4, 6, 8 ply tires?

[johncuyle]

10 hours ago, Tommy said:

"composition of rubber compounds. Types of fabric used in plys, design of bead cables. variance in manufacturing."

If the loading and rating are the same why and how do composition, type of fabric, and bead cables etc matters?

I don't look at those things when I buy tires. Should I? And why? 

(Car nerd rant:) These things matter a lot for wear, grip, and longevity.  Think about car tires.  You can purchase (even from the same manufacturer) multiple models of tire with the same load and speed rating.  A lot of times they'll vary in price and you can choose cheap tires which have very hard tread compounds and will be terrible to drive with poor heat absorption/retention/shedding characteristics, relatively low grip providing poor acceleration, cornering and (most applicable to airplanes) braking characteristics, poor resistance to hydroplaning, and so on, but will last 60,000 miles.  For more money you can buy much better, generally softer compound tires, probably with a better tread design, that will not last as long (say 20,000 miles) but will offer significantly better performance.  It is also important to consider the temperature ranges and surface temperatures a tire will operate on most.  Different compounds require different amounts of heat to work optimally.  

Aircraft tires have a much narrower performance profile than automotive tires.  They spend the majority of their time holding the weight of the aircraft while it is stationary, followed by being folded up into the aircraft.  For an aircraft that spends most of its time cruising up high, the tires will be cold when landing no matter what the ambient temperature is so it is desirable for them to build heat rapidly when stressed and survive a relatively extreme temperature increase.  Shedding heat is not as necessary since they don't see continuous stress.  For a trainer that spends a disproportionate amount if its time doing pattern work, the tires will heat cycle significantly more often, rarely see high altitudes and colder temperatures, and presumably should have compounds and construction which don't necessarily build heat as quickly and also shed it faster. 

I haven't had to replace the tires on my plane yet so I haven't researched the different models, but for car tires it is insane to buy without knowing your usage profile and doing significant research into what options are available to meet those criteria.  If you don't, you end up with crappy, 60,000 mile all seasons which are cheap but complete trash, and this for the single most important piece of performance and safety equipment on your vehicle.

[Tommy]

Agree on what you said (though I must confess, I will need to do a bit more research on the car tires)

What  I find a little bit unsettling is to extrapolate theories and data from car tires to general aviation. after all, like you said, the usage couldn't be more dis-similar! 

Thanks for the discussion on the temperature! Something I didn't quite consider but AFAIK, I don't think there is any manufacturers out there quote temperature data on the tires so makes it hard to decide what material and what made are best for the tire.

[Raptor05121]

Please, no more talk on tires. Between this forum and the Mooney Facebook group, I think some of you guys are rummaging through the garage looking for pitchforks.
 

[Tommy]

4 hours ago, Raptor05121 said:

Please, no more talk on tires. Between this forum and the Mooney Facebook group, I think some of you guys are rummaging through the garage looking for pitchforks.
 

I kindly disagree. I am still learning new things like, for example, the temperature cycle. And I am certain some MSers are too. We need not stop because some people are crying troll... Just like the United discussion, I was learning the statutory and contract law, then it got banned because few people were crying foul.

[Tommy]

17 hours ago, cliffy said:

Tommy- I didn't say one was better than another You asked what the difference was between them. I just stated what the differences could be with no judgement on quality either way.  

Sorry I mis-interpreted. So how's variance in manufacturing, affect the safety and longevity. @jetdriven made a few comments on "stiffer" and "thicker" being better based on his experience of 22 sets. Then I heard @RLCarter said softer compound may give better traction and cushion but make sure your tire pressure is up there. I am curious how your variance in manufacturing - specifically "composition of rubber compounds, types of fabric used in plys, design of bead cables," - can affect safety and longevity. It's another set of variables. 

[RLCarter]

@Tommy when it comes to tires they all have to meet a "minimum" of specifications, and how they do it is generally proprietary as far as construction and materials. The TCDS dictates the specifics and you get to sort out the rest. As I've said before the majority of failures can be traced back to improper inflation. There is 2 active threads on tires right now and someone posted that they had what they considered a cheaper quality tire on a main fail during a bad landing causing damage to the aircraft , while the higher quality tire on the other main did fine. My theory is the failed mains pressure was low for what ever reason and got the blame, tubes hold the air not the tire and unless the tire came apart (which I doubt) it didn't caused the problem. So short story long, install what meets the specs and then your budget.

