Smoking rivets - Cessna strut

saddletramp

saddletramp

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saddletramp
My straight tail 182 is in for an annual. I stopped by today for an update & the head mechanic at the shop said he was a bit concerned about my right strut. At the top of the strut near the wing are four large flat rivets. The are flush with the strut. The top rivet had about 1/2" of trailing smoke around it. The second rivet down had some darkening around it too.

We decided to clean the rivets, fly the airplane a bit, & see if the smoking continues.

I'm sure a new strut from Cessna would be very costly. I'm hoping we're not headed there.

My airframe has around 4,600 hours on it.
 
Smoking rivets don’t stop. Sorry yours are in a kinda expensive spot, but they don’t usually get better.

We have a couple on the tail and one on the cowl. We’re about 1000 hours “newer” than your airplane, though.
 
I checked on Backcountry pilot & there was a 180 owner that had the same issue & had the strut inspected & the rivets were replaced. It sounded like they were very hard rivets & had to be pressed into place hydraulically. That sound cheaper than strut replacement.

I'm also having them perform the Cessna service bulletin concerning cracking in the tail. Today they were removing my tail feathers to check that too. Since I have the "jackscrew" style trim I requested they service & lube the jackscrew trim assembly too.

Just as we were starting to show a little profit in our glider operation the annual will eat that all that money up! I'm glad I have some cash reserve put away!
 
My guess is they are probably regular AD rivets, I'm curious if they pass all the way thru and are double flush. If so then a guy really needs a shaver in addition to appropriate riveting tools.
 
The thread on BCP ended up being a debate on rivet types. It appears these are DD rivets.
 
salvage yard.
 
DD are hard but not super hard. Big airplanes use lots of them, I’ve driven plenty of -6 ones, no big deal.
Rivet smoking is a loose rivet.
 
Cessna has an SID (Supplemental Inspection Document) on it. Someday, after a crash or two, it will be an AD. They recommend an eddy-current inspection of the struts around those rivets, since they have had reports of cracking there. We found one like that on a 180; the crack was invisible but it was there. The countersunk rivet places an outward force on the hole, and lift loads do the rest. Any crack, invisible or not, is a failure in progress, and as it crack it places more stress on the remaining rivets and the surrounding strut material, raising the possibility of more cracks and eventual failure.

A smoking rivet there would concern me. I'd be getting it checked properly. And another question: has the tiedown ring been left off? It's part of that structure, too. It's in shear just like the rivets.

I know, I know, Cessnas aren't falling out of the sky as their struts and wings fall off.

Not yet. But you younger guys don't have arthritis yet, either. You quite possibly will as you get older. Age and activity weaken bodies and airplanes.
 
Dan Thomas said:
Not without Cessna's approval. That removes critical material from the lift lug. Cessna might not have much to say about ELT mounts, but they sure would say something about strut mods.
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Like I said earlier,, Salvage yards strut is the easy fix.

Jo-bolt is an acceptable substitute for a rivet. and does not meet the requirements of 43-A for a major repair.------ No I would not do it. too easy to get another strut.
 
Tom-D said:
Like I said earlier,, Salvage yards strut is the easy fix.

Jo-bolt is an acceptable substitute for a rivet. and does not meet the requirements of 43-A for a major repair.------ No I would not do it. too easy to get another strut.
Click to expand...

Have you ever used a jo-bolt? Its not the same as a hi-lok either.

I can honestly say I have, they are used all over thrust reversers on Cessnas.
 
Wing struts are primary structure. If rivets are smoking in primary structure, there are issues. Ignoring this in an old aircraft that is possibly used to tow gliders is asking for trouble. A broomtail 182 is neat, but it is an old bird.
 
Dan Thomas said:
Not without Cessna's approval. That removes critical material from the lift lug. Cessna might not have much to say about ELT mounts, but they sure would say something about strut mods.
Click to expand...

Yep.

Tom-D said:
Like I said earlier,, Salvage yards strut is the easy fix.

Jo-bolt is an acceptable substitute for a rivet. and does not meet the requirements of 43-A for a major repair.------ No I would not do it. too easy to get another strut.
Click to expand...

Nope
 
Tom-D said:
And most likely an elongated hole.
Repair? Ream it to the next oversized and replace it with a High-lock/Jo-Bolt.

https://catalog.monroeaerospace.com/viewitems/all-categories/jo-bolts-1
Click to expand...
Hi Loks are great. But the hole needs to be dead nuts straight and reamed to the proper size. I worked the X47B prototype and we had to sell each and every hole. Nothing but hi shears, hi loks.
May be able to go first or second oversized hi lol instead of a full rivet size.
Cessna engineering must be consulted of course.
 
