The FAA has launched an investigation into a loss of separation between two commercial flights in Phoenix Saturday.

The Federal Aviation Administration is investigating after a United Airlines flight and a Delta Airlines flight had a near-collision over Phoenix on Saturday.

A Delta Air Lines plane and a United Airlines aircraft raised alarms when they flew too close to each other while flying into Phoenix on Saturday. The Federal Aviation Administration is investigating the “loss of required separation” incident.

The two flights, United Airlines Flight 1724 and Delta Air Lines Flight 1070 came too close to each other while arriving at the airport.

The Federal Aviation Administration is investigating a narrowly missed midair collision between a United flight and a Delta flight at Phoenix Sky Harbor International Airport on Saturday, the agency said.

The United and Delta flights were less than a quarter of a mile apart horizontally before the warning devices went off, officials say.

We are just a few steps from the finish line. We want to turn what are now one- and two-hour trips into five-minute trips.”

Authorities in Monterey County, California lifted all evacuations Friday night, one day after a fire broke out at one of the world's largest lithium battery storage facilities.

The incident in which a SpaceX rocket broke up after launch demonstrates the challenges the FAA will face as the number of commercial space flights increases.

Alaska Airlines is the only United States-based carrier that was in AirlineRatings' top 10—although Hawaiian, American, Delta and United were in the top 25.

Hawaii and Texas residents showed up to an FAA meeting to oppose the SpaceX plan to increase the number of launches and landings per year.