P2V flyers, do you hook it? (i.e. Does you P2V drift?)

[ianwood]

Reaching out to our P2V cousins... read this: viewtopic.php?f=19&t=9264

All of us P2 (non-vision) guys are so new, we don't really know what's what yet but maybe someone here knows. So, do you hook it? And if you do, which way and where are you? And if you are tempted to reply with "magnetic declination", answer me this:

• Shouldn't the compass heading be adjusted for declination automatically once the home location is recorded? It's a simple lookup table based on LAT/LON.
• When I switch to ATTI, fly for a bit and then back to GPS, it stops! No more hook. So, did the Naza finally adjust the compass heading for declination like it was supposed to do?

http://www.ngdc.noaa.gov/geomag/WMM/dat ... D_MERC.pdf

I am in LA where the declination is 12 degrees. Anyone left of Colorado should be influenced by it enough to notice as should those in the Northeast. Those of you in UK/Europe won't notice it much.

 

[ianwood]

Re: P2V flyers, do you hook it?

Okay... Let's try this one again... Do any of your P2Vs drift left or right after going straight forward or backward? If so, how pronounced is it and where in the world are you?

 

[Pull_Up]

Re: P2V flyers, do you hook it?

Perhaps as you predicted, don't notice mine doing that at all here...

 

[mr_3_0_5]

Re: P2V flyers, do you hook it?

Haven't noticed mine doing it either I'm in Florida

 

[ianwood]

Re: P2V flyers, do you hook it?

Western Europe and Florida are both within +/- 5 degrees of true North which is within the built-in adaption range of the Naza M v2. Therefore, any minor hook in initial flight will quickly disappear on its own. You have to be in an area where the declination is > +/- 10 degrees to have an ongoing issue. So far, I've got about 7 people in such areas with the same symptoms. Affected areas include:

• Western US and Canada
• Northeastern US and Canada
• South Africa
• Eastern OZ and all of NZ
• Northeastern South America

I will be shimming my compass today or tomorrow with the appropriate offset and testing to see if that eliminates the hook and course lock issues. How or why the Naza does not compensate for this automatically with a look up table is beyond me. Equally dumbfounding is the lack of a basic physical adjustment as with the Naza integrated GPS/compass puck.

 

[nhoover]

I don't really notice the angle problem while flying straight, but as soon as I let off the stick, it drifts left - about 20'. It will then slowly drift back right about 10'. If I reverse, it does it as your diagram shows. It hovers awesomely in one place, no circling ever.

I have calibrated a million times, all directions. I brought a laptop out to the field where I am FAR from anything metal and did advanced IMU calibration. Nothing seems to help.

Initially, my P2V did not have this problem. I noticed it only after installing the Flytrex core around flight #20. I've since calibrated without the Flytrex but no difference. I've just lived with it for the last 35 flights and it's ok - but I remember how nice it was when it didn't do that.

It seems like it gets a little better during each flight but that might be my imagination. But now that you mention ATTI mode...maybe that is the answer?! I don't use it every flight, but often. Will test carefully tonight.

I am curious to hear how the shimming goes. I'm in Northern California (37.3, -122).

 

[kmgibbs]

I live about 25 miles north of Seattle and have noticed the same problem. Currently, (from a pilot friend), we are about -20 correction. Have not tried the GPS-ATTI-GPS technique yet.