Air glide Vario family versus S100 LXNAV - Comments on Winds and Performance?
On Saturday, December 15, 2018 at 6:22:33 PM UTC-8, wrote:
I used a small hiking compass to look for magnetic fields before mounting the sensor case. I mounted it in the forward nose area.
To set up the Butterfly unit you fly figure 8's. This gives a score. I was able to get 8 out of 10.
I needed a longer cable from the sensor unit to the display. I was able to find one online and didn't need to get it from Air Avonics.
There are many parameters that can be changed. It seemed to look like a development project adjusting lag time, T.E. compensation etc. I've tried different ways to get static pressure on the plane also. My hope was for a vario that shows lift and not energy change. Meaning not showing stick thermals. I've not been able to achieve that. Not sure such an instrument exist yet.
You can also use the ISU itself, with a longer cable. Move it about and see if the heading indication on the display changes. To be thorough, you need to do it on several different headings. For example, with a 3' cable move it 3 feet away from everything, note the heading. Move it into the proposed location and see if the heading is any different. Switch different stuff on and off and again see if the heading changes.
Compasses and speakers are the most obvious moving magnetic fields, but power cables to instruments - especially if poorly wired - can also be a source. Instruments should be wired with paired power and ground twisted together, and terminated to busses close together. That will minimize the stray magnetic fields. Run them as far away from the ISU as possible.
That all said, I haven't found it to be horribly sensitive. Common sense - and perhaps some luck - will make it work well. In the above test, it didn't affect my compass, nor my compass it, until they were less than 6" apart. A speaker can be much worse, but the tiny speaker in my spare Ilec vario didn't affect it at all.
In my glider, the long term average wind tracks the CN vario pretty well, but the instantaneous wind is much more dynamic, and I'v been convinced it is accurate. I can find shear lines, wavelets, rough thermal centers that were otherwise invisible.
|