U.S. Southwest Airlines lowers revenue outlook on Boeing 737 Max groundings

Southwest airlines, a major U.S. airline, cut its revenue forecast on Wednesday, citing the grounding of its Boeing 737 Max planes.

In a regulatory filing, the airline said it expects to cancel 9,400 flights through the end of March, along with a loss of 150 million U.S. dollars in revenue, due to the grounding and weather disruptions, among other causes.

The Dallas, Texas-based company also said its "available seat miles," an industry metric that measures an airline's capacity, will increase 1 percent in the first quarter, down from a previous forecast of 3.5-percent to 4-percent growth.

The global fleet of 737 Max jets was grounded indefinitely this month following a deadly Ethiopian airlines crash that killed 157 people on board. A few months earlier, a plane of the same type, went down in Indonesia, leaving 189 people on board dead.

Southwest, which owns 34 of the aircraft, said it couldn't estimate the impact of the grounding beyond the first quarter.

"As of today, the Company has reduced its published flight schedule through April 20, 2019, and is currently evaluating future schedule reductions," it said in the filing.

On Tuesday, a Southwest airlines Boeing 737 Max on its way to be grounded made an emergency landing at the Orlando International Airport.

The plane, with only a pilot and a co-pilot on board, experienced an engine malfunction shortly after takeoff before landing safely.

The deadly crashes have also put the oversight of the Federal Aviation Administration (FAA), the U.S. watchdog, on civil aviation safety under scrutiny.

Calvin Scovel, the U.S. Department of Transportation's inspector general, told a Senate hearing Wednesday that the FAA was going to have significant change to its oversight approach by July.