after multiple pilots preparing to land at Ronald Reagan Washington National Airport received faulty warnings about possible obstacles in their flight paths on Saturday.

"Several flight crews inbound to Reagan Washington National Airport received onboard alerts Saturday indicating another aircraft was nearby when no other aircraft were in the area. Some of the crews executed go-arounds as a result of the alerts. The FAA is investigating why the alerts occurred," the agency said in a statement to USA TODAY.

No injuries or other concerns were reported, but experts say the malfunction is unusual.

"I've never heard of something like this," Robert Sumwalt, former chair of the National Transportation Safety Board, told CBS News, which first reported the story. "Nuisance alerts, yes, they happen. But not like this where several planes have it at the same location."

Still, pilots all appear to have followed the appropriate procedures when they received the alerts.

The airspace around National Airport has been under heightened scrutiny since a mid-air collision between an Army Black Hawk helicopter and an American Airlines regional jet that was preparing to land at the airport in January.

Zach Wichter is a travel reporter and writes the Cruising Altitude column for USA TODAY. He is based in New York and you can reach him at zwichter@usatoday.com.