The merger between American and US Airways has been going on for about two years now. So far we’ve seen the airlines merge their frequent flyer programs and get on a single FAA operating certificate.
The last major step in the integration between American and US Airways is combining reservations systems, which is scheduled to happen on October 17, 2015. When this happens, US Airways will officially cease to exist, as all flights operated by the “new” American will have American flight numbers.

To commemorate the history of US Airways, there will be a special flight on October 16, 2015, which will officially be the last US Airways flight.
US Airways’ predecessor (All American Aviation) was founded in 1939, so to celebrate US Airways will have flight US1939 on October 16, 2015.
The flight (which will be operated by a US Airways Airbus A321) will have the following routing:
10/16 US1939 Philadelphia to Charlotte departing 10:05AM arriving 12:04PM
10/16 US1939 Charlotte to Phoenix departing 2:35PM arriving 4:01PM
10/16 US1939 Phoenix to San Francisco departing 5:10PM arriving 7:12PM
10/16 US1939 San Francisco to Philadelphia departing 9:55PM arriving 6:18AM (+1 day)

Via TheStreet, it looks like festivities are planned at all stops along the way, and former US Airways CEO Ed Colodny will also be on the final flight:
Passengers on the last flight will include former US Air CEO Ed Colodny.
“It’s the end of the name, not the end of the airline as such, but the end of the name, and I just thought it would be neat to fly on the last flight,” Colodny said in an interview. “It’s for nostalgia.”
At each of the four stops as well as on the final flight, American plans celebratory events, Thomas said.
I’d be surprised if Doug Parker weren’t on it as well.
San Francisco seems like an odd choice given that it’s a United hub and not a US Airways hub, though there’s an explanation for that:
American spokeswoman Martha Thomas said the flight was selected to be the last one after the Oct. 16 and Oct. 17 schedules at US Airways hubs were pared down in order to assure that employees would have sufficient time to focus on the cutover from Shares to Sabre reservations systems.
So that’s actually, officially the last US Airways flight based on how the schedule worked out.
If you do want to book US1939, space is wide open on all segments. For the flights from Philadelphia to Charlotte to Phoenix to San Francisco, there are even plenty of first class seats for sale. That being said, for the last flight from San Francisco to Philadelphia, first class is sold out, though economy is still for sale.
At $767 one-way for economy, it’s sort of an outrageous fare, though (for what it’s worth, it doesn’t seem specific to the last flight, but rather all fares between San Francisco and Philadelphia that day). I assume you can lower the fare by originating or terminating in different cities, though.

Kudos to them for planning this commemorative flight. It’s great to honor an airline with such a legacy.
Does anyone plan on booking one of these commemorative US Airways flights?
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