The International Cessna 170 Association

I purchased a set of 26” tires from a friend that I would like to put on my 170A. Is an STC required? If so, where can I find this? I’ve done a search on here, but no joy.

Airframes Alaska has an STC for 26” tires: (but be aware it calls for only certain makes of tires, and original brakes may be insufficient when larger tires are installed):

http://www.airframesalaska.com/v/vspfil ... %20AML.pdf

Wyoming1 wrote:I purchased a set of 26” tires from a friend that I would like to put on my 170A. Is an STC required? If so, where can I find this? I’ve done a search on here, but no joy.

An STC or some airworthiness approval would be required for 26” tires to be installed on a Cessna 170. You should get advice/help from your IA who would ultimately sign off on that installation for an annual inspection.

Thank you both.

Wyoming1,

I own a '50 170A with Goodyear 26" tires on it. So here is the Info you need.

If you bought some used AlaskaBushwheel 26" tires, call them and give them the serial numbers off of your tires. They may sell you their STC.

There are NO STC's for Goodyear 26" tires on our 170's. CubCrafters in Yakima have STC's for Pipers and the Goodyears.
Alaska Bushwheels have an STC for Their Own Propriatory 26 inch bushtires. If you call them and ask for the STC for Goodyears, they will politely refuse your request, which makes sense as they spent the money to get their own tires certificated. I understand their stance in this, but I did call them and got the story.

If you have Goodyears, you have two choices. Run them on your own, because 26" tires do work on the aircraft. But there is no legal basis for running them. OR.....
Go through the process of a field approval through your local FSDO. It can be done. I had other members paperwork to use for the process, but each FSDO may want to fill it out their own way and ask you for specific info. Some may be more lenient, and others are pretty particular on wording and the parts you can use.

I will tell you that the stock single puck brakes will not stop the 26" tires in a hurry, but I used them for some time and was happy with them.
What I found out though Alaska Bushwheels and my own FSDO person, is that the larger (26" and bigger) tires can stretch the bolts in the 3 bolt wheels and you may need to replace the bolts at your annual inspections. ( A friend of mine had this happen to him ) Though my FSDO guy was willing to approve my 3 bolt wheels, both him and Alaska Bushwheels suggested getting the 6 bolt wheels......which can only be used with the double puck brakes. And they require the double pucks on their own STC'd tires.

I was pretty nervous about moving to the double pucks on my 170 as I did not want to stand it on its nose. So have been careful in working up how much brake I'm using when landing. But have not found it to be a problem at all so far.

So there you have it. Feel free to contact me if you have other questions.

wabuchanan wrote:Wyoming1,

I own a '50 170A with Goodyear 26" tires on it. So here is the Info you need.

If you bought some used AlaskaBushwheel 26" tires, call them and give them the serial numbers off of your tires. They may sell you their STC.

There are NO STC's for Goodyear 26" tires on our 170's. CubCrafters in Yakima have STC's for Pipers and the Goodyears.
Alaska Bushwheels have an STC for Their Own Propriatory 26 inch bushtires. If you call them and ask for the STC for Goodyears, they will politely refuse your request, which makes sense as they spent the money to get their own tires certificated. I understand their stance in this, but I did call them and got the story.

If you have Goodyears, you have two choices. Run them on your own, because 26" tires do work on the aircraft. But there is no legal basis for running them. OR.....
Go through the process of a field approval through your local FSDO. It can be done. I had other members paperwork to use for the process, but each FSDO may want to fill it out their own way and ask you for specific info. Some may be more lenient, and others are pretty particular on wording and the parts you can use.

I will tell you that the stock single puck brakes will not stop the 26" tires in a hurry, but I used them for some time and was happy with them.
What I found out though Alaska Bushwheels and my own FSDO person, is that the larger (26" and bigger) tires can stretch the bolts in the 3 bolt wheels and you may need to replace the bolts at your annual inspections. ( A friend of mine had this happen to him ) Though my FSDO guy was willing to approve my 3 bolt wheels, both him and Alaska Bushwheels suggested getting the 6 bolt wheels......which can only be used with the double puck brakes. And they require the double pucks on their own STC'd tires.

I was pretty nervous about moving to the double pucks on my 170 as I did not want to stand it on its nose. So have been careful in working up how much brake I'm using when landing. But have not found it to be a problem at all so far.

So there you have it. Feel free to contact me if you have other questions.

Great info, thank you kindly. This is the information I desperately needed. What is the best way to contact you directly so as not to muck up the forum?

In addition to buying double puck brakes, (see F. Atlee Dodge's STC SA02231AK), you'll want to upgrade to steel axles as well as NAS bolts and nuts to replace the weaker original AN hardware. You don't want to be this guy. See also SAFO10007 on this subject.
Finally, Bruce added a 337 for 26" Goodyear's on entry 166 here.

n2582d wrote:In addition to buying double puck brakes, (see F. Atlee Dodge's STC SA02231AK), you'll want to upgrade to steel axles as well as NAS bolts and nuts to replace the weaker original AN hardware. You don't want to be this guy. See also SAFO10007 on this subject.
Finally, Bruce added a 337 for 26" Goodyear's on entry 166 here.

Most helpful info yet. Thanks.