[Username Protected]

I was very interested to find out Embraer does not say to change our tires if you see the fabric showing on tires to some extent. See pictures below.





It’s basically say it has to be 9 inches in circumference to be unairworthy. There are a host of other items it calls out, but I did not know this. Also - you replace the tire when the tread is totally worn and there is no more tread groove at any point of the tire circumference.

Naturally - this doesn't make technical sense to me, but we fly Embraer's planes and we put our lives in their engineering mastermind hands.

[Username Protected]

That is what the book says, but every service center I have been to have recommended (demanded?) changing the tire when the inner groove is one gone and EEC has yet to push back.

[Username Protected]

We once did a cut-away of a new tire to show the thickness of the tire. When you reach the threads, you're not even 1/2 way through the carcass (as my not so great graphic shows). The tire is extremely thick in the tread area. According to the tire company, the grooves are wear indicators. I hope that improves your confidence about how deep you can wear them.

[Username Protected]

We replace when the inside groove is gone.

[Username Protected]

I’m going to push now as we have to be in a spot that performance is degraded.

Update: The tire above meets the requirements. It only was maybe 4-5 landings past the original picture before it wore more.

[Username Protected]

LOL! You got the most out of that tire.

[Username Protected]

I had a left main tire with similar wear to (Username Protected)’s as pictured above, it’s unnerving to land on a tire that’s showing threads but I put my trust in the Maintenance Manual. A trip to our shop and a few minutes in a bandsaw left me with two conversation pieces for the hangar. As you can see, there’s still a bit of meat left.

[Username Protected]

Has anyone tracked their replacement interval on 300 tires closely for an extended period of time?

I went through the logbook data (9 years) when I purchased mine and got an average of ~130 cycles for the MLG and 644 cycles for the NLG.

[Username Protected]

(Username Protected),

My first set of tires lasted 284 cycles, the second set was changed at 214 cycles. I've started tracking and recording the pressures more closely, bringing them up to 184 psi at the start of every trip. I'm anxious to see how many cycles we get out of this pair. The nosewheel was changed by maintenance due to a suspected vibration, so I don't have any real data on it.

[Username Protected]

(Username Protected),
Since wheels & brakes are among the costliest components per flight hour, when I was responsible for EEC, we used to look at this pretty closely. Cycle count factors were not only runway length and surface type, but greatly affected by tire pressure. We would even see cycle changes when new BCU software was implemented.
214 cycles was a nominal number for main tires and approximately 650 cycles for nose tires. Carbon brakes last longer when you heat them up, whereas steel brakes (on the Phenom100) last longer when you keep them cooler. I hope this helps.