Compass Calibration: Looking for Alternate Method

[N941WR]

I am (OK, used to be) an active backpacker, so I used my compass (see image, below).
I turned the prop vertical so I could line it up with vertical stabilizer (VS). I then turned the plane in each of the cardinal directions, using the compass to line it up, while sitting on the ramp, away from any metal buildings. If your airplane has tricycle gear, you might need a stepladder to sight along the VS and prop.

 

[jnmeade]

Reinforcing rod in concrete, buried power cables, underground pipes and similar factors can be a factor in selecting a spot for compass calibration.

 

[N941WR]

Reinforcing rod in concrete, buried power cables, underground pipes and similar factors can be a factor in selecting a spot for compass calibration.

Absolutely correct. If you use the compass method I described above, walk around with the compass and see if it is disturbed by any burred metal.

 

[Lon]

I am (OK, used to be) an active backpacker, so I used my compass (see image, below).
I turned the prop vertical so I could line it up with vertical stabilizer (VS). I then turned the plane in each of the cardinal directions, using the compass to line it up, while sitting on the ramp, away from any metal buildings. If your airplane has tricycle gear, you might need a stepladder to sight along the VS and prop.

This sounds like a great method for doing a calibration in a confined space too small for taxiing. But the Dynon instructions say calibration should be done with the plane in its flying configuration, i.e., engine running etc. Did you find that doing the configuration with the engine off worked well enough?

 

[N941WR]

This sounds like a great method for doing a calibration in a confined space too small for taxiing. But the Dynon instructions say calibration should be done with the plane in its flying configuration, i.e., engine running etc. Did you find that doing the configuration with the engine off worked well enough?

I did not have the engine running but had all the electronics turned on.

 

[sunfish]

I’ve done a rough ground calibration and taxi tests indicate I’m out by ten to twenty degrees according to the gps track, will an in flight calibration fix it?

 

[jakej]

Fly it & find out - do you really need an excuse to fly ?

 

[dbwindom]

I just performed another in-flight calibration, because my wind arrow seemed inaccurate. It's interesting to note, that the procedure in the manual casually mentions that varying the rate and pitch with INCREASE your calibration's accuracy. Until then, I was circling in a constant rate, maintaining altitude, and my "calibration index"? ( IDK if this is the actual term used in the manual) was stuck at about 120...totally acceptable, per Dynon, but still less than what I already had. I re-read the procedure...started flying climbing and descending circles, and the "index" started ticking higher!!

 

[sunfish]

126. Is that OK?

 

[dbwindom]

126. Is that OK?

If the number is green...it's within acceptable limits, per the manual.

 

[mrbizi]

Anyone know why the magnometer goes out of whack? It was working fine. Now it’s not. So I did a couple of inflight calibrations and got into green but it was still off by 20 degrees!!!! What the heck. My IFD was correct and in sych with my whiskey compass. What gives?

 

[Albee]

I don't know the answer to your question, but have you considered taxiing N, S, E, & W, using a GPS? On the ground, track = heading, and even a handheld GPS (or tablet/phone) would be a whole lot more accurate than a tablet/phone compass. Google Earth shows a pretty good sized ramp on the SE corner of the airport, and you might be able to establish reliable, accurate tracks on the cardinals while taxiing in that area.

This is what I did, and it worked okay: I did the airborne calibration and got okay metrics, but they got much better when I repeated the airborne calibration.