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An ES owner (not a part of this forum) recently experienced a blowout of the

left main after 140 hours ( don't know how many landings that equates to but

he makes mostly cross country flights to date). The McCreary tire was totally

devoid of rubber on the inside (maybe the first 1.75 inches). The outer most

threads were worn completely thru and the inner threads were showing wear.

When we replaced the tires last night I noticed the left main had a lot of

"wobble" in it when moved (with the plane on jacks). You  know, hold the tire

and move it forward, backward, in, out, twist etc to observe how much movement

could be attained. We were searching for reasons for the accelerated wear.



Is this movement (wobble) normal? The right main does not exhibit the same

movement characteristics. There is some slop but not the movement of the left.

The right tire had significant wear to the inside also, but no threads were

showing at changeout. He said most of his turns on the ground were to the left

(back taxi etc) when he had the choice to make. He felt this could have

contributed to the accelerated left tire wear.



Neither of the tires were significantly worn to the outside. Also, neither

were worn much at all at the center 50% of the tire. Could the absence of wear

of the center be contributed to tire pressure? Too low of pressure?



The toe in and other landing gear setup specifications described in the plans

were observed.



Goodyears have replaced the McCreary tires. A noticeably harder compound was

seen.