Stabilizer Streamline Strut Vibrations

[Battson]

We first encountered the issues with smaller tires fitted, Goodyear "26s" (which are really 23 inches tall)

[Craig Van Sickle]

I've searched and can't find the thread that covers your strut break and engineering change. Do you have a link?

[Craig Van Sickle]

I wonder if big tires throw more turbulence back to the tail?

[Battson]

I have also had issues with the streamlined flying wires hitting resonance, they vibrate a lot and you will never know unless you look back when the elevator is unloaded (hands free). You can change the resonant frequency by changing the tension in the wires (I suggest lower, not higher).

[Battson]

Mine also broke in flight, there is a different post about that plus and engineering change which fixed the issue.

The beauty of the design is the tail system has redundancy, so wires or struts failing is not a problem.

[jaredyates]

I would love for someone to put together a Beartracks article about it.

[jaredyates]

I think mine broke because of corrosion rather than resonance

[Wyo Johnson]

Correct me if I'm wrong, but I remember some time ago Jared caught an issue during an inspection/preflight on this tail strut? I did a search but didn't find the thread, just wondering out loud if this is related?

Higher time and/or bush fliers seeing any issues?

Andy

[svyolo]

This thread might be important enough safety-wise to put somewhere that all builders see it at some point. Maybe a Beartracks article? Sticky in one of the forum categories, like the current one?

[Mark Goldberg]

While I have no knowledge about this and no expertise - I kind of suspect just one strip in the middle might break up the harmonic vibration. But someone would need to try. Mark

[Steve W]

Nev, I think you are referring to the 4 place. The Patrol strut is formed and drilled at each end so no threads.

Mark, Mike Silvernagle mentioned making 6 strips so that's what I used pr side. He may have only added three a side. Unclear on that whether he attached the six to the one strut that was vibrating or three to each.

Mike wrote:
" I ended up cutting 6 pieces of 1/4" wide strips of velcro 1" long and sticking them to the underside of the 4130 streamlined tubing"

If the weather was warmer and I had the opportunity to play with the strips, I'd see what the minimum would be to eliminate the vibration.

Thanks for the feed back guys.

[Mark Goldberg]

Thanks for posting this Steve. You put more velcro strips than I imagined. I wonder if fewer strips would accomplish the same thing? Maybe someone will play with it and answer this question. Mark

[Nev]

Good to see you got it sorted. I was wondering if that could be the cause of fatigue issues on the threaded portion inboard, if the vibration is left to continue.

[Steve W]

Picture of the velcro strips used to stop vibration

[Steve W]

Sure will Mark. It will be a while. The plane is an hour away and will be sometime before I’m up there again unless the weather warms up.