[Alan Fox]

3 hours ago, RLCarter said:

@Tommy when it comes to tires they all have to meet a "minimum" of specifications, and how they do it is generally proprietary as far as construction and materials. The TCDS dictates the specifics and you get to sort out the rest. As I've said before the majority of failures can be traced back to improper inflation. There is 2 active threads on tires right now and someone posted that they had what they considered a cheaper quality tire on a main fail during a bad landing causing damage to the aircraft , while the higher quality tire on the other main did fine. My theory is the failed mains pressure was low for what ever reason and got the blame, tubes hold the air not the tire and unless the tire came apart (which I doubt) it didn't caused the problem. So short story long, install what meets the specs and then your budget.

From personal experience , Better quality tires , are tighter on the bead , long story short , if a tires bead slips on the wheel , it tears the valve stem.....That's one possible failure mode , if the tire was overinflated , it has significantly less traction , and will lock and burn a hole right through to the tube.... That's another possible failure mode ,   The cheaper tires I have worked with , (Airhawk , Airtrac , Aero trainer , Aero Classic ) all seem to have softer compounds , and much thinner casings...  It makes a huge difference.... There is a reason the Good retreads are only using Goodyear , and Michelin cores....

 

Edited July 31, 2017 by Alan Fox

[Tommy]

9 hours ago, RLCarter said:

@Tommy when it comes to tires they all have to meet a "minimum" of specifications, and how they do it is generally proprietary as far as construction and materials. The TCDS dictates the specifics and you get to sort out the rest. As I've said before the majority of failures can be traced back to improper inflation. There is 2 active threads on tires right now and someone posted that they had what they considered a cheaper quality tire on a main fail during a bad landing causing damage to the aircraft , while the higher quality tire on the other main did fine. My theory is the failed mains pressure was low for what ever reason and got the blame, tubes hold the air not the tire and unless the tire came apart (which I doubt) it didn't caused the problem. So short story long, install what meets the specs and then your budget.

Your theory certainly provides another possible explanation to the observation that I have made, namely, for every recommendation on an expensive tire, there is one for the cheaper version.  I wonder if people who "cheap-ed out" on a tire also more likely to cheap out on the tube or more likely not to inflate them with the right pressure because they aren't too concerned (ie. these are what we called a confounding factor). All the theories about tread depth, tighter beads, thicker and harder rubber, etc etc are great and make sense but need to be tested. What  Byron and Alan failed to understand is that they carried out what we call the observational study - conclusion drawn based on their own experience - its validity is right at the bottom of the evidence strength because there are lots and lots of biases and uncontrolled variables. Their "studies" will NOT be in any shape or from reproducible. And the simple observation again "for every recommendation on an expensive tire, there is one for the cheaper version" simply confirms the irreproducibility of their "studies."     

What about Aviation Consumer's test? A closer look at the article revealed the highly insufficient power (11 tires were all they testes), the seriously flawed methodology (there was no control, no blind, no statistical analysis, and using "simulated condition" which uses machines that are used to test car tires not GA tires), and highly sensationalized conclusion Goodyear TOPs. It doesn't surprise me at all. It's a consumer magazine not a science journal. It has a very limited budget and does not disclose any material support from anyone (*Goodyear, cough cough). Take a look at ANR headset reviews and it's the same kind of pattern! 

What can Byron do in this case? Well, couple of things. One, admit that he has just as much evidence on tires as every one else and every one flies / maintains the plane differently (surprise) and stop accusing people "cheap out" or "take risks" with their planes because there is simply no evidence to suggest that whatsoever or find more credible evidence than some magazine or, failing that, do some proper research himself (if it's going to be an observational study, it will probably take decades of meticulous collection of data). And certainly not these: "I don't think you're a pilot  or an aircraft owner   If its less, you go away from this board and never come back.  Deal? You're hopeless. Good day sir."  

