A global economy that depends on air freight for the swift movement of goods was challenged this past year as governments across the world tightened security to counter terrorism. Air and express carriers were forced to scramble to meet shipper demands for quick, reliable deliveries while complying with new security restrictions.

This year, six aircargo carriers met that challenge and soared above the crowd. Three of those airlines—Southwest Airlines, Korean Airlines and Lufthansa Cargo—had made the Readers' Choice list last year. They were joined this year by newcomers Singapore Airlines, Air Canada and Air France. Those six carriers earned higher grades than the average customer satisfaction score of 31.23.

Overall, logistics managers this year graded air carrier performance higher than they had in the past in two of the five categories measured. The number for on-time performance climbed to 10.26 from last year's 10.13. The grade for information technology also gained altitude, rising to 4.20 from 3.83.

Air carriers encountered turbulence when readers went to grade them in three other categories, however. The value score dipped to 7.35 from 7.47, customer service slid to 6.10 from 6.29, and equipment and operations inched down to 3.32 from 3.38. Still, the composite customer satisfaction score of 31.23 was slightly higher than last year's 31.09.

As for air express carriers, the same three companies that emerged as winners last year soared aloft once again. FedEx Express, United Parcel Service and DHL Worldwide Express all exceeded readers' expectations and earned quality honors. The marks for those three were higher than the composite customer satisfaction score of 33.31, which itself was a notch above last year's benchmark of 33.24.

As a group, though, air express carriers earned higher marks than they did last year in only one category, information technology. Survey respondents graded the carriers' information technology capabilities at 4.65 compared to 4.20 last year.

Marks fell in the other four categories measured. On-time performance slipped to 10.83 from 10.87; the value rating dipped to 7.86 from 7.92; customer service dropped to 6.34 from 6.61; and equipment and operations slid to 3.62 from 3.64.