The wing is swept back at 30 degrees and, along with other design features, allows a maximum operating Mach number of 0.86. To reach a long span and high aspect ratio without a large weight penalty, the wing has relatively high Thickness-to-chord ratio of 11.8% or 12.8%. Jet airliners have Thickness-to-chord ratios ranging from 9.4% (MD-11 or Boeing 747) to 13% (Avro RJ or 737 Classic). Each wing also has a tall winglet instead of the wingtip fences found on earlier Airbus aircraft.