Ball, a McKeesport, Pennsylvania, automobile dealer and owner of a controlling interest in Bettis Field near Pittsburgh, won airmail contract route No.

In April of the following year, The Clifford Ball Airline began operating between Pittsburgh, Pennsylvania, and Cleveland, Ohio.

The following August, Ball Airline became the first airline to serve Washington, D.C., from the west, offering its flagship "Path of the Eagle" service from Cleveland to Hoover Field across the Potomac River from Washington, D.C.[6] A "Path of the Eagle" brochure and schedule are displayed at the Pitcairn Field Web site.

[7] Ball sold his interests in November 1930 to Pittsburgh Aviation Industries Corp., and the airline became Pennsylvania Air Lines (PAL).

[16] Early in its existence, PCA faced a minor crisis in January 1937 when the Bureau of Air Commerce temporarily grounded the airline's Boeing 247s.

[20] In September 1943 Pennsylvania Central requested the CAB authorize new routes affecting 23 states indicating plans for a major expansion after the war.

[26] In 1946 PCA began flying the Douglas DC-4 but found the airplane was unprofitable on some of its low volume short segment routes.

One of PCA's DC-4s had been used to transport President Roosevelt to the Casablanca Conference during World War II[27] Ten DC-4s still served Capital at the time of the UAL merger.

[9] By 1946, the combination of expansion and post-war inflation were financially pressing United States airlines.

[34][35] In 1948 Capital introduced the "Nighthawk", one of the first coach class services, to compete with the railroads between Chicago and New York City, as well as the dominant airlines on the route, United, TWA and American.

In 1955 Capital became the first U.S. operator of the British manufactured, four engine Vickers Viscount, the first passenger turboprop airliner.

[37] The Viscount propjets were deployed on the flagship Washington-Chicago route and the airline had planned to fly them on expanded service; however, Capital was mostly stymied by the federal Civil Aeronautics Board (CAB).

He was the captain of Capital Flight 67 which crashed turning final to Tri-City Airport, Freeland, Michigan on April 6, 1958.

On April 1, 1960, the New York State Commission Against Discrimination faulted Capital Airlines for failing to hire Patricia Banks, an African-American woman who had been denied employment as a flight attendant despite meeting all job requirements.

[47][48][49] By 1961 Capital had begun operating its first and only jet aircraft type: new Boeing 720 jetliners leased from United Airlines.

[14] The cover of the airline's June 1, 1961, timetable proclaimed: "New Boeing 720 Jets New York - Atlanta - New Orleans: 2 Round Trips Daily".

[50] This same timetable stated that Capital was operating "596 daily flights" and was also flying: "The Only Jets to Miami from Pittsburgh and Cleveland".

Marshall was transporting a passenger in a Capital Airways Piper PA-31 Navajo from Waterbury to upstate New York.

Many people believe that the passenger, a businessman who was facing both bankruptcy and indictment for fraud, and who had attempted to buy a large life insurance policy just prior to the flight, killed the pilot and himself, causing the crash.

[62][63] In 1937, PCA's main route was from Milwaukee to Washington, D.C., with stops in Muskegon, Grand Rapids, Lansing, Detroit, Cleveland, Akron, and Pittsburgh.

Marie and Traverse City; from Pittsburgh to Erie and Buffalo; and from Charleston to Tri-Cities, Knoxville, Chattanooga, and Birmingham.

[68] By 1960, the year before its merger with United, Capital served Florida with its own aircraft on flights to Jacksonville, Miami, St. Petersburg, Tampa, and West Palm Beach.