US safety regulators have cleared Boeing's 737 Max plane to fly again, lifting grounding orders put in place in March 2019 after two deadly crashes.
It marks a milestone for Boeing which was thrust into crisis by the tragedies and investigations that blamed company failures for the accidents.
Its financial woes deepened this year as air travel slowed due to the virus.
Existing aircraft will need to be modified before going back into service, with changes to their design.
Safety regulator, the US Federal Aviation Administration (FAA), said the clearance would not allow the plane to "return immediately" to the skies.
Alongside the software and wiring changes, pilots will also need training.
The FAA said the design changes it had required "have eliminated what caused these particular accidents".
The boss of the FAA said he was "100% confident" in the safety of the plane.
"We've done everything humanly possible to make sure" these types of crashes do not happen again," Steve Dickson said.
As well as improvements to the plane, Boeing chief executive Dave Calhoun said the company had strengthened its safety practices and culture since the disasters.
"We will never forget the lives lost in the two tragic accidents that led to the decision to suspend operations," said Mr Calhoun, who took over when his predecessor, Dennis Muilenburg, was fired last year.
"These events and the lessons we have learned as a result have reshaped our company and further focused our attention on our core values of safety, quality and integrity."
