Remember that major systems outage that hit Delta last month, prompting the airline to ground all flights worldwide? In addition to majorly ticking off customers who had their travel plans disrupted and grabbing the attention of lawmakers who have since demanded an explanation for these kinds of outages, Delta lost a whole lot of money.

Four days of canceled and delayed flights comes out to a $100 million loss of revenue, Delta said on Friday, or about 1% of its quarterly revenue, notes the Minneapolis Star Tribune. All told, Delta had to cancel about 2,300 flights after a power failure brought down the company’s systems.

The financial impact of the outage doesn’t just affect revenue: Delta likely had to shell out a big chunk of change to cover travel vouchers, hotel accommodations for stranded travelers, worker overtime pay, and other things. Those expenses will probably be reported during Delta’s third-quarter results in October.

On a brighter note, at least where Delta is concerned, the airline completed 98% of its scheduled flights last month (not including regional affiliates).

“We are grateful to our customers for continuing to rely on Delta for the superior customer service and operational performance you’ve come to expect from us,” said Ed Bastian, chief executive of Delta, in a statement. “Our recovery effort exemplified the hard work and determination of Delta people worldwide, and all 80,000 remain dedicated to regaining your trust.”

System outage at Delta cost the airline $100 million in revenue [Minneapolis Star-Tribune]

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