The Cessna 120-140 Association Forum

See attached photo ...
Does this make the aircraft unairworthy or is just not the recommended method of attaching the tailwheel bracket?

You are opening "the box" again!! If it's your airplane NO, but if it's someone else, Yes. I'll wait for the gurus to chime in and maybe come back.

In the recent months, I saw a picture of the TW assembly break down that showed the AN bolts with two washers inside but I haven't been able to find the article again. Almost looked like a parts manual picture excerpt. Thought possibly it was in a Neil Wright article.

In 70 odd year aircraft, sometimes it's best to let a "sleeping dog lie"! As long as it's not critical to structural safety.

PS With 36 AN bolts providing the "clamping force", do you think it may fall off?

It’s fine. Over the years those brackets crack in the top corners and drilling and reriveting takes its toll. Bolts are strong enough but the purest clan will poo poo it. It’s like the carry thru service kit that cessna put out saying you can use those big rivets but AN bolts were recommended to bolt carry thru to doorpost. FWIW ours is bolted on as well (on its 3rd bracket in its lifetime).
What I do have a problem is when bolts are run up the sides of the tail post bracket. Not much edge distance and many rivet holes to promote spiderweb cracks. I believe Lorraine? has a Facebook post with some good pics. If someone did that I (speaking only for myself) would just rebuild the whole tailcone. Not that hard to do.

Rivets do look better especially if you’re going for an Oshkosh grand champion. Just a question what is that doubler that’s riveted on above the bracket repairing.

As far as FAA 43.13-1B guidance on edge distance there is reference to rivets but really no guidance to bolts. Asking around and research on the internet seems to be the same 2x diameter for bolts too (with no definite chart or paragraph reference) curiosity has me digging into that more.

Thanks for opening “The Box” I’m sure this thread will turn into a Facebook plumbing or construction thread. Kidding Flame on!

Not my plane, but one that is for sale that I have been looking at

Technically............no, the tailwheel bracket should be riveted on.
As a general rule, bolts can replace rivets if they are 3/16's or larger. Usually it requires the manufactures approval. Would Textron issue a letter of "No objection"........maybe....... However For something like that, if you got Cessna Tech support on the line.......they'd probably just say..........."really, can't you rivet it?".

In a real world, I see about one out of about 10-15 airplanes has some sort of non standard application on that bracket. (I've seen -3 and -4 bolts ........I've also seen AN525 structural screws) In a real world, I don't recall one ever moving or falling off. So........all things considered were I doing a pre-buy on that airplane I would point it out, but wouldn't consider it a deal breaker.

Another item, is the forward steering chain attachment to the rudder horn. I see that eye bolt attach method regularly, unfortunately that brings the steering chain in at the wrong angle. (and tends to bend the rudder horn). The proper install is a small stamped "S" bracket that comes off the back of the rudder horn and keeps the steering chain a bit higher and closer to the center of the rudder horn.

The patch at the trailing edge of the stab on the bottom is extremely common. That skin cracks for one of several reasons.
A. the forward leaf spring bolt broke, the whole leaf spring (with tail wheel) falls off and beats the sXXt out of the bottom of the rudder and aft stab and sometimes elevator.
B. people pushing the aircraft by the horizontal and rudder will crack the forward and aft stab mounting areas
C. no vertical fin re-inforcement (per the AD) causes that area to flex
D. Some other reason I can't think of right now.

V529 wrote: ↑Wed Oct 16, 2024 8:30 pm they'd probably just say..........."really, can't you rivet it?"

Too late now!

6643 wrote: ↑Fri Oct 18, 2024 8:53 am

V529 wrote: ↑Wed Oct 16, 2024 8:30 pm they'd probably just say..........."really, can't you rivet it?"

Too late now!

Never too late.........

How about pulled rivets?

4004 wrote: ↑Sat Oct 19, 2024 12:35 pm How about pulled rivets?

You trying to start sumthin'
Least favorite option.........(for that application)........

Jo-bolts.