Electronic devices in cockpit.. yah right..Leson learned

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Addicted2climbing

Pre-takeoff checklist
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Addicted2climbing
Hello all,

So I am at the point in my training where I am doing longer flights preparing for the XC phase. Yesterday, we flew from KVNY to KLGB and I was following the VOR that takes you right over LAX. While on the way there, my instructor noticed that our compass seemed to be off a bit but my VOR indicator was showing the correct track. We flew to longbeach did a few landings in medium rain (something new) then headed back home. On the way back the Compass and the VOR once again did not jive. We could not figure it out, then I had a thought. Just maybe it is my Iphone under the dash cover running cloud ahoy that is causing the shift in the compass. I pull it out and the compass swings back to the correct heading. It was about 20 degrees off... He laughs and says I had no idea you put that there. Like an idiot I had put it directly in front of the compass under the cover. Needless to say from now on I need to find a new home for the Iphone when running cloud ahoy... I need to make a yoke mount I suppose...

Whats crazy is I had been flying some of my solo pattern practice with it in the same location and did not notice. But at least I never left the pattern so not such a big deal.

Anyhow lesson learned...

Marc
 
No I had it just running normal with Cloud Ahoy to keep track of my flight. Can it run in airplane mode with the GPS running?

Marc
 
Addicted2climbing said:
No I had it just running normal with Cloud Ahoy to keep track of my flight. Can it run in airplane mode with the GPS running?

Marc
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No. I tried a long time ago to get a GPS location in airplane mode and it didn't work. That was a long time ago when I was only barely familiar with it. There might be a way to make the GPS work in airplane mode.
 
I doubt turning on airplane mode would have helped. Any magnetic device near a compass will through it off.

Airplane mode cuts the GPS off too, in the Iphone.
 
I fgured as having gps in airplane mode woudl defeat the process I think.

My thoughts as well, pretty much anything that close th ethe compass would affect it. I am just glad the issue was discovered now before I went on a solo XC. However when solo in the cockpit I woudl also put the iphone under the seatbelt in the passenger side.

Marc
 
Addicted2climbing said:
My thoughts as well, pretty much anything that close th ethe compass would affect it.
Click to expand...

I think there's your answer. Doesn't matter if it's an iPhone running CloudAhoy or a big keychain with a dozen metal keys...putting something like that close to the compass may make it unreliable. Electronic or not is likely irrelevant with regard to a whiskey compass.
 
Mike I said:
I think there's your answer. Doesn't matter if it's an iPhone running CloudAhoy or a big keychain with a dozen metal keys...putting something like that close to the compass may make it unreliable. Electronic or not is likely irrelevant with regard to a whiskey compass.
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Yea, I noticed that while putting my David Clark headset up on the glare shield. It turned the compass.
 
ChrisK said:
... wow. That's kind of a dumb design.
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Not really. Airplane mode disables the radio interface(s) on the iPhone/iPad. I believe that there are still some airlines, for example, that prohibit passengers' in-flight use of GPS.

As others have stated, any device which disrupts the magnetic field of the compass can cause deviation errors.


JKG
 
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The airplane I fly, if you turn the windshield heat on, it gives over 30 degrees of compass error lol. Anything that gets near the compass will cause some sort of error it seems like.
 
I have something to say about this.

Aeric on POA put his iPhone and Cloud Ahoy in the back of the 150 but due to heat the iPhone turned off and Cloud Ahoy stopped. So even if you put it far away from the compass there can be issues.
 
kimberlyanne546 said:
I have something to say about this.

Aeric on POA put his iPhone and Cloud Ahoy in the back of the 150 but due to heat the iPhone turned off and Cloud Ahoy stopped. So even if you put it far away from the compass there can be issues.
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But that's an electronics issue, not a compass issue.
 
They say to put CloudAhoy so it can see the sky. Last week I did a night flight and put my iPhone in my pocket thinking it can't see the sky at night. Guess what. It still worked and it was still able to track me. For my last 2 solo x-countries I put my phone in my pocket. I use to mount my phone on a GoPro suction mount with velcro but don't do that anymore since it works fine in my pocket.
 
Whn I put it in my pocket or on the passenger seat I had a low accuracy. When its on the dash under the cover (to avoid heat and sun) it has great accuracy, but then I get the compass error. I may just try and put it on the yoke. I have put it in my knee board with good results, but it rattles around and gets in the way when i open the kneeboard. I may try some velcro.

Marc
 
I notice the same thing. It loses signal when it's sitting in my Hello Kitty bag. Put it on my lap and it's all good.
 
Just an FYI - if you turn off cellular data and wifi, you will essentially get "Airplane Mode" except the GPS will still work.

ForeFlight has a FAQ about it here: http://www.foreflight.com/support/gps

Go to Settings\Wi-Fi, select "Off".
Go to Settings\General\Network\Cellular Data, select "Off".

Then go to Settings\Location Services, select "On" for Location Services and also ForeFlight.
 
'always put my Spot Tracker right on top of the compass.... never as much as 1 degree difference.... go figger.
 
CT4ME said:
'always put my Spot Tracker right on top of the compass.... never as much as 1 degree difference.... go figger.
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Well, it doesn't have a giant rare earth magnet in it, so it's effects are limited to the fields produced in circuit... from what's probably only a 3.3V lithium ion cell, and it's probably pulsing the micro controller/CPU on and off with a hardware interrupt based off of the CPU clock source (if it's even external anymore... most are on-die these days unless more accuracy is needed).

So it ain't much of a magnetic field generator...

But still... Kinda a bad place for the thing... ;)
 
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