Does anyone ever use those stick-on wheel weights to fine-tune their tire balance?

I've got a question about these tires and don't want to start a new thread.

I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires".

The Desser tires would appear to be applicable if they are "type III" but I can't find clear definition of what that means. I found reference that it indicates a tire which is fat by comparison to it's wheel width, which seems to imply a balloon type tire but that's all I know so far.

The STC indicates the owner waives rights to compensation, so I'm hoping this all comes together easily.

hotrod180 wrote:Does anyone ever use those stick-on wheel weights to fine-tune their tire balance?

I have desser smooth 8.50x6 mains and I had to use a ton of weight to balance them. Both with, and now without tubes. Not too big of a deal on the mains as you can tap the brakes on lift off. Pretty much all my take offs and landings are done with a short field in mind, grabbing full flaps right as I tug on the stick and getting it off the ground about as slow as it will fly (40 or a little under) was still enough tire speed to get some good shaking. The 8.00x6 desser nose wheel was the same way. And that one you really have to balance or it's a nasty feeling you can't make stop. Figured it was normal to need some weight, but mine all have taken a lot of weights to balance out. Part of the problem is with the small wheels we run the weights are a long ways from the outside. Looks kind sucky with all the weights on there but it is what it is...

aftCG wrote:.....I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires"......

I'd say you've got it made, as the Desser smoothies are 4-ply.
Kinda surprised that's the way your STC reads--
I think those Dessers are the only 850x6 4-plies I've ever heard of.
The 850 STC for my C180 (by North Sound Aviation) specifies 6 ply.

aftCG wrote:I've got a question about these tires and don't want to start a new thread.

I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires".

The Desser tires would appear to be applicable if they are "type III" but I can't find clear definition of what that means. I found reference that it indicates a tire which is fat by comparison to it's wheel width, which seems to imply a balloon type tire but that's all I know so far.

The STC indicates the owner waives rights to compensation, so I'm hoping this all comes together easily.

Ummm, maybe call Desser, and/or your mechanic who is going to have to sign off the installation anyway????

MTV

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mtv wrote:

aftCG wrote:I've got a question about these tires and don't want to start a new thread.

I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires".

The Desser tires would appear to be applicable if they are "type III" but I can't find clear definition of what that means. I found reference that it indicates a tire which is fat by comparison to it's wheel width, which seems to imply a balloon type tire but that's all I know so far.

The STC indicates the owner waives rights to compensation, so I'm hoping this all comes together easily.

Ummm, maybe call Desser, and/or your mechanic who is going to have to sign off the installation anyway????

MTV

Because Desser didn't know. If you use their web page to look up tires by aircraft type it lists these 850-6 tires, but doesn't say anything about them not actually being approved on the type certificate (they aren't). When I asked about an STC for them their tech help backed out of any useful answer.

And because my mechanic is a bit phone elusive, and his opinion will be that I'm the aircraft owner and should be up to speed on my aircraft paperwork. The responsibility of aircraft safety (and compliance) is on me, so I'm taking it seriously. Hence, me looking into the details of using tires I have not yet seen installed legitimately.

My only real question was about the definition of "type III".

As an aside, I have noticed that people who brag about their large tires, Scout landing gear, and Borer props tend to shut up and disappear when you ask them about the paperwork side of things when it comes to Citabrias.

I've spent the past several months going through my logs and comparing them to the 337s and STCs, ADs and all that stuff we should know about planes we are responsible for. It has given me an image of what my plane has gone through in the past 52 years. As you can imagine, it has a story. The right rear window used to open. It used to have a glider tow hook. It has an auto gas STC. My EI engine instruments, LED strobe landing light and Whelen strobes are all clean installations with proper paperwork.

Unless someone has not documented it, my landing gear hardware was last replaced in 1988. There's a factory bulletin urging owners to ditch the old style bent U-bolt main gear attachments and go to the type which is basically bar stock with two holes (and only $177 each) and thru bolts suggests replacing them all every 5 years. I plan on having all new hardware handy when my annual is done so my mechanic can do the hard stuff.

That's my thinking. Sorry if it was a dumb question.

aftCG wrote:I've got a question about these tires and don't want to start a new thread.

