Aircraft radial tire

A pneumatic tire comprising:

• a carcass;
• a belt reinforcing structure comprising a plurality of belt layers that include at least one spiral belt layer and at least one zigzag belt layer, each of the at least one spiral belt layers having cords arranged at an angle of 5° or less with respect to an equatorial plane of the pneumatic tire and each of the at least one zigzag belt layers having cords arranged at an angle of 5° to 40° with respect to the equatorial plane and extending in alternation to turnaround points at each lateral edge of the belt reinforcing structure,
• wherein a first belt layer of the plurality of belt layers located radially outward of the carcass is one of the at least one spiral belt layer, and
• wherein the first belt has a belt width less than a widest belt layer of the plurality of belt layers;
• and
• a tread comprising two or more main grooves extending circumferentially continuously around the pneumatic tire and defining a plurality of ribs that include two axially outermost ribs,
• wherein, at 10% to 100% of a rated pressure and no load, each of the two axially outermost ribs are raised in relation to a respective next nearest rib located axially inward of the respective axially outermost rib by a gap E,
• wherein, the gap E is the distance between a line L1 that is parallel to a line L2, the line L1 is defined as a line extending between points A and C that located an equidistance along the next nearest rib surface from a midpoint B of the next nearest rib surface, wherein the points A and C are each 0.5 cm to 5 cm from the midpoint B, the line L2 is defined as a line parallel to the line L1 and passing through a point D that is at a most radially outward point along a surface of the axially outermost rib, and the gap E is 1 mm to 7 mm.