sentences:  From Bettis Field and the Allegheny County Airport, to the modern Pittsburgh International Airport (PIT), the city continues to play an important role in the industry and science of flight.According to a book and newspaper story from the 1930s, Gustave Whitehead made a very early motorized flight of about half a mile in Pittsburgh in April or May 1899.Aviation experts debated the topic, and a few decided for Whitehead, while the great majority, such as Charles Harvard Gibbs-Smith, said the flights could not have occurred.