Broken Dorsal Fin forward attach point
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- learaviator
- Posts: 174
- Joined: Wed Dec 31, 2008 5:20 pm
Broken Dorsal Fin forward attach point
Well, it would appear that over the years too many people pushed on the fin to move this plane. While doing the annual I noticed that the front of the fin had a little play side to side. After checking the bolt and screw and tightening both nothing changed so I pulled the fin and found the attach point completely broke off. Good time to install my BAS tail pull handle kit I bought. Has anyone had to address this? Did you replace the entire channel? Also finished converting the wing root fairings to screws. Pain in the rear..... Also installed the STC'd cowl latches. I know one of these days I get to fly it!
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"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
- GAHorn
- Posts: 21302
- Joined: Fri Apr 12, 2002 8:45 pm
Re: Broken Dorsal Fin forward attach point
PN 0531112-4, (item 31 in Fig 13 of the B-model IPC) is rivetted to the dorsal on both sides. (two bracketts for each airplane). It looks like replacing the bracketts only is the thing to do. You can even make these bracketts under the owner-produced rule.
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'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- learaviator
- Posts: 174
- Joined: Wed Dec 31, 2008 5:20 pm
Re: Broken Dorsal Fin forward attach point
Hi George, actually this is a A model so it has the single attach point underneath the fin. Talked with a friend in the FAA and I think we have figured out a fix without having to replace the entire channel. We will see.....
"You can only tie the record for flying low"
1950 170A N9907A 180hp. STOL
1950 170A N9907A 180hp. STOL
- GAHorn
- Posts: 21302
- Joined: Fri Apr 12, 2002 8:45 pm
Re: Broken Dorsal Fin forward attach point
Well, DOH! I could have/should have noticed that from the pic and the signature!learaviator wrote:Hi George, actually this is a A model so it has the single attach point underneath the fin. Talked with a friend in the FAA and I think we have figured out a fix without having to replace the entire channel. We will see.....
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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