Figure 7-10.--Sectional view of aircraft tire showing construction details.
Tread Patterns
arrangement provides a strong and flexible tire that
distributes impact shocks over a wide area. The
There are three tread patterns or tread designs used
functions of the cord body are to give the tire tensile
on naval aircraft. They are plain, ribbed, and nonskid. A
strength, to resist internal pressures, and to maintain
plain tread has a smooth, uninterrupted surface. A
tire shape.
ribbed tread has three or more continuous
The tread is a layer of rubber on the outer surface of
circumferential ribs separated by grooves. A nonskid
the tire. It protects the cord body from abrasion, cuts,
tread is any grooved or ribbed tread. Other tread
bruises, and moisture. It is the surface that contacts the
designs may be provided under specific circumstances
ground.
or as required by applicable MS standards or drawing.
The most common design used on naval aircraft is the
The sidewall is an outer layer of rubber adjoining
ribbed pattern.
the tread and extending to the beads. Like the tread, it
protects the cord body from abrasion, cuts, bruises, and
Tread Construction
moisture.
The beads are multiple strands of high-tensile
The tread construction will usually be one of four
strength steel wire imbedded in rubber and wrapped in
types. Other tread types may be necessary for specific
strips of open weave fabric. The beads hold the tire
circumstances or as required by military standards,
firmly on the rims and serve as an anchor for the fabric
such as ice and snow treads.
plies that are turned up around the bead wires.
NOTE: Additional safety precautions are required
The chafing strips are one or more plies of
in handling ice and snow treads.
rubber-impregnated woven fabric wrapped around the
Rubber tread. A rubber tread is constructed from
outside of the beads. They provide additional rigidity to
100-percent new (no reclaim) rubber. It may be new
the bead and prevent the metal wheel rim from chafing
natural rubber, new synthetic material, or a blend of
the tire. Tubeless tires have an additional ply of rubber
new material and new synthetic materials.
over the chafing strips to function as an air seal.
Cut-resistant tread. A cut-resistant tread has
The breakers are one or more plies of cord or
woven fabric impregnated with rubber. They are used
improved cut-resistant properties that are imparted to
between the tread rubber and the cord body to provide
the tire by incorporating a barrier into the undertread
extra reinforcement to prevent bruise damage to the
that resists penetration of cutting objects.
tire. Breakers are not part of the cord body.
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