Crown reinforcement of an aircraft tire with improved mechanical strength in order to increase the burst pressure of the tire, during a standard pressure test. An aircraft tire comprises a working reinforcement made up of a strip (5) wound continuously in a zigzag, from a starting end (51) to an ending end (52), in a circumferential direction (XX) of the tire, along a periodic curve (7) forming a non-zero angle A with the circumferential direction (XX) of the tire and in an equatorial plane (XZ) of the tire. The starting end (51) and the ending end (52) of the strip (5) are positioned axially at a distance (DI, DF) at most equal to 0.25 times the axial width W.sub.T of the working reinforcement from an axial end (E1, E2) of the working reinforcement.

The strip-winding method, includes: a first step of supplying a strip to a wound body including an inclined part; and a second step of moving a winding roller along an outer circumferential surface of the wound body within one plane, the winding roller being capable of pressing the strip on the wound body, and of winding the strip on the outer circumferential surface of the wound body. In the second step, the roller inclination angle of the rotational axis line of the winding roller with respect to the one plane is changed, and the roller inclination angle at the time the strip is wound around the inclined part is set to be greater than the roller inclination angle at the time the strip is wound around a maximum diameter position of the wound body.

A method of manufacturing a pneumatic tire has a winding step of forming a rubber ribbon winding body constructing a tread rubber by spirally winding a rubber ribbon obtained by co-extruding a first rubber and a second rubber which are different in hardness. The first rubber is mainly arranged in a first area by making a cross sectional area ratio of the first rubber greater than that of the second rubber. The second rubber is mainly arranged in a second area by making the cross sectional area ratio of the first rubber smaller than that of the second rubber. The cross sectional area ratio of the first rubber becomes progressively smaller in a part of the first area as the second area approaches. The rubber ribbon retains an interface boundary between the first rubber and the second rubber to at least a part of the second area.

A method of forming a belt structure for a tire includes providing a drum having a center section. A first drum edge is near a first edge of the center section and a second drum edge is near a second edge of the center section. A first end surface extends from the center section first edge to the drum first edge and a second end surface extends from the center section second edge to the drum second edge, and a radius of each end surface is smaller than the center section radius. A rubber strip reinforced by a plurality of cords includes an outer edge and an inner edge. The strip is wound about the drum, turning from a first winding angle to a second winding angle on an end surface to reduce the tension and length differential between cords at the outer edge and inner edge of the strip.

Working reinforcement (2) of an aircraft tire, made by the zigzag winding of a strip (5) having width W, with a periodic curve (7), corresponding to the mid-line of the strip, forming, with the circumferential direction (XX), a non-zero angle A. The circumferential distance (c) between the extrema (S.sub.51, S.sub.52, S.sub.53) of the respective mid-lines of two consecutive strip portions (51, 52, 53) is equal to the ratio W/sin A. For any set of three consecutive strip portions (51, 52, 53), made up of a first, a second and a third portion, the respective mid-lines of the first and third strip portions (51, 53) intersect at an intersection point (I), axially aligned with the extremum (S.sub.52) of the mid-line of the second strip portion (52) and axially on the inside of said extremum (S.sub.52) at an axial distance (a) at least equal to the width W.

In a method of manufacturing a pneumatic tire, a placement unit is moved relative to a forming drum in a drum circumferential direction to repeatedly perform a one-side step of delivering a reinforcing wire in a folded back state in a length from a central portion toward one side in the width direction of the forming drum and compression bonding the reinforcing wire to an innerliner of an outer surface of the forming drum, and after delivering the reinforcing wire in the length toward the one side in the width direction as described above, perform an other-side step of delivering the reinforcing wire in a folded back state in a length from the central portion toward an other side in the width direction of the forming drum and compression bonding the reinforcing wire to an outer surface of the innerliner.

Aeroplane tire (1) comprises a working reinforcement (2) radially between tread (3) and carcass reinforcement (4). Working reinforcement (2) includes a working biply (21) comprised of the zigzag circumferential winding of strip (5) of width W onto a cylindrical laying surface (6) of radius R, with its axis of revolution being axis of rotation (YY) of the tire, in a periodic curve (7) with period P and forming angle A with circumferential direction (XX) of the tire in equatorial plane (XZ) of the tire. The winding of strip (5) comprises N periods P of curve (7) over T circumferences 2R of surface (6). N is a whole number which satisfies the following conditions: (a) N*(W/sin A)=2R, (b) N*P=2R*T, where T is a whole number, (c) N*T is the lowest common multiple of N and T,
and the ratio T/N is at least equal to 1.8 and at most equal to 2.2.

A tire comprises a sealing layer comprising a junction (21) extending in a main direction (D4) forming, with the circumferential direction (Z) of the tire: in a portion (15S) of the sealing layer extending axially in radial line with the working layer, an angle (ES) ranging, in absolute value, from 20 to 60, and in a portion (15F) of the sealing layer extending radially in each sidewall, an angle (EF), in absolute value, strictly greater than the angle (ES) of the main direction (D4) of the junction (21) in the portion (15S) of the sealing layer extending axially in radial line with the working layer.