Thanks for the pic of the broken piece----guess there is a good reason to inspect. Is that a crack in the radius of the flat top piece ahead of the hinge bracket?

180Marty wrote:Thanks for the pic of the broken piece----guess there is a good reason to inspect. Is that a crack in the radius of the flat top piece ahead of the hinge bracket?

I was wondering the same Marty. Looks like a crack to me.

Good find on that C-180 “hockey stick” stringer.
It was certainly time to take that tail section apart for inspection.
I have found them cracked before, but not broken.
That stringer extends forward along the fuselage for about 3 ft.
In ground handing, pushing, swinging the tail ...if someone pushs hard on the horizontal stab instead of the fuselage, you will sometimes see a wrinkle on the fuselage along that stringer. It sometimes happened when operating on skis or pushing with unknowlegeable help. I suppose that rear fitting could crack too. Installing and using the retractable tail handles is a good upgrade.
Those 2015 Cessna prices are crazy. Somewhere on file I have a receipt from 20 years ago ... thinking it might of been $250.

Yes, things are crazy expensive. And yes, that is a crack in the top shelf P/N 712206-0:



The good news is it’s going to be very easy to rig the jackscrews. The bad news is I’ve got a lot riveting to do. I’m going to pull the plane out and pressure wash the tailcone to see if there are more surprises out there.

Can the hockey puck be spliced a little ahead of the crack to save replacing the whole thing? There is some pretty thick metal back in that area

I think any repair patch would have to go well past the bead/groove. Problematic with a flat sheet on the top surface as it would have to pick up the hinge support bracket, located to the right. An undersurface patch would avoid that, but would require cutting up a shelf part in order to have a pressed bead/groove to fit under the existing one. That might work, but I already have to replace nearly half the rivets on the shelf, and any such patch repair wouldn’t be a standard AC43.13-1b - Acceptable Methods - Repair patch and subject to the whims of any AI or FAA dude or dudette. We’ll see what my IA says.

Jrc, is that a stop drill hole there? If so, I wonder how long it's actually been cracked.

A1Skinner, nosir, it sorta kind of looks a little like one from that angle but on close inspection, not stop drilled. On the other hand, the broken off piece, has been that way for a long tme, no shiny metal at all.

I just took a peek at mine since it has been awhile. Pretty easy if you trim for full nose down and pull the fairing on the underside of the horizontal stabilizer. Can just about see the bushing that is the pivot point from the opposite side looking through the big hole. What would be really good is to get an inspection camera deal that you can see with your android phone or borescope. In looking at it, the angle is straight for the back foot or more and looks like it could be spliced----maybe by the big hole on top cover piece. I happen to have a new rear bulkhead that shows where the rear of the hockey stick is riveted----about where the 5 is located.

180Marty, I initially thought that perhaps you could cut the damaged end after 4 or so rivets in a straight line and replace that damaged portion with the servicable portion, and then overly that junction with 8 rivets from the remainder of the straight servicable channel. After review AC43.13 part b for stringer/flange repairs, it appears way more complicated than that. I’ll see if I can get a call into Cessna Engineering on Monday to see if they have any authorized repairs.

Thx, Ron

Something like that----maybe 4 to 6 inches from the back. I'd talk to a real mechanic and see what is legal. Think about how the wing spar is a splice where the strut attaches. Maybe in addition, an aluminum or stainless strap could go on the top side of the top cover plate for extra reinforcement at the splice since the horizontal still has a gap when full up trim is used.

That photo of the circled crack on the top shelf that jrc111 posted above ...
FWIW, I believe that crack is not uncommon.
When I purchased my 180 almost 40 years ago, one of the first inspections I completed was removal of the tail section. I had that same crack in the same location, it was stop drilled. I have kept an eye on it, it has not advanced.
Also, I have noticed the same crack, stop drilled on other early model C-180.

Good to know, 54c180. I spoke with Brandon, a Cessna Structures Engineer, and he said he couldn’t see any authorized repair. So, down the rabbit hole I go.

Fabbed a cradle:



Mounted it on a boat jack:



Top shelf off:



Even after pressure washing, there’s a lot of gritty, oily residue there. More cleanup needed. Even though there’s an undocumented bottom access hole/cover in the jackscrew compartment, similar to the wing access holes, there’s no doubler on it. I’ll never have better access to that compartment, so I’m probably going to install the SK185-27 Tail Cone Access Panel Service Kit.

Please keep the pictures coming----like seeing all you're doing. When you get a new hockey stick, could you take a pic of the back end? I have the jackscrew access panel but never got nerve enough the start cutting metal to install. Thanks

I went ahead with the SK185-27 Tail Cone Access Panel Service Kit. My aircraft is more difficult, because of the access hole previously placed and because apparently rivnuts had been placed twice. In order to cover the rivnut holes, it was necessary to fabricate a slightly enlarged cover plate and use countersunk rivets on the forward rivet line. The instructions describe how to install this kit from the bottom, but it’s much easier with the stabilizer out, and especially with the “top shelf” out.

Initial hole:



Best fit of doubler:



The instructions describe marking out the edge of the “stock” cover and then cutting it out:



Marked skin, cutting the radius corners with a unibit:



Making the cutout with a Dremel wheel:



Smoothed cutout, countersunk forward rivet line (skin 0.050” thick):

Where did you get the SK185-27 kit? Whenever I’ve looked they’ve been huge $, used parts, or both.

For kicks I looked at my 185-27 that I paid $104 21 years ago and still haven't installed. Also, the bushings on the bottom of the jackscrews. I'm curious too what the kit costs today.

I bought mine in 2016 for $665; price now is $750.

Received the salvage “hockystick” and tailcone “top shelf” yesterday from BAS Sales; both serviceable and fairly close fit to existing structure,should fit. Here’s a picture of the hockeystick aft end for 180Marty:



Finished the Tailcone Access Cover service kit, except for paint:

Finished preparing the McFarlane jackscrews for installation. First, greased the new jackscrews:



Theres a chain guard, spring retaining flange and backing plate to remove. Next, removed the chain roll pin and sprocket:





Removed old bearing (the old jackscrew just slides out):



Socket and scrap tubing used to install new jackscrew and bearing:



I attempted to use McFarlane’s roll pin removal and installation tool, but it broke:



A crowsfoot socket can support the sprocket when installing the roll pin (which is safetied after install) to avoid buggering the bearing:



After installing the spring flange and backing plate as well replacing the boot, the jackscrew is tightened all the way down, I used super weatherstrip cement to seal the boots: