US Airways reservations to transition to American

American Airlines will begin transferring US Airways passenger reservations to its own system this summer, with the goal of phasing out the US Airways brand by the end of the year.

American, which merged with US Airways in December 2013, notified travel agents and online ticket sites Tuesday that it would begin the transition as early as July, with the final "operational cutover" 90 days later, in October, when flights with the US Airways brand will end.

Getting to a single reservation system is one of the most complex steps in the merger that created the world's largest airline with 100,000 employees and 6,700 daily flights.

"It's a complex and harried process to make it all work seamlessly," said Maya Leibman, American's chief information officer. "Ideally what happens at the end of this, our customers say, 'What integration?' They had no idea that anything actually happened."

For now and 90 days after the transfer begins, US Airways customers will still be on US Airways-coded flights.

Then, in October, the flights will technically become American flights. Departure times and flight schedules will remain the same. Only the letter code on the reservation will change: AA instead of US.

Travelers who book now for the holidays and beyond can still go to usairways.com.

Starting in October, fliers with future reservations will get an e-mail alert that their US Airways flight has been rebranded AA. For example, what has been US5227 to Dayton, Ohio, will become AA5227 to Dayton.

Passengers booking flights in October and beyond will be redirected to the American website aa.com. The US Airways website will eventually disappear.

In October, US Airways airport check-in kiosks and ticket counters will be renamed "American." It won't be until late 2016 that all 600-plus US Airways planes will be repainted with the American logo and colors. Thus for some time to come, the flights will be technically American, but the planes will say US Airways.

Philadelphia is a hub for US Airways and American, and 73 percent of airport travelers here fly on the combined carrier.

American said in a letter to travel agents Tuesday that it is taking a phased-in approach, rather than an overnight switch from US Airways to American.

Kerry Philipovitch, American senior vice president of customer experience, said 9,000 US Airways airport employees will be trained in the new technology this summer, and 2,000 US Airways reservation agents will get six weeks of training.

"We want it to be like a swan, where we are all paddling beneath the water, but the consumer just glides smoothly across the pond," Philipovitch said on a call with reporters.

In previous airline mergers, technical glitches emerged in linking the reservation systems.

American CEO Doug Parker, the former chief executive of US Airways, "has been pounding the message of not being complacent," Leibman said. "We have to be totally paranoid and totally worried about every single thing that could possibly go wrong."

To complete merging the airlines, the flight operating system has to be combined: pilot and flight crew systems, flight movement and dispatch, tech ops, maintenance, and engineering. These operational changes should be invisible to consumers, "but it's a big chunk of integration work," Leibman said. "That will happen throughout 2016 and 2017."