Here's what United, Southwest, and American Airlines are doing after the US grounded all Boeing 737 Max planes

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A Boeing 737 Max takes part in a flyng display at the first day of the 52nd Paris Air Show at Le Bourget airport near Paris

• The United States joined Europe and others in grounding all Boeing 737 Max  airplanes on Wednesday. 
• Around the world, hundreds of flights have been canceled after the plane was involved in second deadly crash on Sunday in Ethiopia. 
• Southwest, American, and United Airlines operate the plane in the United States. 

President Trump announced Wednesday that the United States would join Europe and many other countries in grounding all Boeing 737 Max airplanes after the model was involved in a second deadly crash on Sunday.

At the time of Trump's announcement, dozens of the planes - operated by American, Southwest and United - were still airborne. The FAA confirmed that it was ordering the temporary grounding of Boeing 737 Max aircraft "operated by US airlines or in US territory."

American Airlines said in a statement to Business Insider that it had 24 aircraft affected by the directive and was "working to rebook customers as quickly as possible."

At least six American flights were canceled between New York's LaGuardia Airport and Miami. It's possible that the so-called red-eye cross-country flights Wednesday evening could also be affected.

Southwest Airlines, which earlier on Wednesday had said it had waived change fee and was working with passengers who wanted to avoid flying on the aircraft in question, said it was "seeking confirmation and additional guidance from the FAA."

Southwest has the largest exposure to the aircraft, with 34 of the planes.

United Airlines, which operates 14 737 Max 9's, said it would have to cancel 40 flights per day.

"We do not anticipate a significant operational impact as a result of this order," a spokesperson told Business Insider. "We will continue to work with our customers to help minimize any disruption to their travel."

Boeing's chief executive Dennis Muilenburg said in a statement that the company had consulted federal authorities and recommend the temporary restriction to the FAA "out of an abundance of caution."

"We are supporting this proactive step out of an abundance of caution," the statement read. "Safety is a core value at Boeing for as long as we have been building airplanes; and it always will be. There is no greater priority for our company and our industry. We are doing everything we can to understand the cause of the accidents in partnership with the investigators, deploy safety enhancements and help ensure this does not happen again."

More on Boeing's 737 Max 8 and the Ethiopian Airlines disaster: 

• Everything we know about Ethiopian Airlines' deadly crash of a Boeing 737 Max 8, the second disaster involving the plane in 5 months
• Norwegian Air reportedly tells Boeing to 'take this bill' after grounding its fleet of 18 Boeing 737 Max planes
• This map shows all the countries to ban the Boeing 737 Max 8, and where airlines have grounded their fleets, after Ethiopian Airlines crash that killed 157
• Elected officials are calling on the US government to ground the Boeing 737 Max 8 after the plane was involved in 2 deadly crashes
• Boeing's CEO reportedly asked President Trump not to ground the company's plane that has crashed twice in 5 months
• Pilots complained to authorities about issues with the Boeing 737 Max for months before the deadly Ethiopian Airlines crash
• The US government says it has no reason to ground the Boeing 737 MAX that has crashed twice since October
• These airlines will likely take the biggest hit after the Boeing 737 Max was involved in two deadly crashes
• The Boeing 737 Max has come under fire after 2 deadly crashes in 5 months - but the aircraft is likely to be successful in the long-run, an aviation expert explains
• These airlines will likely take the biggest hit after the Boeing 737 Max was involved in two deadly crashes
• 'You basically put a student pilot in there': The copilot of crashed Ethiopian Airlines Flight 302 had just 200 hours of flight experience
• Boeing is going to update the control software on the 737 Max that may cause the plane to nosedive
• Boeing has $400 billion in orders on the books, 80% of them are for the 737
• 'I don't want Albert Einstein to be my pilot': Trump says airplanes are becoming 'too complex to fly' as the UK, China, and other nations ground the Boeing 737 Max 8
• These are the victims of the Boeing 737 Max 8 crash in Ethiopia
• The family of Ethiopian Airlines Flight 302 captain speaks out after crash that killed 157 people
• A Georgetown University law student who reportedly expressed a fear of flying is among the 157 dead in the Ethiopian Airlines crash
• The black box from the crashed Ethiopian Airlines flight has been found
• An Ethiopian Airlines passenger said he missed the crashed flight by 2 minutes: 'I'm grateful to be alive'
• People of 35 different nationalities were killed in the Ethiopian Airlines crash, including 8 Americans

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