I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires".

The Desser tires would appear to be applicable if they are "type III" but I can't find clear definition of what that means. I found reference that it indicates a tire which is fat by comparison to it's wheel width, which seems to imply a balloon type tire but that's all I know so far.

The STC indicates the owner waives rights to compensation, so I'm hoping this all comes together easily.

Here is some information that explains the definition of Aircraft Tire "Type". Looks to me like The Desser 8.50-6 is a Type lll because it displays only the width (8.50) and the wheel diameter (6). The ply doesn't appear to matter in determining "Type"

Tyres
The very earliest of tyre designs were called Type I and were referred to only by their outside diameter e.g. 27" which is a common fitment to aircraft such as the Harvard or P51 Mustang.
General Aviation tyres are generally Type III designs and include the most widely used sizes such as 5.00-5 and 6.00-6. These measurements refer to the section width of a tyre and also the rim ledge diameter (or the hole in the middle) hence a 6.00-6 is 6 inches wide and sits on 6 inch wheel.
Three Part Name Sizes cover most of today’s designs and typically describe the Outside Diameter, Section Width and Rim Ledge Diameter e.g. 15x6.00-6, the tyre is 15 inches tall, 6 inches wide and sits on a 6 inch wheel. Some tyres in this classification are preceded with an ‘H’ which identifies the tyre as having a higher percentage deflection.
Metric sizes are the same as three part name sizes but the Overall Diameter and Section Width are replaced with millimetres but the rim sizes remains in inches, e.g. 380x150-5, it’s imperial equivalent is a 15x6.00-5.
Radial tyres are also the same as three part name sizes but the dash preceding the rim diameter is replaced with the letter ‘R’ e.g. 32x8.8R16

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formandfunction wrote:Desser 850's are tso'd. They have permission to manufacture the tire to that model standard.
I installed that standard manufacture tire with a seperately purchased stc. Nothing complex of iffy about it.

What m/m aircraft, and which STC?

For AftCG, I'd say get that STC install the Desser tires and never look back.
Kudus to you for wanting to go through your airplane paperwork and make sure it's all good.
I went through mine and ended up having to do a 2-page airframe logbook entry & several 337's for modifications
"previously installed by others" to get everything squared away to my satisfaction.

FWIW here's a link to a pdf of Goodyear tire info,
might shed some light on "type 3" tires.
Basically it's as SkyLarkin explained.

http://www.aps-aviation.com/wp-content/ ... e-data.pdf

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I'm about due for new tires, any more pireps on the Dessers? My C180 came with 700s that are getting worn out and I'd like to put on 8.50s. Debating Dessers vs Goodyears.

Wondering how they hold up on pavement and if there are any more wobble issues out there?

FWIW I like Airtracs. Cheaper than GY's and I've always gotten good service out of them.
BTW 800x6 4-ply tires are included on my 53 C180's factory equipment list. To be legal, youll need an STC for 850's.
I have an 850 STC from North Sound Aviation, but it specifies 6-ply tires.

BazzLow wrote:I'm about due for new tires, any more pireps on the Dessers? My C180 came with 700s that are getting worn out and I'd like to put on 8.50s. Debating Dessers vs Goodyears.

Wondering how they hold up on pavement and if there are any more wobble issues out there?

If you want to come up to Boulder to inspect mine after about 30 hours (based on pavement), let me know. Honestly I didn't balance them and even forgot to match the markings on tires/tubes and I've never noticed anything weird. Maybe I just land too slow...

-asa

formandfunction wrote:Desser 850's are tso'd. They have permission to manufacture the tire to that model standard.
I installed that standard manufacture tire with a seperately purchased stc. Nothing complex of iffy about it.

I've held off in replying to this because I fear that a TSO discussion might be right up there with oil and the downwind turn.

A TSO label is no indication that I can put something on my plane.

I deal with TSO issues as part of my job so maybe I can put a spin on this that isn't quite as bad as paying taxes or getting a colonoscopy.

I'll start with a different example of a TSO issue and then get back to the tires. In my job I recently had a supplier disclose in issue with a seat cushion they made for my employer, which we insist be certified under TSO C72c (which talks about using the seat cushion as a flotation device).

