United Airlines Names Brett J. Hart Acting CEO

United Airlines (UAL) named an acting CEO on Monday night to replace its chief executive who suffered a heart attack about a month into the job.
 
The company said that general counsel Brett J. Hart had taken over for Oscar Munoz, who went on medical leave.
 
United confirmed that Munoz suffered a heart attack Thursday. The company said it was too soon to know how long he would need to recover.
 
Munoz, 56, became CEO in early September after Jeff Smisek abruptly stepped down amid a federal investigation