Three Democratic senators pressed Delta Air Lines CEO Ed Bastian to answer questions about the airline's planned use of artificial intelligence to set ticket prices, raising concerns about the impact on travelers.

Last year, Delta Air Lines announced it was testing out dynamic pricing on some flights using tools built by the tech company Fetcherr. And while the test was initially limited, executives from the company announced that 3% of flights now use AI pricing, and they hope to sell 20% of all tickets using a dynamic price by the end of the year.