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B747 aircraft tire tread groove depth

Hi, Is there standard groove depth used for aircraft tires
e.g. 49 x 17 type VII aircraft tire what would be the tread groove depth of a new tire , is it 6mm?

any references where i can find these ? i looked up michelin, goodyear tire manuals they dont giv tread groove depths?

thanks

Do you mean a new tire production depth, or minimum depth in operation with respect for replacement of the tire?

The tire grooves vary in depth when new or retreaded, depending if it's a center or outer groove.

In operation, a tire must be replaced at the first sign of underlayers (eg, cord). Generally tires aren't allowed to go that far before replacement (except in Russia).

want for a new tire, 49x17 or 17 -20 type tires...

is there any place i could find this info, i tried looking at tire manufacturers but they dont specify tread groove depth,

:sad:

Tread re-enforcing cords showing is permitted iaw the MM. Cuts to the cords, although metal now, tyre should be replaced.

Specifically from the mx manual, reference ATA 32-45-04; the areas applicable to the original posters question are highlighted:

Quote:

D. Examine the tires for worn areas.
(1) Measure the depth of the tire tread groove at three points that are
equally spaced apart.
(2) If the average depth of any groove is 1/32 inch (0.79 mm) or less, the tire must be replaced at the next convenient maintenance opportunity.
(3) If the tread belt ply (radial) or carcass ply (bias) shows at any location, the tire is not serviceable and must be replaced.
(4) If the tread is worn so that the cut protector (radial) or tread reinforcement ply (bias) shows at any location, the tire must be replaced at the next convenient maintenance opportunity.

NOTE: If the cut protector (radial) or tread reinforcement ply (bias) shows, the tire should be replaced as soon as possible. If necessary, the tire may be used for a small number of landings until it is replaced. However, you may not be able to retread the tire if you leave the tire in service too long with this condition.

Quote:

Hi, Is there standard groove depth used for aircraft tires

I would not assume that there is a standard for new tires, the standard is probably set by the manufacturer and wear based on composition of material.

As for a tire being unservicable, it is usually common to remove on spot of the indicator ply. This ply has no other function but to warn of being close to an actual functional layer of the tire being close to damage. I have seen 3 layers of indicator ply exposed (on retreads), they reapply the indicator tread over the old often.

May not be your interest but looking at a tire that was drug flat shows the many (structural chords) that holds a tire together. A bald tire is nothing more than a tire that has a bit less traction on a wet runway. Not a major concern.