April 8, 2019 -- Delta Air Lines is No. 1, and JetBlue is No. 2, according to the 29th annual Airline Quality Rating (AQR), released today, Monday, April 8. The AQR is the most comprehensive study of performance and quality of the largest airlines in the United States. The rating is a multifactor examination of the airlines based on mishandled baggage, consumer complaints, on-time performance and involuntary denied boardings.