Carriers diverge on whether to maintain social distancing and run aircraft at partial capacity.
Flying with empty middle seats means airlines will struggle to turn a profit, creating a dilemma for an industry desperate to revive itself while also reassuring passengers they are safe.
US airlines saw some demand for travel return this summer, though it has stalled as new Covid-19 cases continue to rise in southern and western states.
American Airlines told passengers to expect fully booked planes on July 1, including middle seats. The company had previously attempted to leave some seats empty for social distancing.
Anthony Fauci, a leading member of the White House coronavirus task force, panned the decision. Oregon senator Jeff Merkley said he would introduce a bill to block the practice and celebrity cookbook author Chrissy Teigen garnered 88,000 likes for a tweet that said the airline “only cares about money”.
Selling more seats would help airlines stem their losses, which ranged from $94m to $2.2bn among major US carriers in the first quarter. Delta Air Lines, the only US airline so far to report second-quarter results, posted a $7bn pre-tax loss.
To break even on a flight, airlines need to sell about 75 per cent of a plane’s seating capacity. That is 8 percentage points higher than an aeroplane where every third seat is empty.
“If you leave the middle seat empty . . . you’re not going to make money,” said Kevin Michaels, managing director of AeroDynamic Advisory.