[Ans] Which airline is headquartered in dallas, texas?

American Airlines Group, Fort Worth, Texas commercial aviation business and airline holding company

American Airlines, Inc. (AA), commonly referred to as American, is a major American airline. Through the airline's parent company, American Airlines Group, it is publicly traded under NASDAQ. American Airlines is headquartered in Fort Worth, Texas, adjacent to the Dallas/Fort Worth International Airport.

 Web: http://www.aa.com

Envoy Air, Fort Worth, Texas

As a wholly owned subsidiary of American Airlines Group, Envoy offers a direct career path to American, the world's largest airline. Envoy Air Inc. (formerly American Eagle Airlines) is an air carrier headquartered in Irving, Texas, in the Dallas-Fort Worth metroplex.

Piedmont Airlines

Piedmont Airlines was a major airline in the United States which operated from 1948 until it was acquired by and merged into USAir in 1989. 

Express. Wikipedia

Headquarters: Salisbury, MD

CEO: Lyle Hogg

Founder: Richard A. Henson

Hubs: Charlotte Douglas International Airport, Philadelphia International Airport

Parent organization: American Airlines Group

PSA Airlines

PSA Airlines, Inc. is an American regional airline headquartered at Dayton International Airport in Vandalia, Ohio, that flies under the American Eagle brand 

US Airways

US Airways (formerly known as USAir) was a major American airline that ceased to operate independently