U-Bolt Failure

[N8293A]

I promised Jim more info about my KOSH trip. The below part broke as I was parking the airplane. As I pulled up to my tie down I felt a slight drop in the tail, almost as though the tail wheel had sunk in a depression in the grass. I didn't think anything of it, and went on about my day enjoying all there is to see at AirVenture. Upon returning to the airplane that afternoon, I was accosted by three fellow TIC170A members. Brad McGaw, Wayne Eberhart, and Dave Finamore, they had been waiting for me to get back to the airplane to alert me to a problem. While looking over my airplane they noticed the broken U-bolt. I am confident I would have seen it on preflight the next morning, but I sure appreciated being warned ahead of time. The TIC170A family comes through again! OK, now what to do! Well Dave Finamore says "hey I'm not leaving till Friday, take the U-bolt off my plane, get home, and get it back to me before Friday." Wow, what an offer to make. So with Dave, Joe Persinger, a friend of Joe's, (and a local A&P to oversee our work;) we got Daves airplane lifted onto a cooler to scavange the part. We did the same with mine, and got it installed. I flew home and talked to my IA who inspected the broken bolt, and speculated it had been partially compromised for a while. The side that broke showed corrosion about 1/3 of the way through the threaded area. Not to mention, how distorted it was. My IA then got on the phone to find a replacement, the quote he got from a Cessna dealer, who shall not be named, was $2000.00!!! That's not a typo. Fortunately we then contacted Air Repair, and I'm getting a new U-bolt and stiffener for a much more reasonable price. I got in my car and drove back to KOSH with Dave's U-bolt and by 5:30 PM we had everything put back together. Thanks to all involved. The generosity, concern, and depth of knowledge of the TIC170A family is well represented in this example, and we got to see it many times at this years convention also. See what you missed Jim! Thanks again to all involved.

[cessna170bdriver]

Steve,

I know where there's a serviceable one in St. Louis. Only problem is it has tan paint on it.

[N8293A]

Miles, I knew you were going to say that!

[mit]

There are alot that have a 2 pieces of steel and two a AN Bolts...

[piclr60]

Hey Steve,

Did the part fit? You mentioned that they had two sizes and you had them send the smaller one. Did you guess correctly?

Brad

[N8293A]

Brad the part from Air Repair fit perfectly. Things went together better in the hangar than they did in the field. Thanks for your help, by the way. I bought the U-bolt, the stiffener, two new nuts, and while I was messing around down there, a new chain guard for the lower bracket. The total cost was around $93.00 I think. Sure beats $2000.00 from Cessna.

[flyguy]

- - Sure beats $2000.00 from Cessna.

They have little interest in supplying parts - even a two dollar u-bolt for our classic airplanes. That little piece couldn't possibly have cost them over $.50 and they only price it out of reason so they don't have to mess with us. If you had a Citation or a Caravan that needed a $5000.00 part then you might get consideration.

[DaveF]

The L-19 U-bolt is taller because the L-19 tail bracket is taller than the 170 bracket. Here are some L-19 pics I took at OSH. Note that the bracket doesn't get shorter at the end, nor does it secure the tail of the channel, as it does on the 170. In fact, I'm not even sure why there is a U-bolt on the L-19.

[Bruce Fenstermacher]

Dave, I think the L-19 brackets you show are modified or since they appear the same, a later version. I think a later version.

The point is not all L-19 brackets look like those you show. I have and many others have L-19 brackets that are the exact same as the 170 and the U-bolt is therefor the same. The key is getting the same part.

I like your pictures though because it shows that perhaps many 170 brackets could be modified to the L-19 type you show after the tang cracks of the top bracket.

[GAHorn]

This difference is reflected in the change from the O1 to the O1A (L-19/L19A and subsequents).