Tom-D said:
Jo-bolt is an acceptable substitute for a rivet.
Click to expand...

Do you just make this stuff up? There is nothing in the Cessna SRM that would permit a Jo-Bolt (NAS1670 or NAS1750) to be an acceptable substitute for a rivet.
 
In my career in aviation starting in 1978 working the major airlines and military contracts as well as general aviation I have never had the occasion to use a jo bolt. Do they require a special tool?
 
JAWS said:
Yep. Nope
Click to expand...
FAR 43-A
(a) Major alterations—(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:

(i) Wings.

(ii) Tail surfaces.

(iii) Fuselage.

(iv) Engine mounts.

(v) Control system.

(vi) Landing gear.

(vii) Hull or floats.

(viii) Elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights.

(ix) Hydraulic and electrical actuating system of components.

(x) Rotor blades.

(xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft.

(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.

(xiii) Changes to the wing or to fixed or movable control surfaces which affect flutter and vibration characteristics.
Show me where changing a fastener meets the requirement of Appendix A
 
bnt83 said:
IOW you have never used either.
Click to expand...
Jo-bolts and hi-loc fasteners are mostly used in heavy aircraft, not Cessnas, but I did work 22 years on military aircraft plus 8 as a contractor that use plenty of them. No I don't now use them, I have neither the tools and equipment to put one in. So it's not that I don't know what they are or how to use them.
 
Tom-D said:
Jo-bolts and hi-loc fasteners are mostly used in heavy aircraft, not Cessnas
Click to expand...

Cessna 310s, and I’m pretty sure all other twin Cessnas, use hundreds of Hi-loks. Specifically, to attach the spar cap to the spar web.
 
slacktide said:
Cessna 310s, and I’m pretty sure all other twin Cessnas, use hundreds of Hi-loks. Specifically, to attach the spar cap to the spar web.
Click to expand...
That's great, I don't work the Cessna twins.
Didn't know they had struts
 
Tom-D said:
FAR 43-A
(a) Major alterations—(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:

(i) Wings.

(ii) Tail surfaces.

(iii) Fuselage.

(iv) Engine mounts.

(v) Control system.

(vi) Landing gear.

(vii) Hull or floats.

(viii) Elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights.

(ix) Hydraulic and electrical actuating system of components.

(x) Rotor blades.

(xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft.

(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.

(xiii) Changes to the wing or to fixed or movable control surfaces which affect flutter and vibration characteristics.
Show me where changing a fastener meets the requirement of Appendix A
Click to expand...

Who said this would be an alteration? :confused:

Tom-D said:
Jo-bolt is an acceptable substitute for a rivet. and does not meet the requirements of 43-A for a major repair.
Click to expand...
 
Tom-D said:
That's great, I don't work the Cessna twins. Didn't know they had struts
Click to expand...

Perhaps you should not comment on topics you don’t understand, in that case.

Cessna singles also use hi-loks. 206 on the wing attach fittings, post restart 172 on the landing gear bulkhead.
 
JAWS said:
Who said this would be an alteration? :confused:
Click to expand...
See anything here to cause a major repair?

(b) Major repairs—(1) Airframe major repairs. Repairs to the following parts of an airframe and repairs of the following types, involving the strengthening, reinforcing, splicing, and manufacturing of primary structural members or their replacement, when replacement is by fabrication such as riveting or welding, are airframe major repairs.

(i) Box beams.

(ii) Monocoque or semimonocoque wings or control surfaces.

(iii) Wing stringers or chord members.

(iv) Spars.

(v) Spar flanges.

(vi) Members of truss-type beams.

(vii) Thin sheet webs of beams.

(viii) Keel and chine members of boat hulls or floats.

(ix) Corrugated sheet compression members which act as flange material of wings or tail surfaces.

(x) Wing main ribs and compression members.

(xi) Wing or tail surface brace struts.

(xii) Engine mounts.

(xiii) Fuselage longerons.

(xiv) Members of the side truss, horizontal truss, or bulkheads.

(xv) Main seat support braces and brackets.

(xvi) Landing gear brace struts.

(xvii) Axles.

(xviii) Wheels.

(xix) Skis, and ski pedestals.

(xx) Parts of the control system such as control columns, pedals, shafts, brackets, or horns.

(xxi) Repairs involving the substitution of material.

(xxii) The repair of damaged areas in metal or plywood stressed covering exceeding six inches in any direction.

(xxiii) The repair of portions of skin sheets by making additional seams.

(xxiv) The splicing of skin sheets.

