A new ranking of full-service airlines puts a Gulf carrier in the top spot for the first time. Airline Ratings bestows the honor on the carrier Etihad, based in Abu Dhabi in the United Arab Emirates. The ranking takes into account factors including the number of flights, serious incidents, international safety audits, pilot training, and—new this year—incidents of turbulence. No American carrier cracks the top 10, with Alaska Airlines the top US finisher at No. 15. Delta (23) and American (24) were the only other finishers in the top 25. Here are the top 10: