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Have you seen the jump in tire prices lately!
WOW, a new pair of Goodyear Flight Custom III main gear sneakers for your Bonanza or Baron could set you
back from $300 to $400!
Now don't get me wrong, I've had great tire
wear and performance from the Goodyear Flight Custom II and III tires that I
have used over the last four and a half years and some 800 hours, but GEEZ,
these prices are getting crazy. 
Enter CSOB thinking and Desser's new
non-destructive testing technology! 


Well, after significant prodding of my IA
(over several years mind you), he finally relented on his long standing
resistance to a retread tire on a retractable gear aircraft. At my most recent
annual we fitted a Desser Aero retread 5.00 x 5 x 6PR on a Flight Custom III
core and did the gear retraction checks required for the annual. All clearances
were fine and no issues were noted. After about 11 months in service, my Desser
Aero retread nose tire is showing no signs of wear and remains vibration free.
How can this be? The OWT's (old wives tales)
about retreads for GA aircraft are littered with disaster stories. Yes, that was
probably true many years ago. Enter new technology in the form of Laser
Shearography that Desser now employs! I'm told by Desser representative and
Bonanza owner, Jim L., that
this has had a major uplift in their retread quality.

Laser Shearography Test Machine
Good
Shearography Images
Bad Shearography Images

Prior to Laser Shearography non-destructive
testing, the few manufacturing errors in the retreading process got thru and yup
you guessed it, the CUSTOMER found the defects
.
Read the Desser Retreading info
HERE
Read more about Laser Shearography
HERE and
HERE and
HERE
Assuming that my nose tire continues to
perform well, my intentions are to replace my Goodyear Flight Custom III main
tires with Desser's retreads ($89 vs $204 on 6/2009). In fact, Desser has said
they can even take your cores (in good shape of course) and retread them for you
and return them to you. Give them a call 800-247-8473 for more info on this
service.
My plan is to take my 6.50 x 8.00 x 8PR
Goodyear FCIIIs off when they have just a little groove remaining and send them
to Desser for retreading. I was quoted $65 each with me paying the shipping on
the cores to them and they pay the freight back to me. I get to feel good about
having a "known core" tire back on my plane plus I'll sleep better knowing I
helped Al Gore save the planet from another pair of tires in a landfill tire
fire! LOL
NEWS FLASH 6/11/2009:
I received my Goodyear FCIII cores
back from the Desser retreading service. Pics are below:

Note the "R1" in the picture on the right.
This is indicative of "1st Retread" cycle.
Here are videos of my gear swings with Desser
retreads at all three positions. No rubbing or airframe clearance issues
Video 1
Video 2
Read the Aviation Consumer 2008 Test Results
HERE
Read the Goodyear Tire Data
HERE
Read the Goodyear Tire Maintenance Manual
HERE
Read the Michelin Tire Tech Data
HERE
PS: Beech Talker, Rick O., was at a Michelin
presentation in which the rep stated that inflation of 90% to 105% is considered
"acceptable operating parameters". Anything less than 80% is considered a "FLAT
TIRE"! SO please regularly check your tire pressures, especially around the
change of seasons and when you traverse temperature zones in the country. When
Rick asked about high quality retreads, the Michelin rep stated that Michelin
recaps were better than their new tires!
Here's the Aviation Consumer 2008 Test Results
Narrative:
By Joseph (Jeb) Burnside and Martin Schneider
While car tires are all about the
finer points of traction and resistance to hydroplaning, the best we can hope
for with airplane tires is that they’ll make it through a couple of annuals.
To do that, they need a lot of tread depth, the right rubber compound and a
pilot whose idea of making the first turnoff doesn’t involve landing with the
brakes locked.
Heat is hard on tires, but landings chew up the
rubber so to find out which tire is top dog, we conducted the second Great
Florida Tire Death Match, subjecting each of 11 new tires to 300 blistering,
rubber-burning simulated touchdowns on a flat stretch of I-75. Conclusion?
He with the most tread wins, and that would be the Goodyear Flight Custom III.
In this case, "wins" means
delivers the most landings for the money—in
other words, the best value. But that doesn’t mean
the most expensive tire is always the best choice for every owner. More on that
later, but first, on to the tests.
Do Over
If most of your flying is from A to
B, you probably don’t do many landings, even if each "landing" might
be labeled a series of controlled collisions. For many owners, tire replacement
is more about age—
weather-related cracking, for example—than
it is tread wear. Still, smearing rubber on the runway is what it’s all about
so we dug out our test rig, mounted it on the trailer, bought a sample of most
6.00 X 6 new tires and tubes and got busy.
As shown here, the rig consists of a
pneumatically operated pivoting arm mounted on a
utility trailer towed by a pickup truck. The arm is activated by a valve—call
it an air-powered gear selector—that
reasonably simulates a retractable gear airplane by allowing a tire touchdown
and retraction about every six seconds.
When we conducted these tests four years ago, we simulated 200 landings, but
this time we upped the ante to 300, albeit with a slightly lighter weight load
on the trailer. We also skipped the skid destruction test, which involved a
mounted wheel and tire touched down at 30 MPH on a closed runway. We wanted to
know how the tires dealt with this abuse. Some did, some didn’t.
Of the 11 tires tested in 2004, we rated six as unserviceable after the skid
test. There wasn’t much to gain from repeating it this year, so for our 2008
edition, we substituted a two-mile taxi test at 30 MPH to test heat buildup. We
measured the tires’ temperature before and after the taxi test and from there,
we went right into the simulated landings. We also simulated a faster landing,
at between 65 and 70 MPH, instead of 55 MPH or so in 2004. We chose this speed
to better approximate the 60-knot
touchdown many tires see in actual use.
Metrics
We weighed and measured each tire before
and after the tests. In addition to tread depth, we measured diameter, finding
that most tires are less than 1/8-inch out-of-round.
As one might expect, the less expensive tires displayed the greatest
variation; premium tires from their respective manufacturers exhibited better
quality control with regard to roundness. Goodyear’s Flight Custom, for
example, was spot on for roundness, as was the Michelin Aviator. The inexpensive
Specialty Aero Trainer, Condor and Super Hawk were at least 1/16-inch out of
round.
Weight varied, too, with the less expensive
tires generally being the lightest, given that their construction uses less
steel, fabric and/or rubber. Goodyear’s top-rated Flight Custom III was the
heaviest tire, at 11 pounds, 4 ounces, followed by Desser’s massive Monster
retread at 11 pounds. The lightweight was Specialty’s Aero Trainer at 6
pounds, 13 ounces.
Rubber hardness can be a predictor of tire
durability, although in the end, we think tread depth trumps all.
We measured hardness with an analog durometer at
five points along each tires’s tread. Interestingly, we found that hardness
often varied from point to point along the tread’s circumference and from
shoulder to shoulder. Again, you get what you pay for. The cheaper tires seemed
to vary in hardness while the premium products were more consistent.
Prior to hitting the road, we marked each
tire’s sidewall into eight segments and using a digital depth gauge, we
measured groove depth at each segment mark at the beginning and end of each
test. Although the tires vary in number of grooves, to make things simple, we
used only wear data from the two center grooves, averaging the 16 values for an
overall wear indication. No surprise that the data showed
the centers of the tires wore more than the outer grooves.
Hot Stuff
As noted in our previous report, heat
is hard on tires and we were surprised how much variability in heat rise we
recorded during the two-mile taxi test. While the Goodyear Flight Custom III ran
the coolest, some of the least expensive tires were right behind it, such as the
Condor and the Super Hawk. Desser’s Monster and the Specialty Air Hawk ran the
hottest, as shown in the chart at left.
We also recorded before and after temperature
rise during the 300-landing cycle test. Here, the cheaper tires acquitted
themselves well, with the bargain $45.95 Aero Trainer tire showing a scant
2.3-degree rise. The Desser Monster and the premium Michelin Air topped the
scale in landing cycle heat rise, which while not a predictor of imminent
failure, is also not desirable, in our view.
To keep our observations consistent, we had
to park in the shade to prevent direct sunlight on the tire from contaminating
the data. For what it’s worth, even in Florida’s weak February sun, solar
heat rise was so significant that we think tire covers might be worth the
investment to reduce heat and UV damage. As described in the sidebar at right,
our long-term weathering test showed that UV and heat really trash tires,
turning the soft rubber brittle and badly oxidizing the surfaces.
