A variety of items are cropping up that need attention:
ARIN-429 module, rough running at start up, worn nose tire, relocate headset jacks for pilot/copilot. Found some cracks in baffling - details here: https://cozy1537.blogspot.com/2023/11/baffling-cracks.html
Recently the ARINC429 module was replaced but it seems the transponder was contributing to it going off line. The coax and connectors for the transponder appear to be good and check good with a meter. I don't have the TNC adapter to connect to the NanoVNA to see what that looks like though. There is a BNC connector on the antenna that the Nano will connect to. Some ferrite beads will be installed on the cables near the antenna to further reduce any stray noise. Also suspect the annular slot antenna needs a better ground plane. During Phase I, there was ballast piled around the front of the nose and it has all been moved into the nose.
Thursday evening, Dynon had sent an email alerting of a safety of flight issue with the Auto Pilot panel made 2017 and earlier. I powered the display up, went into network mode to get the serial number and found it was not an affected unit.
One of the safety pilots works with avionics a lot and recommended I start the engine with the avionics off, turn on the alternator field, then power up the avionics. He said that modern avionics are supposed to handle the voltage fluctuations, but after starting the engine, the current and voltages can spike quite a bit. The downside to doing this is that I cant read my fuel pressure or oil pressure when the engine starts. I suppose I could boot one display, turn on the fuel pump, then turn the display off while starting. I'll consult with Dynon support. It may be with the back up batteries for the displays, they'll help filter the power so may not be an issue.
On Friday morning when starting the engine for the 4th formation flight, the fuel pressure was reading 80 lbs. I told the safety pilot this wasn't normal so we climbed into his RV7 to do the flight. Saturday, I pulled the cowls and battery cover. The ground at the battery was slightly loose and also the positive on the master was slightly loose. Some of the smaller ground wire screws on a terminal strip in the hell hole took about 1/8 turn. A test run was good and the cowls were put back on. I taxied over to the self serve fuel and returned without trouble, shut down and later came back, restarted and the engine was loping and missing terribly. I pulled the cowls off again, borrowed a spark plug wrench and looked at the top #2 plug. It looked like it had been pretty wet so suspect the plugs weren't pristine, engine is running a bit rich at lower power settings doing formation flights. I put the plug back in, did a full power run long enough that the oil had warmed to 200. It was running fine. I consulted with several folks about whether it was safe to fly home and I felt it was.
The nose wheel tire tread has worn down quite a bit on this trip so will probably put a new tire on that is setting on the shelf. I need to fix the foot on the nose gear too, it's been bent since before OSH when I landed with the gear not completely down. Mine takes 20 seconds to lower, so the gear needs to come down when entering downwind, not base/final....
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| The "new" tire that's been setting on the shelf awhile. |
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| The old Kenda tire. |
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| Fuel filter debris at 150 TT, 70 hours since cleaned last. |
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| The Kenda tire with about 170 landings. |
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