The Cessna 120-140 Association Forum

Earlier this summer I was taxiing off road and noticed quite a bit of sway in my cabin. I have it recorded on video. I know a V-Brace is a common upgrade for the 170/180/185, but I have not seen anything documented for the 120/140. In a little bit of research with other 120 owners, it looks like Michael Sibley of Alaska made (or still makes?) a V-Brace for the C150, we are thinking that might directly bolt onto our 120/140s. Unfortunately I haven’t been able to find current contact information for Mr Sibley.

Anyone have contact with him? Or know of a V-Brace design for the 120/140? Any other relevant thoughts?

Thanks,

Video for those who are curious:
https://youtu.be/IMbISUCD7xo

I think the float plane kit for our birds has a V brace.
https://m.youtube.com/watch?v=fyVgg62d18Q

I hear they are hard to find but maybe you could make an owner produced part if you can get the dimensions from someone who has one.

Keep posting those videos!!

8359 wrote: ↑Mon Dec 09, 2019 8:55 pm Video for those who are curious:
https://youtu.be/IMbISUCD7xo

Just a suggestion -- you may want to carefully look and "feel" in the areas of what appears to be obvious movement while having someone rock the wings. There's a possibility of some loose (or, sheared?) rivets allowing what may be excessive movement of rigidly attached parts. Mac

Could the movement you are seeing in the video be an artifact of the electronic stabilization in the camera?

Thanks for the suggestions. I haven’t been able to find anything about the factory float kit including a V brace. If anyone has any info about it it would be greatly appreciated.

I’ll try the wing rock trick, but the airplane was restored in 2015, stripped down to the frame, not saying it’s impossible, but I have good confidence most of it is in great shape.

The factory float kit did not have that brace. If I were looking of one, I'd contact Wiley's seaplane base in Lake Oswego, Oregon. They have several STCs for Cessna float planes and could probably point you in the right direction.

Hard to tell from the video if that's normal or not. They do flex quite a bit. As suggested, check for sheared rivets at the top and bottom of the door posts and where they are riveted to the (structural) instrument panel.

Thanks for the suggestion John. I called up and the gentleman who answered said his father was the one who would have known, but he passed. His son only manages the property but doesn't know anything about airplanes.

I'll keep searching around. Might just have to call up some tail numbers from people who I see have them in photos.

8359 wrote: ↑Thu Dec 12, 2019 2:47 pm his father was the one who would have known, but he passed.

I wonder what has happened with the STCs? His father was Dave Wiley. Ironically, he died in a float plane accident a while back. HE also had an STC for a Dorsal fin on a 120/140.

I just did a quick search. There are 26 STCs assigned to Wiley's Seaplane Base. None for a V-brace, though.

Thanks for digging into it. I wonder if his son is also managing those.

I was able to get a hold of Mike Sibley in Alaska. He makes one for the 150 that he said is compatible with the 120/140. I guess he just sold one to a 140 owner in GA. He said his design is a little better than the "original" because it ties into the motor mount and moves the brace further way from the occupants, so you don't bang your head against it in a wreck.

Thanks for the help John.