Test Findings
As we learned in our previous tests,
if a tire is landed frequently, durability is a function of tread depth and wear
rate. Deeper tread is a strong plus, but if the rubber wears rapidly, the tire
might not last as long as one with shallower tread but a lower wear rate. The
additional variable is price and this has the largest impact on
value. From most to least, the tread depth ratio in these new tires was 1.6 to
1, but the most-to-least cost ratio was more than 3 to 1.
To make some sense of cost versus tread versus
wear rate, we constructed a simple formula. First, we established a wear rate
for each tire—in
other words, how much comparative wear each tire showed per 300 landing cycles
related to its total tread depth. We
used this to roughly calculate how many
cycles the tire would theoretically deliver and we divided this number into the
discount price to determine a value ranking. The number itself is arbitrary; the
ranking is useful. Our intent was to answer several questions: Which is the best
tire for minimum wear? Which is best value tire? Are cheap tires a better buy
under any circumstances?
First, overall wear, irrespective of tread depth and cost. The top three here
are Goodyear’s Flight Special, the Michelin Aviator and the bargain Super
Hawk, all of which had more than 95 percent of their tread remaining after the
test. Although this sounds good, here’s the problem:
Each of these tires started out with 20 percent less tread depth than the top
rated Goodyear Flight Custom and more than 30 percent less than Desser’s
Monster.
When total tread depth is considered against
wear rate and cost, a different picture emerges. At the premium end of the
market—tires
in the $100 and up range—the
Goodyear Flight Custom III tops the value equation because its .270 inch tread
depth exceeds its competition—mainly
its stablemate Flight Special and the Michelin products—and
the price differences aren’t that great between these tires. While it’s true
that the Flight Custom had a slightly higher wear rate, it wasn’t enough to
offset that generous tread depth.
At the lower end of the market—tires
under $100—the
wear rate grouping and price relationships were scattered enough that the
Specialty Air Hawk came out as a winner largely because of an edge in total
tread depth. Cheaper tires such as the Condor, the Specialty Aero Trainer and
Air Trac didn’t do as well because—you
can see it coming—they
started with less tread or they had a higher wear rate.
If there was a surprise for this round of
testing, it was the Monster retread. In our last test, we picked it as the top
value using a slightly different formula. But this time, its combination of a
slightly higher wear rate against the other tires and a higher price dropped it
from the top ranking.
This could have been related to more test cycles or the fact that the
simulated weight on the tire was lower. Also, the Monster’s rubber was among
the softest tested. Nonetheless, we still like the Monster as a good buy because
of its top ranked tread depth—good
protection against skids and lockups.
Recommendations
One caveat: Drawing take-it-to-bank
conclusions from what are actually very slim differences in actual tire wear
rates is problematical. But we’re comfortable making some general
recommendations.
Goodyear’s Flight Custom III came out at the top of our cost vs. observed
tread wear equation for two simple reasons:
The tire simply starts with a deeper tread than most of its competition and the
wear rate is comparable. The only tire with more tread, Desser’s Monster
retread, also features a slightly softer rubber compound—yielding
a durometer value of 61, vs. the Goodyear’s 63. Plus, the Flight Custom has
only two grooves, so it puts more rubber on the runway, thus reducing wear.
Specialty Tires of America (neé McCreary Tire and Rubber Company) came in
second and third with their Air Hawk and Aero Classic models, respectively. The
two tires started out with relatively deep tread and their rubber compound—at
72, the hardest we tested—kept
wear to a minimum. But it was low street prices that helped boost them to near
the top of the pack. The Air Hawk is a conventional four-rib tire while the Aero
Classic is designed for classic airplanes including warbirds, DC-3s and Beech
18s, according to the company, so it has a sidewall shoulder tread pattern
popular in the 1940s and 1950s. It’s designed for a particular look.
Michelin’s premium Air model came in fourth
overall. Although we think it’s a great tire, it suffers for lack of tread
depth and it’s priced with the Flight Custom. Michelin’s Aviator model had
much harder tread—second
only to the Specialty Aero Classic and Air Hawk—but
there wasn’t enough of it. Despite wearing well, it finished near the bottom
of the pack in value, after Desser’s Monster.
So, given the Flight Custom’s top-of-the-tire-pile
rating, is it automatically the best buy? Not necessarily. If you fly a lot, are
careful on the brakes and don’t want to be bothered with tire changes, the
Flight Custom is our top choice. It’s
worth the $146 (discounted) asking price.
But if your airplane sits a lot exposed
to weather—and
many airplanes do—your
tires will probably rot before they wear out their tread. In this case, second
tier tires such as the Air Hawk and Michelin Air are good choices. We don’t
recommend the cheaper tires at all, for two reasons: They start out with less
tread when new and given similar wear rates, the cost of changing them will
easily amount to a total higher than a more expensive tire would have in the
first place. Second, you need downside protection against a wheel lockup. We all
do this from time to time and if you lock a $51 Air Trac with .200 inch of
tread, it’s toast. Do the same with a Flight Custom and you can might get
another year or two out of it. And in the end, that’s all we can ask of a
tire.
Here's what happens when you run with tires
that have thin tread remaining AND maybe land long or try to make that first
turnoff. Please folks, save your brakes and tires - go around and set it up
right or just roll to the end of the runway (pics courtesy of BeechTalker YS)......Just a thought.

As expensive as owning and operating our
aircraft is getting, I encourage all Beechcraft owners to take the opportunity
to evaluate lower cost tire options. Even finding NOS tires on Ebay can be a
good option to lower your operating cost on this consumable.
Here is a great tire protectant product 303
Aerospace Protectant that has gotten a great pirep from Jeff S., an A36 owner.
If your airplane is tied down outside you
might want to consider this for your tires

Technical Info on 303
HERE

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