Gary Leff, co-founder of the frequent flier community Milepoint.com, says the new program probably will blend aspects of the two existing ones, each of which has its pluses.
American, for instance, gives one-way award tickets for half the miles required for a round trip, a perk that US Airways doesn't offer, Leff says. US Airways, meanwhile, has low-price awards to many tourist hot spots and unlimited free upgrades for elite fliers; American doesn't.
Diluting either benefit carries risks. Fliers often grow attached to perks that fade when airlines combine. For instance, American Express Platinum and Black card holders used to have automatic access to Continental lounges. They lost that privilege after the merger with United.
Frequent flier George Fiscus, who has racked up hundreds of thousands of miles flying US Airways, appreciates the automatic upgrades to first class and doesn't want to lose them.
"As someone who typically flies over 100,000 miles a year, the only perk of that experience is the more comfortable ride," Fiscus says. "If they take that option away or make it more difficult to upgrade, it will be very disappointing after years of loyalty."
Quick action expected
If the deal is approved, passengers should see US Airways and American housed together at most airports sooner rather than later. "That one tends to get resolved very quickly," Kirby says.
John Thomas, head of the global aviation and travel practice at L.E.K. Consulting, says passengers also should see coordinated flight schedules quickly. "One of the first things that happens is harmonization of the schedules and fleet," he says.
American and US Airways mirror each other on only 17 non-stop routes.
With so little overlap, the airlines' leaders say they plan to hold onto both carrier's hubs and expand service rather than dramatically slash flights to certain markets -- a plus, they argue, in getting government approval for the merger.
But Thomas suspects US Airways' hub in Philadelphia could be vulnerable, given its proximity to New York's JFK, a major portal for American's trans-Atlantic service. Other industry watchers wonder whether the US Airways hub in Phoenix may lose some service to American's bigger international gateway in Dallas.
Losing some service out of Phoenix wouldn't sit well with Sue Hershkowitz-Coore of Scottsdale, Ariz., a frequent, high-status flier on both carriers. It was US Airways' non-stop service out of Phoenix that enticed her to shift some of her business from American in the first place.
"I was an American devotee until US Airways came into Phoenix," she says. "It's just so pleasant to take one flight instead of connecting through Dallas."
A change is gonna come
It's likely some aircraft will change. American has been under bankruptcy protection since November 2011, which allows for contracts for new planes to be altered or even canceled.
"Anything they can change before the airline comes out of bankruptcy, they will," analyst Hegeman says.
For instance, American has ordered Airbus A319's, but Hegeman says that order might be modified, because US Airways prefers bigger aircraft such as the A321.
Whatever planes the new airline flies, pilots won't have to worry about learning to fly each other's jets immediately, union officials say.
"For the short term, pilots for US Airways will continue to fly their aircraft and American pilots will continue to fly American's aircraft," says James Ray, spokesman for the US Airline Pilots Association, which represents US Airways pilots.
Such protections are put in place to keep pilots from slipping to the back of the line in terms of pay, perks and schedule. For instance, US Airways doesn't currently fly the 777, but American does, and there may be a set period in which American pilots continue to fly that plane exclusively. Likewise, US Airways flies A330's, while American does not.
"This has been practiced in other mergers," Ray says. "They don't want a more senior group going over and bumping ( a more junior group) off the airplanes."
But, Ray says, "Eventually, we will meld these two groups into one pilot group, and we'll all be on one seniority list."
As jet-fuel prices soar and Delta battles to lift itself from bankruptcy protection, members who cherish their SkyMiles have a lot of worries.
One thing is certain for the airline industry next year: There will be fewer flights.