Avia Solutions Group has ordered 40 737 MAX 8 aircraft from Boeing, the companies said Tuesday, in a transaction valued at about $4.9 billion -- a boost to the aviation giant as it recovers from a worker strike.

Avia's first firm order with the aviation giant comes with an option to add another 40 jets later, Boeing and Avia said in a statement.

"We have committed to a strategic approach of expanding our capacity to meet our customers' seasonal needs, and our first order with Boeing is a key pillar of this," said Gediminas Ziemelis, chairman of the aviation services group.

The purchase announcement came shortly after striking workers at Boeing last week approved a new contract proposal, ending a more than seven-week stoppage that cost Boeing billions.

The end of the strike sends about 33,000 Seattle-area employees back to work and restores operations at two major assembly plants, at a time when Boeing is trying to recover from multiple setbacks.

The factories affected built the 737 MAX and 777 aircraft.

The versatile 737 family is among Boeing's best-sellers. The 737 MAX 8 can seat 162 to 210 passengers -- with a range of up to 6,480 kilometers (about 4,000 miles).

The strike at Boeing exacerbated the company's already-precarious outlook after a January incident in which a fuselage panel blew out mid-flight on a 737 MAX operated by Alaska Airlines.