As United and Continental continue to combine their operations, the latest casualty will be 688 flight attendants at United who will be furloughed in April despite a hiring push for the same position at Continental, which hired 485 last year.
The action stems from the inability of United and its union to agree on a unified contract for the combined airline.
"We have offered opportunities to flight attendants for both voluntary furloughs and job-sharing programs in order to mitigate involuntary furloughs, but these programs did not generate enough volunteers and we are faced with the difficult step of furloughing 688 flight attendants," United spokeswoman Megan McCarthy said Thursday in an email to CNBC.
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"We are disappointed that on three occasions the subsidiary United AFA rejected a voluntary crossover program that would have provided flying opportunities to hundreds of flight attendants that may otherwise be involuntarily furloughed," she said.