Delta Air Lines (NYSE:DAL) said Wednesday that it will prevent travelers from selecting middle seats and cap passenger counts on flights through Sept. 30, its latest effort to reassure passengers it is safe to fly without a COVID-19 vaccine.

Delta said it will sell only 50% of first class seats and between 60% and 75% of seats in other classes to help give passengers more space and to allow for some form of social distancing in flight. The airline is also restarting automatic upgrades for frequent travelers and has pledged to add flights on routes where the planes are nearing the caps.

A Delta jet parked on the tarmac.

Image source: Delta Air Lines.

"Reducing the overall number of customers on every aircraft across the fleet is one of the most important steps we can take to ensure a safe experience for our customers and people," Bill Lentsch, Delta's chief customer experience officer, said in a statement. "Delta is offering the highest standards in safety and cleanliness so we're ready for customers when they're ready to fly again."

Delta and other airlines saw travel demand fall 95% or more year over year in April and early May as the pandemic intensified, but the industry is beginning to see the early signs of a recovery. Airlines are trying to do what they can to encourage flying, including requiring customers and employees to wear face coverings, installing plexiglass at various points where customers and employees interact, and taking these in-flight steps.

The goal, for now, is to get as many people as possible flying during the usually busy summer months and then reassess in the Fall. Sept. 30 is also the end of government restrictions on layoffs included as part of the CARES Act bailout plan, so Delta and other airlines by September will have to look at demand and make decisions about packing flights more full and projecting future headcount needs.