(xxv) The repair of three or more adjacent wing or control surface ribs or the leading edge of wings and control surfaces, between such adjacent ribs.

(xxvi) Repair of fabric covering involving an area greater than that required to repair two adjacent ribs.

(xxvii) Replacement of fabric on fabric covered parts such as wings, fuselages, stabilizers, and control surfaces.

(xxviii) Repairing, including rebottoming, of removable or integral fuel tanks and oil tanks.

Remember its just a fastener replacement.
 
slacktide said:
Perhaps you should not comment on topics you don’t understand, in that case.
Click to expand...
Re-read post #1, see what aircraft we were talking about prior to the thread creep. Then tell me how many Jo-bolts And or Hi-Locs the 182 has?

If you like I can take pictures of a 182 strut in the morning.
 
slacktide said:
Perhaps you should not comment on topics you don’t understand, in that case.

Cessna singles also use hi-loks. 206 on the wing attach fittings, post restart 172 on the landing gear bulkhead.
Click to expand...
How did you make the connection between a 182 old enough to have loose rivets to a newer 206 or 172?
or are you really stretching the thread creep simply to make me look bad.
 
Tom-D said:
Re-read post #1, see what aircraft we were talking about prior to the thread creep. Then tell me how many Jo-bolts And or Hi-Locs the 182 has?
Click to expand...

You are the one who said that Jo-Bolts can legally substitue for rivets. They cannot.
 
Tom-D said:
How did you make the connection between a 182 old enough to have loose rivets to a newer 206 or 172?
or are you really stretching the thread creep simply to make me look bad.
Click to expand...

You are the one who said that Cessnas do not use Hi-Loks. They do.

Tom, you make yourself look bad. No one has to help you do that.
 
Tom-D said:
(b) Major repairs—(1) Airframe major repairs. Repairs to the following parts of an airframe and repairs of the following types, involving the strengthening, reinforcing, splicing, and manufacturing of primary structural members or their replacement, when replacement is by fabrication such as riveting or welding, are airframe major repairs.
Click to expand...
Tom-D said:
(xi) Wing or tail surface brace struts.
Click to expand...

Actually I can see it both ways. I would error on the cautious side and call it a major repair. Replacing the strut would be easier and faster and potentially cheaper. Difficult to say for sure without seeing the airplane in person.
 
slacktide said:
You are the one who said that Cessnas do not use Hi-Loks. They do.

Tom, you make yourself look bad. No one has to help you do that.
Click to expand...
you should do your home work, on the use of fasteners.
http://www.flight-mechanic.com/structural-fasteners-special-purpose-fasteners-blind-bolts/
There are various names these fasteners go by. The AC 43.13 chapter 7- gives a pretty good description of them.
No where in Cessna's manuals do they forbid their use.
Getting back to the subject, replacement of 1 or 2 fasteners does not constitute a major repair.
If you think I'm wrong quote your reference
 
slacktide said:
You tell me. You are the one who claimed it was true in post #11, and post #9 of this thread. The burden of proof lies upon those who make extraordinary claims.
Click to expand...
And I'll stick by those claims until you prove me wrong with a valid reference from Cessna.
Put up or shut up.

We see these high stress fasteners used every day in GA, They are known by several names, jo-bolt/hi-loc are just the most recognized, thus my use of the term.
 
Tom-D said:
No, no, no. You are not turning this on me, you claimed they could not be used.... Prove it.
Click to expand...

It does not work that way, and you know it. A subsitution for the part specified in the part catalog is only authorized if there is approved data to support it’s use. There is no approved data that allows a jo-bolt to substitute for a rivet. Cessna’s structural repair manual for single engine aircraft, chapter 51-40-00, table 1, lists approved rivet substitutions. None of them are jo-bolts.
 
slacktide said:
It does not work that way, and you know it. A subsitution for the part specified in the part catalog is only authorized if there is approved data to support it’s use. There is no approved data that allows a jo-bolt to substitute for a rivet. Cessna’s structural repair manual for single engine aircraft, chapter 51-40-00, table 1, lists approved rivet substitutions. None of them are jo-bolts.
Click to expand...
Same manual
page 51-40-00 page 1 para C
  1. Hi-Shear Rivets.
(1) When Hi-Shear rivets are not available, replacement of sizes 3/16 inch or greater rivets shall be

made with bolts of equal or greater strength than the rivet being replaced, and with self-locking nuts of the same diameter. It is permissible to replace Hi-Shear rivets with Hi-Lok bolts of the same material, diameter and grip length.

You should actually read.
 
nite nite now see ya
 
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