It's been almost exactly two years since US Airways bought America West and, as of Wednesday, the two airlines officially completed their merger, having been granted one operating certificate by the Federal Aviation Administration. The merger involved integrating the airlines' separate information technology systems and flight operations computer systems, airport, maintenance and on-board policies and procedures. Beginning this week, all operations will be under the US Airways flag. The merged carrier said the next step is to achieve single contracts with pilots, flight attendants and ground and maintenance employees. Visit [www.usairways.com].