Tire comprising major grooves with a depth at least equal to 4 mm and with a width at least equal to 1 mm. The radially outermost working layer (41) comprises at least one undulation (412). The undulation (412) is such that the undulation (412) portion of the working layer (41) represents at least 10% of the surface of the working layer (41), has an amplitude of at least 1 mm and is radially on the outside of the points of the working layer (41) that are in line with the bottom face (243) of the major groove (24) closest (412). All the layers of material (3, 6, 7) making up the radial stack of the crown structure (S) have mean surfaces parallel to that of the radially outermost working layer (41).

Tire comprising major grooves with a depth at least equal to 4 mm and with a width at least equal to 1 mm. The radially outermost working layer (41) comprises at least one undulation (412). The undulation (412) is such that the undulation (412) portion of the working layer (41) represents at least 10% of the surface of the working layer (41), has an amplitude of at least 1 mm and is radially on the outside of the points of the working layer (41) that are in line with the bottom face (243) of the major groove (24) closest (412). All the layers of material (3, 6, 7) making up the radial stack of the crown structure (S) have mean surfaces parallel to that of the radially outermost working layer (41).

The pneumatic tire includes: a pair of bead portions; a pair of sidewall portions; a tread portion; a carcass; a reinforcing rubber layer, a tire widthwise cross-section of the reinforcing rubber layer having a substantially crescent shape; an inclined belt including at least one inclined belt layer formed by a plurality of cords extending at an inclination to a tire circumferential direction and covered with rubber; and an inner liner provided on an inner peripheral surface of a tire body in at least the tread portion. In a tire widthwise cross-sectional view, an edge of the inner liner is positioned farther outward in the tire radial direction than a tire maximum width position of the pneumatic tire and farther inward in the tire radial direction than a perpendicular from a tire widthwise edge of the inclined belt to the inner peripheral surface of the tire body.

A heavy-duty pneumatic tire includes a section width being equal to or less than 335 mm, an aspect ratio being equal to or less than 55%, and a toroidal carcass extending between axially spaced bead portions through a tread portion and sidewall portions. The carcass includes a carcass ply which includes a main portion and a turn-up portion turned up around a bead core of each bead portion. A belt layer is disposed radially outward of the carcass in the tread portion, wherein a radially outer end of the turn-up portion is located between the main portion and the belt layer in the tread portion. A sheeted rubber layer is disposed between the main portion and the turn-up portions in each sidewall portion.

A heavy-duty pneumatic tire includes a section width being equal to or less than 335 mm, an aspect ratio being equal to or less than 55%, and a toroidal carcass extending between axially spaced bead portions through a tread portion and sidewall portions. The carcass includes a carcass ply which includes a main portion and a turn-up portion turned up around a bead core of each bead portion. A belt layer is disposed radially outward of the carcass in the tread portion, wherein a radially outer end of the turn-up portion is located between the main portion and the belt layer in the tread portion. A sheeted rubber layer is disposed between the main portion and the turn-up portions in each sidewall portion.

The present invention aims to provide a pneumatic tire with sufficiently reduced rolling resistance. The pneumatic tire according to the present invention including a carcass having a carcass main portion extending from a tread portion via a sidewall portion to a bead portion in a toroidal shape and locked on a bead core embedded in the bead portion, and a belt disposed on a crown portion outer peripheral side of the carcass, characterized in that, when mounted on an applicable rim and put under a predetermined internal pressure no-load condition, a minimum value R1 of a curvature radius of a tire width direction cross-section in a tire radial direction outer portion of the carcass main portion positioned on an tire radial direction outer side than a position where a distance measured from a tire radial direction inner end of the carcass outwardly in the tire radial direction becomes ½ of a carcass cross-sectional height is 0.6 times or less of a minimum value R2 of the curvature radius of the tire width direction cross-section of a portion that, in the tire radial direction inner portion of the carcass main portion positioned on the tire radial direction inner side than the tire radial direction outer portion, bulges out in the tire width direction.

The present invention aims to provide a pneumatic tire with sufficiently reduced rolling resistance. The pneumatic tire according to the present invention including a carcass having a carcass main portion extending from a tread portion via a sidewall portion to a bead portion in a toroidal shape and locked on a bead core embedded in the bead portion, and a belt disposed on a crown portion outer peripheral side of the carcass, characterized in that, when mounted on an applicable rim and put under a predetermined internal pressure no-load condition, a minimum value R1 of a curvature radius of a tire width direction cross-section in a tire radial direction outer portion of the carcass main portion positioned on an tire radial direction outer side than a position where a distance measured from a tire radial direction inner end of the carcass outwardly in the tire radial direction becomes ½ of a carcass cross-sectional height is 0.6 times or less of a minimum value R2 of the curvature radius of the tire width direction cross-section of a portion that, in the tire radial direction inner portion of the carcass main portion positioned on the tire radial direction inner side than the tire radial direction outer portion, bulges out in the tire width direction.

A radial tire for an aircraft, the radial tire having a rim diameter of 20 inches or less includes a pair of bead portions; a pair of sidewall portions extending outward from the bead portions in a substantially radial direction; a tread portion that couples together respective radial outer ends of the sidewall portions; a toroidal carcass layer reinforcing a portion between bead cores embedded in the bead portions; a belt layer and a tread that are sequentially laminated on an outer side of the carcass layer in the radial direction, wherein a value M obtained by dividing a tire external diameter D by a distance L between bead heels of the bead portions is in a range of from 4.1 to 5.4.

A heavy-duty tire includes a tread portion including a crown land portion, a shoulder land portion with a tread edge and a middle land portion disposed therebetween. In a tire cross-section of a 5% inflated state, the tread portion comprises a surface profile which comprises an inner arc portion having a radius (R1) of curvature with a center located in a tire equatorial plane and an outer arc portion having a radius (R2) of curvature smaller than the radius (R1) of curvature of the inner arc portion and intersecting the inner arc portion at an inflection point (P). The inflection point (P) is located on the middle land portion, wherein a distance (Lp) in the tire axial direction from the tire equatorial plane to the inflection point (P) is in a range of from 0.35 to 0.50 times a tread half-width (Wt).

A heavy-duty tire includes a tread portion including a crown land portion, a shoulder land portion with a tread edge and a middle land portion disposed therebetween. In a tire cross-section of a 5% inflated state, the tread portion comprises a surface profile which comprises an inner arc portion having a radius (R1) of curvature with a center located in a tire equatorial plane and an outer arc portion having a radius (R2) of curvature smaller than the radius (R1) of curvature of the inner arc portion and intersecting the inner arc portion at an inflection point (P). The inflection point (P) is located on the middle land portion, wherein a distance (Lp) in the tire axial direction from the tire equatorial plane to the inflection point (P) is in a range of from 0.35 to 0.50 times a tread half-width (Wt).