Well the supplier had made what they thought was a trivial change a few years ago and they didn't realize they had to re-test and validate under the TSO. I'm using C72c because it's a simple one. Basically the cushion needs to float a 14 lb weight for 4 hours, and describes some very specific laboratory requirements to be consistent. The change the supplier made had nothing to do with the flotation components in the cushion (it was only a fabric change) but the requirements are still quite clear*.

By the way, 14 lbs is about what a human head weighs, and is the same factor used in certifying life jackets for boating.

Still with me? There's a quiz, so don't nod off.

In the future you'll want to parse the words "is certified under TSO blah, blah" as opposed to "meets the requirements of TSO blah, blah". Many TSOs are simple in nature and vague. C72c is sort of one of those, and it is just as set of requirements (Standards actually, hence the S in TSO) that the manufacturer has proved to the FAA they meet. Once a company has the TSO paperwork they can sell a product and claim it meets the TSO.

That doesn't mean that it will save your life, function better than another option or make you feel better about yourself. Say your head weighs 17 lbs because of that steel plate you had put in. You're screwed.

In this case the Aero Classic 8.50-6 4 ply tires I keep referring to as Desser tires indicate they are approved under TSO-c62e. I just read TSO c62e and it is actually the most complete Technical Standards Order I have yet seen. It speaks to the durability, speed rating, etc.

I have to admit to being a bit butt hurt that my state of the art motorcycle tires cost about $350/set and some oversize wheelbarrow tires for my plane will be $670 with tubes. They won't even have 100 miles on them when I replace them. But this is a case where seeing the TSO c62e gives me confidence because the test are pretty tough.

Bottom line, if your TCDS says the tires on your plane must meet TSO c62e then you cannot install tires that do not have the TSO c62e label on them. Meets is not acceptable in this case.

In my case my TCDS has no reference to TSO c62e, but does quite specifically list that my biggest tires I can use are 8.00-6. The TSO grants me no extra leeway ("hey they're certified so it must be okay"), nor do I need to make sure tires I buy meet the TSO.

Only by using the STC referenced earlier, along with a 337 and updated W&B can I legally install the 850-6 Aero Classic tires.

Back to "meets" the requirements of...
Let's use something dear to us all: ADSB out. It's no secret that you can buy an ADSB setup or even a Garmin G5 for your experimental plane and save a metric boat load of cash. What's the difference between the TSO approved item and the non TSO item? In many cases: Paperwork. Meets just means that a company is real damn sure that the product they're producing would pass all the tests if they coughed up the cash.

It costs a ton of money to prepare for TSO. You're usually paying 3rd party individuals to do the conforming, testing and documentation and those folks like to get PAID. It can take months or years and you get to deal with the friendly FAA while you pay employees to organize all your ducks and until you get paperwork you have no product to sell. We can and do moan about the price of airplane parts but certification costs are the biggest driver. The simple and reasonable truth is costs of TSO approval are carried on the backs of the consumer.

*The supplier quickly remedied their paperwork, all parties are happy and there has never been an actual safety issue.

One step closer. Fingers crossed on my first annual going on right now.

aftCG wrote:....I would like to put a set of these on my 7ECA Citabria. The TCDS does not show 850x6 tires on the approved list but there is an STC (SA3019WE) which allows "8.50 x 6.00 4-ply rated, Type III aircraft tires".....

Interesting....
The Desser smoothies are the only 4-ply 850x6 tires I've ever heard of, and they were introduced just a couple of years ago.
But that STC you linked is 43 years old, and does indeed specify 4-ply 850's.
I wonder who made them in 4-ply back in the day?

I don't know, but the other STC owned by the folks in Alaska not only specifies 6 ply, it specifies they be Goodyear or Dunlop. I don't see where Dunlop is currently in the airplane tire business.

I did notice that the label on the Desser tires does specifically say "type III" so that should help my A&P/IA to connect the regulatory dots.

The 850 STC for 180's which I have also specified 6 ply, no brand names though.
So technically the Desser 4-ply smoothies aren't a legal option for me.