Bigrenna wrote: The one thing I think that is often overlooked is the long term stress of all that weight constantly wiggling at the end of the gear. Sure the gear can take it in the short term, but 50lbs at the axle is quite a large moment compared to how the Cessna engineers anticipated. Depending on the wind and my speed, I often feel the shake of the tires. No matter how many times I fly it, I still have a subtle panic when it happens. .....

When I went from 800's to 850's on my C150/150 taildragger, I noticed that shake.
You could look out the window & see the tires wiggling.
Ditto on the "subtle panic"....

Bigrenna wrote:

DENNY wrote:...so the plane is locking in on the 29" inch buffed air hawk.

The one thing I think that is often overlooked is the long term stress of all that weight constantly wiggling at the end of the gear. Sure the gear can take it in the short term, but 50lbs at the axle is quite a large moment compared to how the Cessna engineers anticipated.

Depending on the wind and my speed, I often feel the shake of the tires. No matter how many times I fly it, I still have a subtle panic when it happens.

Just something to think about...

True enough. And, depending how you use these things, you may want to consider eddy current inspection of your gear every once in a while. That Cessna gear takes a lot of forces in its lifetime, and I know of guys who've had them fail. Power users, but.....

MTV

Ok, here's an interesting twist to the FA 337 story. Subject came up on Facebooks 180/185 page. A poster from Alaska says he submits a 337 and makes a logbook entry based on CAR 3. The certification basis of the 180, 180A and 180B is CAR 3 Nov 1949.

Heres what CAR 3 says about Tires:

§ 3.362 Tires. A landing gear wheel may be equipped with any make or type of tire, provided that the approved tire rating is not exceeded under the following conditions: (a) Load on main wheel tires equal to the airplane weight divided by the number of wheels, (b) Load on nose wheel tires (to be compared with the dynamic rating established for such tires) equal to the reaction obtained at the nose wheel, assuming the mass of the airplane concentrated at the center of gravity and exerting of 1.0g downward and 0.31g forward, the reactions being distributed to the nose and main wheels by the principle of statics with the drag reaction at the ground applied only at those wheels having brakes. When specially constructed tires are used to support an airplane, the wheels shall be plainly and conspicuously marked to that effect. Such marking shall include
the make, size, number of plies, and identification marking of the proper tire. Note: Approved ratings are those assigned by the Tire and Rim Association or by the Administrator.

Minor and Major Changes:
CHANGES
§ 3.23 Changes. Changes shall be substantiated to demonstrate compliance of the airplane with the appropriate airworthiness requirements in effect when the particular airplane was certificated as a type, unless the holder of the type certificate chooses to show compliance with the currently effective requirements subject to the approval of the Administrator, or unless the Administrator finds it necessary to require compliance with current airworthiness requirements.
§ 3.24 Minor changes. Minor changes to certificated airplanes which obviously do not impair the condition of the airplane for safe operation shall be approved by the authorized representatives of the Administrator prior to the submittal to the Administrator of any required revised drawings.
§ 3.25 Major changes. A major change is any change not covered by minor changes as defined in § 3.24.

So, the question is since the 180 is not certified under Part 23 it does not need a Field Approval to install a TSO'd Tire that exceeds the required load rating for the airplane. Goodyear's book on this tire has the load rating at 2,765 lbs. So that exceeds the requirement. It would seem that a Logbook entry and a 337 submitted to OK City citing the appropriate facts would satisfy CAR 3 Minor change requirements.

Thoughts?

gunny

I guess the question is, has it worked for anybody?

Gunny wrote:....So, the question is since the 180 is not certified under Part 23 it does not need a Field Approval to install a TSO'd Tire that exceeds the required load rating for the airplane. Goodyear's book on this tire has the load rating at 2,765 lbs. So that exceeds the requirement. It would seem that a Logbook entry and a 337 submitted to OK City citing the appropriate facts would satisfy CAR 3 Minor change requirements.

A Form 337 is for a "major repair or alteration"--
if 26" GY's are NOT a major alteration, a simple logbook entry (and revised W&B) should be all that's required.
.
But I don't blame you for wanting to get something in writing from FAA,
but it seems like filing a 337 is just opening up a can of worms

Bearhawk_Cub wrote:I talked at length to Desser at Sun n Fun. This is what I found out. Grove is working on their TSO. Then Desser will package a 10" tubeless wheel and brake combo with their 31" tundra. I was told the STC would include a smaller tubeless tire for general use. Meaning buy an extra set of 10" wheels for times when the 31" are not needed. <snip>
John

While not STC'd, Grove's website now lists TSO'd 8-inch and 10-inch Tubeless wheels:
http://www.groveaircraft.com/bigtire.html

More options is good...

-Pat

I was talking to the director of maintenance of Seaplanes North at the Alaska Airman's Show and he said the owner of Seaplanes was working on getting an STC for the new Grove tubeless wheels on Cessna 170/180s etc. by the end of the year. The STC would also allow the new 850/29/31x10 Tundra Tires being offered by Desser. The 29" Tire will also become available around the end of the year. Sounds pretty good to me.

