Compass Calibration

[dsandson]

Right I've went through the pain of changing vibration dampers... and I'm not in a rush to do that again as it felt like I've just gently managed to force 4 square pegs into very small round holes!!

Any way I was wondering what people do for their compass calibrations? I'm used to doing a calibration every time I travel a reasonable distance (say Yuneec's 5 mile rule) but it really is very hard on the gimbal, and the dampers. Is there a way to reduce the wear? Or is 5 miles very conservative?

 

[NorWiscPilot]

Right I've went through the pain of changing vibration dampers... and I'm not in a rush to do that again as it felt like I've just gently managed to force 4 square pegs into very small round holes!!

Any way I was wondering what people do for their compass calibrations? I'm used to doing a calibration every time I travel a reasonable distance (say Yuneec's 5 mile rule) but it really is very hard on the gimbal, and the dampers. Is there a way to reduce the wear? Or is 5 miles very conservative?

hi dsandson,

I think the real question, related to a post-incident investigation, is: How do we want to answer any questions relating to "were the manufacturer's guidelines followed pertaining to calibrations and operations?"

Anyone and everyone is welcome to offer their opinions to your question. But... who holds the cards if something goes wrong, be it a warranty claim attempt, a crash forgiveness plan, insurance, et al? That, in my opinion, should be what governs anyone's standard operating procedures. Oh, and let's not forget the safety aspect of both the pilot, observers, and the innocents.

What's the old line... "do you feel lucky?"

Jeff

P.S. Not trying to preach... just a reminder to others who may stumble on this thread and perhaps have not read other similar posts as to pilot responsibilities.

 

[WTFDproject]

Remove the camera during compass calibration.

 

[NorWiscPilot]

Remove the camera during compass calibration.

Unfortunately, unlike the H480, the H520 must have a camera attached to initiate a compass calibration. To get into the calibrations at all, in fact (at least in my experiences so far.)

I believe I have read in the H Plus threads that a calibration can be initiated, the camera removed, and the calibration executed, but have not tried it as yet with the H520. [Ed. I believe I actually DID try the compass calibration/remove camera method on my H520. Did not work.]

Jeff

 

[10-8]

Remove the camera during compass calibration.

No need to remove the camera during calibration.

 

[arruntus]

Don't worry, by doing the calibration the dumpers won't suffer unnecessarily. If we get this way, at the end we fly without camera. I think that as long as you remove the camera when you're not going to use it, it's enough, at least for me it has been. When you have to use it you have to use it

The five-mile recommendation, I think I remember, is for North America only. In Europe they are 50km, which is much more distance, but even so when I think that I have passed 20 km I do it again, it costs 2 minutes and does not hurt. To annoy you, I do not think they have established that recommendation. There will be some reason, I was also surprised when I read it.

What really can do harm is to have a flyaway or an erroneous position that can mean having an accident.........

 

[Steve Carr]

The compass calibration is simply to compensate for the Earth's magnetic declination from true North. I can't imagine 5 miles being anything close to reasonable. I consider a compass cal requirement at hundreds of miles. You can refer to a map to determine the need based on where you travel. As you can see from the map, traveling N and S would generally not change the variation enough to worry about a calibration.

 

[10-8]

The compass calibration is simply to compensate for the Earth's magnetic declination from true North. I can't imagine 5 miles being anything close to reasonable. I consider a compass cal requirement at hundreds of miles. You can refer to a map to determine the need based on where you travel. As you can see from the map, traveling N and S would generally not change the variation enough to worry about a calibration.

View attachment 12539

That's my recommendation as well. In a year and a half, I have calibrated my compass less than 1/2 dozen times.

 

[DoomMeister]

I agree with Steve Carr on this subject for the most part. It depends where you live as to how far you can travel in any direction to have a significant effect on the compass calibration. My personal limit is about 5 degrees difference.

I snowbird between Michigan and Florida and find that I do not have to recal my compass from one point and the other. Refer to the map in Steve’s post above and you will see there is less than 5 degrees difference between central Florida and central Michigan.

Most travel east/west is a different story and recalibration would be advisable more frequently. I found this site to have good information globally and not just for the US and Canada Magnetic Declination (Variation) | NCEI.

