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Yesterday was a terrible day for me and my waiex. Could really use some solid advice here from folks that know more than me. Have airframe and jabiru engine issues to sort.

So went to a fly in yesterday, and was aware of a storm drain grate in the middle of a taxiway from the hangars to the runway. Just wasn’t aware that there was two of them... went to leave and while taxiing out, the tailwheel fell into the grate, got caught and the force snapped it off.

The whole assembly was wore out to start with, and back in mid March I ordered a entire assembly new from Peter Anson out of Australia. It’s still sitting at the post office in Australia now, for coming up on 2 months.

The assembly snapped off where the steal portion that slides onto the tail spring, is welded to the steal portion the tail fork pivots on. The pivot bolt was also bent a little and the lower portion of the fork that the bolt goes through was all jacked up, although this tail wheel assembly catches on everything because it’s so low so this may have already been messed up to start with. The steering rod was also slightly bent.

We stopped the plane and got out and lifted the tail and walked it up to a friends hangar.

I used his mig welder and was able to weld the assembly back together. Probably and certainly not a world class weld but good enough I felt to get me home. Put in a new bolt for the pivot and actually, once all done the assembly was a lot tighter and less sloppy than it was before.

So then I reinstall it on the plane and more issues began to surface.

First off the tail wheel is no longer centered with the small rudder above it. When the wheel is centered the rudder was over quite a bit to the right. I could not remember it being this way before. That got me to looking closer at the ( I’m guessing titanium spring rod ) and how is it attached to the plane.... then I see where it looks like the rod itself may be slightly pulled out of the steel assembly bolted to the inside of the rudder hinge area / rear of the plane.

I have no idea since I didn’t build the plane or get plans with it, how that rod is secured. But there is a line visible on the rod where it looks like it might have been further up in that steel mounting assembly.

Then when I look at the steel assembly, it looks like it might be slightly pulled back and or bent upwards as well. There is a piece of paint missing on that piece just above where it appears to be deformed.

I don’t know how that part is supposed to look.

I also don’t know how you would remove it to replace it or service it. I see quite a few bolts holding it on, but if there is normal nylock nuts on the inside of the plane, I don’t know how you could get in there and hold them from turning.


We decided to make a new steering rod, because the one on the plane was non adjustable. We were able to make one that centered the wheel with the rudder.

I taxi the plane out to the runway, took off and flew back to my airport and taxi back to my hangar no problem. And handling wise it seemed just fine.


So then the next issue crops up.

While in the pattern to land at my airport, when I reduced the power to idle as I am turning base, the engine starts to lose power and I had the notion it might flame out if I didn’t add some throttle. Did it again after turning final so was keeping a little power in till I knew I had the runway made. Once I landed and was slowed to where I could u turn and back taxi to my hangar, the engine surged again and acted like it was going to die.

Parked in front of the hangar and it was surging at idle and very low throttle opening. Got out my phone and video it and it actually died while recording the video. It acted like it was running out of gas...

I double checked my fuel level , was nearly full, and removed the gas cap ( to rule out a blockage of the tanks venting system ) and hopped back in to restart and it had no effect the surging and wanting to die was only getting worse.

Leaning the mixture or going full rich had no effect either.

Any ideas? It’s a jabiru 3300 with a aeroinjector.

I did take some pics of the fuel filter and see it hasn’t been changed since 2016. If I had to take a guess I would guess it might be clogged up and causing a loss of fuel pressure to the aeroinjector. But was weird that in flight there was no power or running issues till I throttled back down to idle. But while on the ground in front of my hangar it seemed to be wanting to die even with the throttle opened up partly.

Anyways. I hate this crap. I don’t mind tinkering on the plane some but hate chasing issues and being responsible for fixing things I am not sure of the problem that’s causing the issue. So I turn to your folks for help!

I posted this on the sonex Facebook page as well with likely better pictures and video.

This forum is messing up the pictures!

Pics are sideways or upside down

Tried to load video of the engine running poorly but it won’t load

Skin on rudder above rudder horn seems like its is buckled slightly

Fuel filter, where would I be able to get a replacement

I hate to say it, but I think disassembly of the tail post may be in order, or at the very least, replacement of the welded fitment for the the tailwheel in the tailpost. It's not an impossible task but it's not an easy one either. This service bulletin may be helpful in showing you how those parts are connected:

https://www.sonexaircraft.com/files/pdf ... rawing.pdf

The tail wheel mount is attached in 2 places. #1 at the aft of the tail post where you can see it bent outwards, and #2 at another angle inside the fuselage. If the post was forced aft, there is probably damage at that angle inside the tail at #2 as well.





I'm really sorry that this happened. It must have been a heck of a jolt in the cockpit.

gyroron wrote:Skin on rudder above rudder horn seems like its is buckled slightly

I'm trying to imagine if that skin buckling is related to this incident. If the tailwheel steering pushrod was also pulled aft with significant force, I could imagine the stub-rudder being forced to full deflection to the right and beyond, which "might" have put stress in that area of the rudder but it's hard to say for sure.

Can’t help with tw assembly however the jab issue sounds like the fuel filter needs changing or replaced. You may not find the exact one so your plumbing may have to be changed. I have a cleanable filter from summit racing with a wire disk to strain the fuel. I clean it at least once a yr or any time I have it off. I would also look at the plugs they may be fouled out.
Mark