Case and point: there was a discussion on AC43.13 on Mooney Pilots Facebook group and EVERY ONE - including Byron  - was opening champagnes to congratulate someone for narrowly avoiding having a much bigger tear down job on his spar except this one brave guy came out and said "wait a minute... what about this and this..." I learnt new things on my Mooney thanks to this HIGHLY experienced A&P aero engineer who was not afraid to speak out.

THAT IS WHAT FORUM IS ALL ABOUT. FOR DISCUSSION. FOR DISSENT. FOR DISSEMINATION OF KNOWLEDGE AND EXPERIENCE. IF WE ALL WE DO IS JUST AGREEING ON EACH OTHER. WHAT'S THE POINT?

 

 

 

[RLCarter]

Anytime you have a choice there will always be opinions, my tires & tubes were replaced due to age, they were 7+ yrs old but had very little use on them. My decision on the AirHawks was based on several things (1) I had used them on a 172 that was on lease back to a flight school and they held up (no failures) and lasted around 300 hrs if memory serves, which isn’t bad for a ton of less than perfect take offs, landings and unnecessary hard braking. (2) Admitting to myself that it could take time to master landing in the Mooney I saw no reason to wear out an expensive tire. Time will tell if I like them on my Mooney.

[carusoam]

Tommy,

what is missing is that we are not all alike, in how we use our tires, fly our planes, pay for stuff...

The mere fact we fly Moonies, we are often left out by the fine magazines like aviation consumer...

Listening to people like you mentioned is pretty far from perfect. We have a statistician that can tell you why.

The most interesting things I got out of their generous discussion is all the things ordinary PPs do that messes up the tire's health...

Stuff I haven't read about in magazines...

I bought some expensive driving shoes this year.  Hoping to keep the braking light enough to not lock up the tires.

Full flap landings, on speed, and even light braking still is too easy to lock the brakes...

I don't dare touch the flap switch! 

Its probably the camguard I don't use...

what is the perfect tire in the perfect flying world? How much does it weigh? Can it withstand my big feet?

Best regards,

-a-

 

[Tommy]

1 hour ago, carusoam said:

Tommy,

what is missing is that we are not all alike, in how we use our tires, fly our planes, pay for stuff...

The mere fact we fly Moonies, we are often left out by the fine magazines like aviation consumer...

Listening to people like you mentioned is pretty far from perfect. We have a statistician that can tell you why.

The most interesting things I got out of their generous discussion is all the things ordinary PPs do that messes up the tire's health...

Stuff I haven't read about in magazines...

I bought some expensive driving shoes this year.  Hoping to keep the braking light enough to not lock up the tires.

Full flap landings, on speed, and even light braking still is too easy to lock the brakes...

I don't dare touch the flap switch! 

Its probably the camguard I don't use...

what is the perfect tire in the perfect flying world? How much does it weigh? Can it withstand my big feet?

Best regards,

-a-

 

Ever so philosophical and insightful , @carusoam

What you had said is exactly what I have been saying all alone. Every flies and maintains planes differently.

On the issue of tires, where there is really no credible experimental evidence and the anecdotal evidence is also equivocal (half of the people said FC3, half said Air Hawk). One ought to be challenged to accuse others short changing or putting at risk of their planes by going for the cheaper tires. 

The issue here is that these people 1) think their own anecdotal evidence is better or more than everyone else's (I am sure many MSers here had changed more than 22 sets of tires that Byron claimed to have changed) 2) not knowing how to assess the validity and the power of an experiment 3) simply cannot take a dissent. 

And then along come Byron's friends... All lined up, hurling insults and innuendos.  Laugh out loud. 

 

Is this how MSpace been operating? Someone makes a claim, we then all agree, huddle, and suck each other's that-thing-Mucci-was-referring-to. Then someone says "but wait, I don't think you are right" Bang! He gets roasted for not a "community person", not a "team-player?"

[Tommy]

1 hour ago, RLCarter said:

Anytime you have a choice there will always be opinions, my tires & tubes were replaced due to age, they were 7+ yrs old but had very little use on them. My decision on the AirHawks was based on several things (1) I had used them on a 172 that was on lease back to a flight school and they held up (no failures) and lasted around 300 hrs if memory serves, which isn’t bad for a ton of less than perfect take offs, landings and unnecessary hard braking. (2) Admitting to myself that it could take time to master landing in the Mooney I saw no reason to wear out an expensive tire. Time will tell if I like them on my Mooney.

