Click to view a short video about Treadcutting. 300K ASF Windows 204K MOV
		Click to view a short video about Typical Wear. 604K ASF Windows 392K MOV

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UNEVEN WEAR
If tread wear is excessive on one side, the tire can be demounted and turned around, providing there is no exposed fabric. Gear misalignment causing this condition should be corrected.

WARNING
Do not probe cracks, cuts or embedded foreign objects while tire is inflated.

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TREAD CUTS
Inspect tread for cuts and other foreign object damage and mark with crayon or chalk. Follow the removal criteria below:

1. Any cuts where fabric can be seen without spreading the cut.
2. Cuts extending more than half of the width of a rib and being deeper than 50% of the remaining groove depth.

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SIDEWALL DAMAGE
Remove tire from service if weatherchecking, cracking, cuts and snags extend down to the casing ply in the sidewall and bead areas. Cuts and cracks deeper than one ply require the tire to be scrapped.

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BULGES
Bulges in any part of tire tread, sidewall or bead area indicate a separation or damaged tire. Mark with crayon and remove from service immediately.

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FABRIC FRAYING/GROOVE CRACKING
Tires should be removed from service if groove cracking exposes fabric or if cracking undercuts tread ribs.

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FLAT SPOTS
Generally speaking, tires need not be removed because of flat spots due to touchdown and breaking or hydroplaning skids unless fabric is exposed. If objectionable unbalance results, however, rebalance the assembly or remove the tire from service.

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BEADS
Inspect bead areas next to wheel flanges for damage due to excessive heat, especially if brake drag or severe braking has been reported during taxi, take-off or landing. If damaged, remove tire from service.

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TIRE CLEARANCE
Look for marks on tires, gear, and in wheel wells that might indicate rubbing due to inadequate clearance.

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WHEELS
Check wheels for damage. Wheels that are cracked or damaged should be taken out of service for repair or replacement in accordance with manufacturer's instructions.

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INFLATION PRESSURE LOSS IN TIRE/WHEEL ASSEMBLIES
Refer to section on MOUNTING for a complete review of these procedures.

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AIRCRAFT TIRE CONDUCTIVITY
Under certain circumstances (for example during refueling), operators have concerns relative to the dissipation of static electricity for aircraft.

In those situations where buildup of static electricity is of concern, it is important that mechanical means always be used to ground the aircraft.

CAUTION!
Do not rely on tires to dissipate static electricity.

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TIRE AND TUBE STORAGE
Ideally, both new and retreaded tires should be stored in a cool, dry place out of direct sunlight. Temperatures should be between 32 degrees F (0 degrees C) and 85 degrees F (30 degrees C). Particular care should be taken to store tires away from fluorescent lights, electric motors, battery chargers, electric welding equipment, electric generators and similar equipment. These items create ozone, which has a deteriorating effect on rubber.

Care should be taken that tires do not come in contact with oil, gasoline, jet fuel, hydraulic fluids or similar hydrocarbons. Rubber is attacked by these in varying degrees. Be particularly careful not to stand or lay tires on floors that are covered with these contaminants.

All tires and tubes should be inspected immediately upon receipt for shipping and handling damage.

Whenever possible, tires should be stored vertically on tire racks. The surface of the tire rack against which the weight of the tire rests should be flat and wide to minimize distortion. Stacking of most tires is permissible; however, care must be used to prevent distortion of the tires on the bottom of the stack. To prevent chine distortion, stacking chine/water deflector tires is not recommended. Tires stored in racks, but leaning on the chine, can also cause distortion. The following is the maximum recommended stacking height:

Tubes should be stored in their original cartons whenever possible. If stored without their cartons, they should be lightly lubricated with talc powder and wrapped in heavy paper.

Tubes can also be stored in matching tires. Tires should be clean and lightly lubricated with talcum powder with tubes inflated just enough to round them out.

Under no circumstances should tubes be hung over nails, pegs or any object that might form a crease in the tube. Such a crease will eventually produce a crack in the rubber.

Tires mounted on wheels should not be stored at service inflation pressures, as this could have a detrimental effect on the condition of the sidewall and tread. If mounted tires are to be stored for long periods, for instance as line station spares, the storage pressure should be a maximum of 50 PSI. Before installation on an aircraft, the inflation should be raised to the specified operating pressure.

For mounted tires that have been stored for an extended period, it would be advisable to repeat the 24 hour diffusion test.

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TIRE AND TUBE AGE LIMIT
Goodyear aircraft tires or tubes may be placed or remain in service regardless of the calendar age, provided all inspection criteria for service/storage or individual customer-imposed restrictions are met.

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RETREAD TIRES
Most military, general aviation and commercial airline tires are designed to be retreaded. Retreading an existing casing can provide more landings per tire at a lower cost per tread giving a significantly lower overall operating cost .

As with new tires, retreads must pass airworthiness authority testing requirements. Inspection techniques, such as air injection, holography and shearography, ensure that used casings and the final retread meet all specifications. Again, as with new tires, retread materials and components are certified by quality assurance standards.

The following is a scenario of the retread process:

Tires are received and assigned a process card and number that follows the tire throughout the complete process. All pertinent information is entered into a computer database.
Tires are visually inspected and air needle pressure tested to reveal any separations or possible liner leaks.
Tires are put into hot storage to shrink the nylon casing back to its original shape.
Tires are then placed on a buffing machine with the casing under pressure to ensure roundness.
The old tread is buffed off the casing along with any removable fabric reinforcement plies.
New fabric reinforcement plies are applied, as required, along with the new tread rubber.
Tires are then placed in a mold and the new tread materials are vulcanized (cured).
Final inspection is made, and each tire receives an FAA approved remanufactured tag.

Along with the standard visual and air needling inspections, a major part of the Goodyear retread inspection process includes either Holography or Shearography inspections.

Shearography Inspection
Goodyear's new shearography equipment gives the latest technology in nondestructive inspection methods. It is capable of detecting very small anomalies that could affect tire performance. Its advantages are real time inspections through CRT screen viewing and video data storage. It has the capability of bead to bead inspection.

Holography Inspection
Holography is a very reliable technology of nondestructive inspection capable of detecting very small anomalies that could affect tire performance. It has been used by Goodyear for many years to provide high levels of quality retreaded tires. It has the capability of bead to bead inspection.

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Courtesy of The Goodyear Tire & Rubber Company