United canceling flights after hail damage

United employees inspect a plane for hail damage

DENVER, Colorado (CNN) -- United Airlines was doing damage control Friday after a storm swept through Denver a day earlier, dropping golf-ball-size hail that damaged 32 United jets and forced the cancellation of more than 100 flights.

United spokesman Chris Brathwaite said the airline is doing "everything we can to limit the disruption to our customers." Dozens of flights were canceled Friday morning.

Brathwaite said some of the planes will be out of service for a month.

Though it is not unusual for planes to be damaged during hailstorms, "I don't know if it's happened on this level before," he said. "We're kind of at Mother Nature's whim when it comes to these kind of things."

To minimize cancellations, United has pulled spare aircraft from hangars and put them into service, he said. He did not specify how many spare aircraft had been activated.

But he noted that the 32 damaged planes is just a small part of United's fleet of more than 600 planes.

"For the most part, people traveling on United, the overwhelming majority, will not notice anything different," he said.

United canceled about 125 flights Thursday due to the damage. Since a typical jet flies at least four legs per day, the cancellations affected cities other than Denver, he said.