American Airlines is taking its Boeing 737 Max planes out of storage and preparing them to return to service.

To encourage passengers to fly on the planes the company said that it will be flying some of the planes across the country with its top executives, employees, and reporters on board this week.

The return of the airplanes comes after 20 months of forced global groundings by aviation regulators following two crashes that killed 346 people. The airline said that it understands that people are apprehensive about boarding the planes but it has assured the public that the aircraft is now safe.

"You don't build confidence when the plane sits on the ground. You build confidence when it's out there flying and it's doing the job it's intended to do," American Airlines' chief operating officer David Seymour said.

American Airlines said that customers will be able to view the jets at various airports before they are brought back to commercial service. All Boeing 737 Max planes, which have been fitted with software and hardware fixes, had been approved to return to service by the Federal Aviation Administration.

The airline currently has 24 Boeing 737 Max jets, which were all grounded after the crashes.

American Airlines will become the first U.S. carrier to resume commercial flights using the 737 Max. The company said that the first commercial flight with paying passengers will be Dec. 29 between Miami and New York's LaGuardia Airport.

To prepare its pilots and crew members for the return of the planes, the airline will be holding new pilot training starting this week. The training will include changes made by Boeing on its autopilot systems.

Pilots will be using flight simulators and learning new computer-based instructions - a step that was previously not required for pilots who had already flown older Boeing models.

During the investigations into the two crashes, it was found out that Boeing's computer-based flight-control system was to blame for both instances. Boeing said that it had already corrected the mistake and the software changes should give pilots more control of the aircraft. The company said that it has also added more redundancies - among other changes - that were approved by the Federal Aviation Administration.