This condition occurs when a tread rib partially or totally peels off in a circumferential direction. Usually beginning with a cut in the tread, it results in a circumferential delaminaiton of a tread rib away from the tire carcass.
Remove the tire from the aircraft.
In the case of transverse cuts on the tread, remove the tire if the cut is deeper than the tread groove or extends across a rib from groove to groove.