http://www.coloradoan.com/article/20110718/UPDATES01/110718001 Frontier Airlines is canceling more flights at Denver International Airport because of hail damage to its airplanes. Spokesman Peter Kowalchuk says 39 flights are canceled Monday. He says another 18 flights will be canceled on Tuesday. The airline says it is helping passengers find travel on other airlines and it's using aircraft from other subsidiaries. Frontier has also rented planes from other carriers. United Airlines canceled 13 more departures from Denver International Airport on Sunday while it inspected airplanes for damage from last week's hailstorm. No information was available on Monday cancellations.