How accurate are the Skyview ADAHRS?

[nigelspeedy]

Today I borrowed the $30,000 air data test box from work and did a calibration of both my Skyview ADAHRS. Turns out they are quite accurate. Both gave very similar results. Airspeed threshold was 20 kias, below which they did not indicate (not a suprising result), from 20 - 50 kias about a 1 knot error, then essentially no discernable error from 50 to 300 kias. That should do the job for most of us. Altitude error varied approximately linearly by 60' over the test range of -1000' to +30,000'. Just for grins I took one of them to 40,000' where the error increased to 300', but this would not really be a factor for most. By using the hardware calibration and a -30' offset I was able to get less than 10' error from -1000' to 15,000', again more than accurate enough for my RV-8. These results still leave plenty of margin for some position error and the possibility of meeting FAR 23 requirements, if you were worried about such things. Not sure what the design spec for these items was but if this test of two ADAHRS is representative of the fleet then I would say they will do a great job for the vast majority of EAB aircraft.
Cant wait for v3.2 and VPX interface.
Cheers

 

[dpbarnes]

Great information. Thanks for sharing.

 

[vasper]

I just had my system checked by the local avionics shop and the technician seemed impressed by the accuracy of everything. I think he said that the altitude was only off by, at most, 10' up to 20,000' so you just can't ask for anything more than that.

 

[rogersmart]

I have an IFR check just before Oshkosh and same result, My Skyview, D6 and steam Alt were within 20' all the way up. I would like to poll you on your experiance with your local shop. Mine had to be convinced they could even do the check legally and then wanted to charge $250 per altimeter even though they ran them up together at the same time in the plane, they ended up charging $500 (2 alt) for the IFR cert.