Right now Desser has a limited offer to buy new 10" Grove wheels and brakes( double puck) plus 31" Aero Classic Tundra Tires for $3995.00

I just can't bring myself to swim the CAR 3 river. It may be legal, but is an argument with current FAA folks. I also am going to forgo doing a Field Approval for the GY 26's.... to much work, expense, and risk.

I made a note in the Desser 31" thread. I talked to Desser at Oshkosh and it took awhile to get through to someone who is in the know... but I did get to that guy. He said they expect an STC with a large AML sometime in the fall that will cover their 26/29 and 31" tire using the Grove 10" wheel the ABI wheel will not be included). So, I'll just hang on a bit longer and see what rolls up.

gunny

[quote="Gunny"]I just can't bring myself to swim the CAR 3 river. It may be legal, but is an argument with current FAA folks. I also am going to forgo doing a Field Approval for the GY 26's.... to much work, expense, and risk.


Not to be an aXX, but GY26's---too much work, expense and risk? Huhh? You see them on all kinds of 170/180/185s all the time. Part 91 and 135. Everybody and their brother run them and have done so forever. Its pretty much standard equipment up north. Get a copy of a field approval and tire worksheet from someone who has them on an airplane exactly like yours. Then theres no arguing with some clueless FED. If your local Feds are being uncooperative, you need to make a trip to a region that understands what this is all about. Really, they work very well and last a long,long time in all conditions. Big bang for the buck.

Rockhopper-

I ask you to read through the thread. I went to the North Texas FSDO with not one, but three Field Approvals. They said well that's all fine, but you need to provide us all the data... when I tallied all the data they wanted it is equivalent of doing an STC... for one airplane. So, for me, it is too much work, expense and risk. Shopping a FSDO is not an option I see... my IA is here at the North Texas FSDO. As I said for me its not worth it. I'm not even sure they are the tires I want. I'll wait for the Dessers.

gunny

ask you to read through the thread. I went to the North Texas FSDO with not one, but three Field Approvals. They said well that's all fine, but you need to provide us all the data... when I tallied all the data they wanted it is equivalent of doing an STC... for one airplane. So, for me, it is too much work, expense and risk. Shopping a FSDO is not an option I see... my IA is here at the North Texas FSDO. As I said for me its not worth it. I'm not even sure they are the tires I want. I'll wait for the Dessers.

May be best to go to a different FSDO

One that excercises more practical thinking.

You are allowed to "Shop" for FSDO's' if you like.

As said before, many have been down this road, with no complications.

My IA has been working the GY 26" field approval since Apr 2016; every now and then the OK FSDO says we're almost there, but we need to change this wording or that TSO reference, and then a few more months go by ....

Does anyone have a copy of a field approval and required documentation to get GY 26s approved on a 55 wagon?

Thanks, Wes.

The highest un lit obstacle to aviation is the local FISDO office. Sad but true.

Schwarz wrote:Does anyone have a copy of a field approval and required documentation to get GY 26s approved on a 55 wagon?

Thanks, Wes.

Wes-

There are copies of Field Approved 337's on this website. As far as I know no-one has provided the supporting documentation.

gunny

Schwarz wrote:Does anyone have a copy of a field approval and required documentation to get GY 26s approved on a 55 wagon?

Thanks, Wes.

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https://backcountrypilot.org/knowledge- ... 5-skywagon

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I have 4-5 approved GY26 FA's I can email. Unfortunately I'm not sure if the owners want them publicly posted so I'd rather not do that yet. Sorry, Zzz. My IA sent them to me after he submitted mine. If mine gets approved, I'll post it on the knowledge base. PM me an email and I can forward them. They are all from 1 inspector in 1 FSDO, so maybe not the best data for other FSDO's, but it seems to work in Denver.

-asa

Gunny wrote:

Schwarz wrote:Does anyone have a copy of a field approval and required documentation to get GY 26s approved on a 55 wagon? Thanks, Wes.

Wes-There are copies of Field Approved 337's on this website. As far as I know no-one has provided the supporting documentation.
gunny

Curious what "documentation" you're referring to?
I would think that the required "tundra tire worksheet" would have to be worked up for each installation--
using that airplane's (new) W&B, and flying that airplane at extreme fwd & aft CG's.
IMHO a generic worksheet wouldn't be acceptable.
Seems silly to have to reinvent the wheel each and every time,
but silly seems to be one of the things the FAA excels in.

Thanks everyone for the feedback, asa keep me informed how things turn out.

Wes

asa wrote:I have 4-5 approved GY26 FA's I can email. Unfortunately I'm not sure if the owners want them publicly posted so I'd rather not do that yet. Sorry, Zzz. My IA sent them to me after he submitted mine. If mine gets approved, I'll post it on the knowledge base. PM me an email and I can forward them. They are all from 1 inspector in 1 FSDO, so maybe not the best data for other FSDO's, but it seems to work in Denver.

-asa

Thanks. Any 337s for field approval or approval data can be emailed to [email protected]. We had an issue before with people thinking their field approval was somehow intellectual property and didn't want it posted for public consumption, so make sure you clear it with the owner lest they get up my ass. Could get around it by saying "N1234FU has this mod" and people could order the CD, which is data freely available to the public, but I'd prob still get a lashing. If someone doesn't want their N-number posted on here, I'm not going to force it.