a problem with compass swing
Moderators: sky's the limit, sepia, Sulako, North Shore
Re: a problem with compass swing
I find it interesting that in an age of navigation technology that has made the lowly whisky compass almost a thing of the past (I think it is a thing of the past is some newer model aircraft with enough other redundancies built in), the FAA comes out with a new AC just last month, on how to swing a compass.
I see they say that one can use the GPS in flight, as long as the variation can be determined within 0.2 degrees. I still don’t know how one can know, in flight, if their heading and track are the same within 0.2 degrees at any given time.
https://www.faa.gov/documentLibrary/med ... 43-215.pdf
I see they say that one can use the GPS in flight, as long as the variation can be determined within 0.2 degrees. I still don’t know how one can know, in flight, if their heading and track are the same within 0.2 degrees at any given time.
https://www.faa.gov/documentLibrary/med ... 43-215.pdf
Re: a problem with compass swing
I've noticed that some hand-held devices (specifically a Garmin Aera 500 series GPS) contains a speaker (hence a magnet) and this affected my compass reading significantly. Moving the GPS helped, but in the end, I ended up pitching it and stuck with a Garmin 396 instead.
Re: a problem with compass swing
The irony, you're forced to forego more modern technology (the Aera) to make antiquated technology work (the compass). The better solution is to remote mount a magnetometer, put a Dynon or Garmin glass panel on the dash, and toss the whiskey compass into the scrap bin of history.flyguy73 wrote:I've noticed that some hand-held devices (specifically a Garmin Aera 500 series GPS) contains a speaker (hence a magnet) and this affected my compass reading significantly. Moving the GPS helped, but in the end, I ended up pitching it and stuck with a Garmin 396 instead.
When flying most of us have a backup magnetic compass and GPS in our cell phone anyway. And sometimes a backup backup in our tablets. Regulations haven't caught up with technology, that's all.
Re: a problem with compass swing
We have a compass cross check system that replaces the requirement for annual compass swings, just like the big jets.
Every certificated aircraft must have an independent standby indicator in case of electrical failure. It doesn't matter how many iPads you have, or gps's.
The whiskey compass is not going anywhere.
Every certificated aircraft must have an independent standby indicator in case of electrical failure. It doesn't matter how many iPads you have, or gps's.
The whiskey compass is not going anywhere.
Re: a problem with compass swing
GyvAir wrote:No wet compass there:
The small screen on the LH side with the attitude and mini HSI is likely the standby one, may not be the conventional wet compass, but there will always be a standby
Re: a problem with compass swing
I presume it is, as well.ben_davis wrote:The small screen on the LH side with the attitude and mini HSI is likely the standby one, may not be the conventional wet compass, but there will always be a standby
Point being, though: I've seen hundreds of aircraft with standby HSIs incorporating an independent standby compass, but this is the first aircraft model I'm specifically aware of, where the old whiskey compass or equivalent has been omitted.
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Re: a problem with compass swing
Just went through this exact problem. Take this for what it's worth, and people make mistakes. Had a compass swing, got it back from shop, and everything seemed okay, for a bit, then, everything went off about 20 degrees. We thought it was the magnets in the electronics (which it still may have been), but it took 2 AMEs and 2 pilots to figure out that the the error was pretty close to the variation in the area. Our next step was to ensure we had an accurate compass rose, everything turned on, and then did the swing. For the love of god, the compass was initially swung to true north, not magnetic north. All good now.