 

[Graham]

Having been diving where there was a local magnetic anomaly (of which I was unaware) and become thorougly lost due to my compass being affected, perhaps having some local knowledge might be useful. Similarly, on one of my early H520 flights, I calibrated the compass and flew where there had been a 2nd world war ship breakers yard. The H520 flew the survey fine, but the results were not so good. I now wonder whether that was down to the compass calibration being affected by large residues of iron in the soil.
Local magnetic anomalies are a known issue in aviation; https://flightsafety.org/wp-content/uploads/2016/12/asw_may08_p18-22.pdf
I am unclear how these may affect the H520 flying at our altitudes, but assume that they will have some effect. Perhaps it's best to do the calibration at a known 'good' site. Then re-calibrate if you travel some distance and definitely recalibrate if something seems amiss when flying? UK and Ireland anomaly map; Record details |Magnetic anomaly map of Britain, Ireland and adjacent areas. Colour shaded relief. 1:1 50 000 series.| BGS maps portal | OpenGeoscience | Our data | British Geological Survey (BGS)

 

[arruntus]

Having been diving where there was a local magnetic anomaly (of which I was unaware) and become thorougly lost due to my compass being affected, perhaps having some local knowledge might be useful. Similarly, on one of my early H520 flights, I calibrated the compass and flew where there had been a 2nd world war ship wreckers yard. The H520 flew the survey fine, but the results were not so good. I now wonder whether that was down to the compass calibration being affected by large residues of iron in the soil.
Local magnetic anomalies are a known issue in aviation; https://flightsafety.org/wp-content/uploads/2016/12/asw_may08_p18-22.pdf
I am unclear how these may affect the H520 flying at our altitudes, but assume that they will have some effect. Perhaps it's best to do the calibration at a known 'good' site. Then re-calibrate if you travel some distance and definitely recalibrate if something seems amiss when flying? UK and Ireland anomaly map; Record details |Magnetic anomaly map of Britain, Ireland and adjacent areas. Colour shaded relief. 1:1 50 000 series.| BGS maps portal | OpenGeoscience | Our data | British Geological Survey (BGS)

The ship cemetery made us eat our heads, didn't it? xDDDDDDDDDDDddddddddddd

I think a lot of people always fly in the same area and they never need to calibrate because even if they move 50 km the variation is very small, even if it exists and they believe that it is not necessary. I think it's a mistake. Please don't let this become "it's not like that because I've never had a problem". Then another person goes and just pays attention, even though the official recommendations say otherwise, and bitterly regrets it.

In the first version of the manual already appeared the famous distance of 5 miles and we all throw our hands to the head. This is not possible. Then in a revision they put that for europe it was 50km. For Yuneec to keep saying that in North America it is 5 miles has to have a scientific reason, and not a belief. It's counterproductive for them, so there's no reason to keep insisting, unless it's really necessary......

 

[dsandson]

Wow, thanks folks! That was a lot of interesting information! My main concern was that i had to replace the dampers after only a handful of flights. 50km sounds much more reasonable. I work in and around Northern Ireland so its not such a big place.

 

[NorWiscPilot]

Wow, thanks folks! That was a lot of interesting information! My main concern was that i had to replace the dampers after only a handful of flights. 50km sounds much more reasonable. I work in and around Northern Ireland so its not such a big place.

It may be just me, but I’m thinking something else is going on to force a replacement of the dampers, if truly only a handful of flights were on them.

I’ve done a handful of compass calibrations alone, let alone many flights, though likely much less than the majority of h520 owners here. Still no issues with the dampers.

Now, full disclosure: my first E50 suffered from intermittent wavy or “jello effect” video brought on by camera/gimbal vibration. My dealer replaced the camera/gimbal. Second camera still had the vibration. Next attempt was to use the CGO3+ version dampers - non-jell filled. Worked for that camera.

Rest of story - the whole kit ended up being replaced for other reasons. Current E50 has the jell-filled dampers. Working just fine, I’ll including those handful of calibrations.

Jeff

 

[dsandson]

NorWiscPilot, thank you for that. I was able to detect the gimbal wobble from a brief video I took on my first flight. It then got worse and much more noticeable on the next series of flights. This E90 camera was a replacement from Yuneec UK. So perhaps they were defective from the start, or I just had bad luck.

Its good to see that others aren't having issues from the calibrations too.