America West was one of the first airlines to use extensive "cross-utilization", in which employees were trained in a variety of airline jobs, such as pilots trained in dispatch, and both baggage handlers and flight attendants being trained as gate agents. America West also started as a "full service" airline, in contrast with Southwest Airlines, the discount air carrier competing in many of the same markets. America West also utilized an aggressive employee stock ownership program, in which new employees were required to invest 20% of their salary in company stock, providing a steady flow of cash as the company grew.

In 1985, America West had grown to the point that no more gate space was available at Sky Harbor International Airport. While the new Terminal 4 at Sky Harbor was approved in 1986, it became apparent that additional gates would be needed before Terminal 4 was completed, and a temporary concourse was added to the southwest corner of the Airport's Terminal 3, adding six gates (eventually a total of 11 gates by 1990) for the use of America West.

The airline's rapid growth continued in 1986, with the airline greatly expanding its fleet, primarily with Boeing 757s purchased from Northwest Airlines after Northwest bought out Republic Airlines, as well as the acquisition of a number of De Havilland Canada Dash 8 aircraft for local service from Phoenix and Las Vegas. Also in 1986, the airline started running red-eye flights from Las Vegas to increase aircraft utilization.

The rapid growth of America West resulted in large operating losses for the airline, and by 1986 the company was on the verge of bankruptcy. Originally slated to occupy the vast majority of the gates in the under-construction Terminal 4, America West had to reduce its commitment to the city of Phoenix to just 28 gates, with the growing Southwest Airlines agreeing to lease the remainder of Terminal 4. In August 1987 a unit of Ansett Transport Industries Ltd. , an Australian airline company and at the time 50% owned by News Corporation, purchased a 21.6 percent stake in America West. Despite revenue problems, America West continued its growth, with a rebuffed attempted buyout of Eastern Air Lines "shuttle" division in 1988.

As 1989 opened the airline explored destinations beyond the United States, America West filed with Department of Transportation for a Phoenix to Sydney route, to connect with now defunct Ansett Airlines. However the proposal was rejected and the Reagan Administration awarded the route to another airline. In 1989, the airline leased four Boeing 747 aircraft (formerly operated by KLM), offering service to Hawaii and Nagoya, Japan, as well as an expansion of service to many Mexican destinations. 

In 1990, the airline moved into the new Terminal 4 and also took the delivery of several Airbus A320 aircraft that were destined for the now-defunct Braniff Airways. The A320s were sold to America West at a steep discount. Braniff had assumed the Airbus A320 order after purchasing the original order rights from Pan Am, another troubled carrier. The United States Department of Transportation classified America West Airlines a major airline.

 Despite these developments, the airline continued to lose money. The operating expenses at the new Terminal 4 were much higher than previous expenses in Terminal 3's temporary concourse. The Nagoya, Japan route was essentially a bust (the planes were flying with almost no passengers), with extremely low ticket sales. Finally, concerns about stability in the Gulf States in the lead-up to the Persian Gulf War lead to increasing fuel costs. This combination forced America West to file for bankruptcy in June 1991.

America West operated in bankruptcy from 1991 to 1994. As part of its restructuring, the employee stock became worthless, the Hawaii and Nagoya routes were scrapped (and the 747s sold), and the airline's fleet was heavily pared down to 87 aircraft. All of the Dash 8 aircraft were sold, and America West's service to local markets was contracted to Mesa Airlines, which began conducting operations as "America West Express."

The bankruptcy forced a number of changes on the management side as well. Founder and CEO Ed Beauvais was removed as CEO, but remained on the board of directors, while Mike Conway, who had been with the airline since its start, was appointed as the new CEO, although he in turn would leave the airline in 1994, replaced by A. Maurice Myers. America West's Flight Attendants also unionized in 1993, a move which ended the cross-utilization between customer service agents, flight attendants, and ground agents. Many maintenance and training functions that were previously operated by America West in-house were also outsourced during the bankruptcy.

Finally, in 1994 America West managed to secure a reorganization that allowed it to come out of bankruptcy, with a large portion of the airline owned by a partnership including Mesa Airlines and Continental Airlines, which resulted in code-sharing agreements with these airlines.

To help reinvigorate the airline as it emerged from bankruptcy, a number of consumer-visible changes occurred, including a new color scheme and logo (used until the merger with US Airways), new livery, E-ticket, and online ticket purchasing (in 1996). The airline continued ordering Airbus A320 aircraft, and gradually started retiring its older Boeing 737-200 aircraft.

In the 1990s, America West Airlines opened an east coast hub at Port Columbus International Airport in Columbus, Ohio. Chautauqua Airlines was used to provide commuter and regional flights. An America West Club was provided for the hub.

At the end of 2001, America West Airlines received a loan of $380 million from the Air Transportation Stabilization Board. As of April 2005, the remaining balance on the loan was $300 million. On October 19, 2005, the loan was repaid when the debt was refinanced with other lenders. In February 2003, America West Airlines announced plans to close the Port Columbus International Airport hub. The closure was completed later that year reducing the number of scheduled flights from near 50 a day to only 4. America West Airlines, in conjunction with SkyMedia International, pioneered advertising space inside the cabin of the aircraft as an additional revenue source to help bring costs down. The companies developed FAA approved tray-table advertising.