A grounded Boeing 787 Dreamliner jet operated by United Airlines is parked at Los Angeles International Airport (LAX) on January 17, 2013. (David McNew/Getty Images)
CHICAGO (AP) - United Airlines says it expects to start flying its Boeing 787s again on May 20.
The 787s had been grounded because of concerns about smoldering batteries, but they have been returning to the skies. Ethiopian Airlines was the first to fly a 787 again, on April 27.
The first United flight will be from Houston to Chicago. A spokeswoman for United Continental Holdings Inc. says the first flights will be around the U.S.
Boeing is putting a new battery system on 50 of the 787s that have been delivered around the world. United's planes are being worked on at a Boeing facility in San Antonio, Texas.