Magnetometer and AHARS Calibration

Tonight I worked to calibrate the magnetometer and the AHARS. It was rather windy when i got to the airport, and you need good GPS data to calibrate both, so i had to wait until the storms passed. First up was the AHARS calibration. This was pretty easy. Basically level the aircraft in flight attitude and let the G3x figure out pitch and roll offset. I also needed to do a vibration test on the AHARS once the engine was running. Next I did a magnetic interference test. Basically you start and turn off all the various electrical gizmos that could cause interference and manipulate the controls etc. You do this in 10 second increments. The magnetometer (which is in the left wing tip) passed the interference test.

I taxied to an open part of the airport and used my compass to ensure I was facing due north. I guess you can do the magnetometer calibration with the engine running and just taxi it. But I chose to shut down and just push the tail around. Basically all you have to do it rotate the plane 360 degrees and 30 degree segments. The display tells you what to do and when. Dirt simple. And I got a successful calibration.

Now with the aircraft warmed up, I taxied back to the hangar, tied her to my truck and did a full power run-up for the AHARS vibration test. This also passed. So now I have a fully tested and calibrated AHARS and magnetometer.  I also setup all the airspeed marking limitations tonight in the EFIS.


Misc wrap up work

Getting ready for the first engine start… but most of the things on my checklist for the engine start are complete. Many of the remaining items on my list need to wait until after the first start. So I worked on a number of small projects – some needed in the near future. Others not needed until whenever I decide I want them done.

Projects accomplished tonight. Some temporary seat covers made from pillow cases. Instrument panel white led lights hooked up. Foil added to the bottom cowl. Wheel pant fiberglass work. The instrument panel white LED lights are bright and will need adjustments. First, I need to bring them aft about one inch. This will provide much better visibility and reduce shadows on the panel. Second, I need to shorten the LED strip. Its a bit too long at the moment, which means my eyes can catch direct light at both ends of the strips. Shortening the lights will have the secondary effect of reducing the amount of light output. Currently its a bit too much even a low levels.  Lastly, I’ll need to improve the wire routing – its a bit ugly at the moment, but its functional and works as a proof of concept. Plenty of time between now and final paint!

Instrument Panel Finalization

There is a ton to report in this post. I won’t be able to cover it all. I’ve been working hard to finalize all the electrical wiring and avionics installations. I’ve finally gotten to the area behind the panel and the instrument panel itself. Things that were accomplished in this session: final install of pitot static boa lines, final wrapping and organizing of all wires and cables, removal of instrument panel, carbon fiber wrapping instrument panel, reinstalling all switches and avionics into the panel, labeling all switches, elt nut plate installation, and installation of a few wires remaining for functionality such as fuel pump switch to bus power and power for panel led lights.