Delta Air Lines (DAL) posted a nearly $3 billion loss in the first quarter as the battered airline industry continued to dig itself out from the deep hole created by the COVID-19 pandemic, but saw revenues climb as travelers slowly return to the skies.

Here were the main results from the Q1 report, compared to consensus estimates compiled by Bloomberg:

• Total Q1 operating revenue: $4.2 billion vs. $3.94 billion expected

• Adjusted pre-tax loss: $2.9 billion vs $2.25 billion expected

• Adjusted loss per share: $3.55 vs. $3.17 expected

• GAAP loss per share: $1.85 vs. $2.70 expected

• Adjusted operating revenue $3.6 billion

The airline hit a big milestone in March, when its quarterly average daily cash burn, $11 million, turned positive, generating $4 million per day. As the COVID-19 mass vaccination effort hits its stride — especially in the U.S. — passengers have been flocking to airports en masse.

In an interview with Yahoo Finance, CEO Ed Bastian told Yahoo Finance he sees a pathway to profitability even though the airline lost billions. “Our goal will be this summer, which will go from June through Q3 to turn this company profitable and I think we've got a pathway to do that,” Bastian said.

Bastian added the airline has turned the corner on the worst crisis in its history.

“I expect as we look at bookings going forward that recovery, the face of the recovery is going to continue to improve. And certainly for the second quarter, we expect to be cash positive yet again," he told Yahoo Finance.

Still, Delta faces turbulence in the second quarter, predicting its scheduled capacity will be down 32% compared to 2019 and its total revenue will be down 50% to 55%.

Part of that decline is Delta’s decision to continue blocking middle seats through the end of April on all its flights, but Bastian expects passengers to continue booking tickets as confidence grows among Americans receiving the COVID-19 vaccine.

“It appears it may still be six or more months out before we start to see international travel starting to pick up and the recovery to corporate business," Bastian explained. "We're still in a relatively muted state around corporate travel only about 20% of what it ought to be."

However, Delta has been using the pandemic downturn to streamline its fleet of jets and prepare for the recovery.

Why older planes are 'still economically viable'

As the company continues its rebound and idled planes take flight again, the age of Delta's fleet has come into focus. The Boeing (BA) 737 is the workhorse of Delta's fleet, and its fleet of 207 travel more than any other in its hangers.

Delta flies 77 Boeing 737-800 jets with an average age of almost 20 years, while flying 130 of the newer 737-900ER. For the latter, the average age is roughly 4 years.

"Today, a 20-year old 737-900 is still economically viable, and from the consumer experience no different from a brand new 737MAX," according to airline industry consultant Mike Boyd.

He explained to Yahoo Finance that airlines "literally tear the planes down and re-build" them to comply with FAA safety regulations, which makes the age of a plane somewhat misleading.

"If we took care of cars like airlines do airplanes, we’d all be driving ’57 Chevys as the technologies in a 20 year old Airbus A320 are only incrementally different than a new one," he said.

Delta however announced plans at the end of 2019 to modernize and eliminate "complexity with fewer aircraft types." The COVID-19 pandemic allowed Delta to accelerate those plans, which saw the carrier permanently ground 47 MD-88 jets — the oldest aircraft in the Delta fleet with an average age of nearly 29 years.

Currently, Delta flies 750 aircraft, down from almost 1000 in 2019, and the airline has committed to purchase or lease 223 new planes — all from Boeing's European rival Airbus.

"It's important as the largest airline or one of the largest airlines in the world that we have a strong relationship with both Boeing and Airbus," Bastian said. It's more efficient for staffing and simpler for customers he added.

Adam Shapiro is co-anchor of Yahoo Finance Live 3pm to 5pm. Follow him on Twitter @Ajshaps

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