That's also my experience with Air Hawk too. Recently I had to replace one but before I did that I have done a bit of research and found really no credible evidence to say it's any worse than the expensive ones. My A&P also recommended it and Condor. I was then very surprised to hear someone saying how great FC3 are and it's not worth the money saved when you have to change tires more often or, even more outrageous, repair landing gear damage!! 

[Raptor05121]

I have Aero Trainers on my plane now that were new in 2013. They had a little bit of tread on them when I bought the plane in 2015, and here we are in 2017, I have about 200+ landings on them (the first 50-75 were really shitty, have had a few hard hitters since then) and now they are all pretty much bald.

All of the following prices are the lowest I could find after scouring all night, free shipping, 5.00-5 nose and double 6.00-6 for the mains and includes Michelin Airstop tubes:

Goodyear's Flight Custom III: $786.00
Michelin's Air: $696.00
Goodyear's Flight Special II: $558.00
Desser's Retreads/Goodyear core: $436.00
Custom's Air Hawk: $429.00


I think the price for what you get on the Desser retreads is handsome considering with the added sidewall strength of the Goodyear cores as stipulated by several of you guys earlier. I think my mind is made up.

 

[Alan Fox]

28 minutes ago, Raptor05121 said:

I have Aero Trainers on my plane now that were new in 2013. They had a little bit of tread on them when I bought the plane in 2015, and here we are in 2017, I have about 200+ landings on them (the first 50-75 were really shitty, have had a few hard hitters since then) and now they are all pretty much bald.

All of the following prices are the lowest I could find after scouring all night, free shipping, 5.00-5 nose and double 6.00-6 for the mains and includes Michelin Airstop tubes:

Goodyear's Flight Custom III: $786.00
Michelin's Air: $696.00
Goodyear's Flight Special II: $558.00
Desser's Retreads/Goodyear core: $436.00
Custom's Air Hawk: $429.00


I think the price for what you get on the Desser retreads is handsome considering with the added sidewall strength of the Goodyear cores as stipulated by several of you guys earlier. I think my mind is made up.

 

The flight special 2s are your best value.....I put them on inventory (used) planes I sell , believe me I am trying to  pinch every penny out of every dime , For 120 dollars , you will be pleased...

[Hank]

33 minutes ago, Alan Fox said:

The flight special 2s are your best value.....I put them on inventory (used) planes I sell , believe me I am trying to  pinch every penny out of every dime , For 120 dollars , you will be pleased...

That's why I use on my mains, with a Condor on the nose (it wears out faster, I'm guessing due to turning). It's almost time for a new nose wheel, I replaced all three in late 2012.

[Tommy]

FC3 is twice almost twice as much as Air Hawk. Will it last twice as long?

[201er]

1 hour ago, Tommy said:

FC3 is twice almost twice as much as Air Hawk. Will it last twice as long?

Perhaps it will last twice as long just sitting. Doubt it would last anywhere near twice as long on number of landings. Guess it depends on how you wear out your tires. Number of landings, bad landings, or age?

For me, it's a combination of the occasional bad landing which makes a flat spot and total number of landings. The flat spot will be the first bit to go when I'm running low on tread. So I get Airhawks cause they are good enough and I won't beat myself up too bad for ruining it.

[Alan Fox]

12 hours ago, Hank said:

That's why I use on my mains, with a Condor on the nose (it wears out faster, I'm guessing due to turning). It's almost time for a new nose wheel, I replaced all three in late 2012.

My guess is you know how not to lock up your mains , good landing technique....  Its usually the other way around....

[Hank]

42 minutes ago, Alan Fox said:

My guess is you know how not to lock up your mains , good landing technique....  Its usually the other way around....

I rarely use my brakes, even at my 3200' home field.    Even when I need them, I rarely touch the brakes above 50 mph. Saves brake pads and tires. Never use brakes on grass except when stopping to park.