What would you have done (and bonus if you're familiar with citabrias)

[MauleSkinner]

I've noticed over the years that a lack of clear communication between the pilot and mechanic is far more common than we would prefer to believe. According to the mechanics I've worked with, "inop", "broke", and similar words do not exist except in a structural sense (the wing broke in half). If you are referring to the operation of a system, it's not "inop". It's either doing things that it's not supposed to or not doing something that it is supposed to. Either way, there are specific indications of such that need to be conveyed.

In the specific case of this Citabria, the original squawk, way back when, was probably just a mention to the mechanic on the way out the door that the struts seems to be vibrating once in a while. Nothing specific, nothing urgent, just a passing mention. It then becomes a non-urgent condition in the mind of the mechanic.

A more appropriate method would probably be a written squawk, outlining specifically the speeds and/or conditions under which the right rear strut vibrates (and that none of the others do), and whether or not you can hear it or feel it in the cockpit when it happens. Follow-up with the mechanic to ensure he got all the information he needed and/or how it was handled is usually a good idea.

If the mechanic doesn't see the need to deal with it, then other avenues need to be pursued. As I indicated in an earlier post, it's easier to apply the pressure to get something done if you're the one directly paying the bills. Rental airplanes need to be handled differently, and other than simply going elsewhere, I haven't found a technique that works consistently.

Note that this is all from the perspective of a pilot, not a mechanic. Commentary from the mechanics' side is welcome.

Fly safe!

David

 

[Rally]

Point taken Avbug you know your stuff. My communication might not have been the best. What I was suggesting is that alot of these aircraft are older, alot of annuals a minimal at best. I have seen it first hand, and refused to fly many aircraft. I once worked for a banner tow out fit that had significant play on the strut to wing attachment in otherwords you could see it move. I said thanks but no thanks. Fix it and call me when you want me to fly. The particular aircraft was a '43. Not to say that this could'nt happen on a 5 year old aircraft but if maintenance is not kept up over the years its all the more likely.

Has nothing to do with the age of the owner, pilot etc. There is quite a curve on age so to speak. When my father was a pilot at 30 a cub may have only been say 30 years old. Now its more than twice that, and you can have a perfect aircraft if maintained properly. But age, use, maintenance have to to be resonable to each other or crap breaks. Sorry for the miscommunication but I was mostly agreeing with your original statement in a not so smooth relavant way.

 

[Rally]

Was this a strut brace or the complete rear strut. For instance on a but there is actually 4 places where something attaches to the wing. Forward strut, rear strut and the two strut braces in between. Which was it?

 

[Immelman]

Thanks for the replies. Would have written back sooner but was away from the computer for several days.

First, thanks to all for the thoughts. Avbug, I appreciate the seriousness you gave to the issue. You had better believe that the first thing we did was to slow the airplane down in case of any bumps to reduce loading, and babied the airplane to the nearest field. The field repair was, in my opinion, **at the time** just fine, but I understand where you're coming from and recognize why we use 'AN' bolts, etc., to begin with. I'm still going over this in my head and recognize that, given all that is on the line, deciding to go home was probably a judgement error.

This particular airplane is only a few years old and has just a few hundred hours on it. Of course it is a metal wing spar being newer, not that that has anything to do with the rigging issue that might have caused that. Along those lines, I've learned that this airplane was ground looped with moderate damage and repaired by what is supposedly a reputable shop very experienced with citabria restoration (this was prior to the FBO purchasing it for rental use); from what I've gathered at least some rigging had to be done given the nature of the repairs. This may have been where the sort of vibration issue came from, unless Champion is producing aircraft this way (which I kind of doubt).

About that last question: No, the rear strut did not detach at any point. On citabrias there is a 4-pt brace made of three rods; two vertical that go from different points along the chord line of a single wing rib vertically down; they each attach to one strut (front and rear). There is a third rod, horizontal, that ties both vertical rods and both struts together. The connection points involve a vertical bolt that goes through each strut with a small, what I'd call as a layman "tack weld" to a horizontal (perpendicular) threaded piece above it; a conventional bolt screws into this horizonatally, and passes through each of the two rods that connect to an individual strut. The tack weld is what broke. This photo I found illustrates the structure I'm referring to:
http://www.planecover.com/Citabria/Citabria3.jpg

Notice the trapezoidal shape formed by the bracing I'm describing. Where that meets the rear strut was the point of failure. With the pressure relieved the bracing assembly separated from the strut by approx 1/2" in flight, and the distance was the same on the ground. They could be easily pushed back into the correct position (as was done to affix the temporary bracket).

Finally, I did write up a squawk describing the vibration including the speeds that excited it.

 

[Rally]

A worry but hardly as much as we made out of it in this conversation. I thought ther rear spar attachment strut is what had failed. Sorry. However it probably was not a approved repair and probably should have been on a ferry permit at least with a ferriable repair.

Thanks

 

[avbug]

I knew what you were talking about from your prior description, and I stand by my previous comments. Bottom line; if the repair isn't an authorized and approved repair, it makes the aircraft unairworthy. Without the repair, the aircraft is unairworthy. Taking guesses as to w(h)eather it's safe or not is irrelevant. Once the aircraft has been made unairworthy, all other discussions are meaningless, because that's as far as you need to go. Or should go.

The unairworthy condition is exactly worthy of the discussion in this thread; no one has made much ado about nothing.