Pilot Shortage Forces United to Cancel 150 Flights at O’Hare

United Airlines canceled at least 150 flights Saturday at O’Hare International Airport, mostly because of a shortage of pilots.

Some of the airline’s workers called in sick, but many of the missing pilots had already worked all their allotted weekly hours trying to make up for flights canceled Thursday and Friday because of bad weather in the East, Chris Brathwaite, a United spokesman, said.

United pilots have refused to work overtime since their contract expired in April, Brathwaite said.

The company and the pilots’ union are negotiating a contract with a federal mediator and hope to have an agreement by early September.

A pilots’ union spokesman did not immediately return a call Saturday seeking comment.

In the past, the union has denied having any organized effort to refuse overtime shifts.

United has about 960 flights per day out of O’Hare.