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HomeHomeDiscussionsDiscussionsiFly General Di...iFly General Di...ATC and iFly disparity in location?ATC and iFly disparity in location?
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6/7/2014 3:23 PM
 

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6/7/2014 3:50 PM
 

I agree with ComputerDoc; Shane's theory would result in offset errors, not "wrong diameter" errors. I will try to compare my Nexus 7 airspace/position depiction with a G430 or G530 depiction sometime in the next few days and will report back if I get it done. Comparison with a TSO'd navigator should tell the tale.

FWIW the airport distance shown on the panel boxes and on the N7 has always matched when I have compared them. It never occurred to me that they wouldn't.

 
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6/7/2014 5:00 PM
 
Shane wrote IN PART:

I'm curious if everyone seeing this is on a Sectional chart. I'd be surprised if you saw this same discrepancy on Vector Mode. ............

I'd be interested for someone to make that same flight or test and flip from Sectional to Vector to see if there is a discrepancy between modes. Vector Mode is rendering airports, towers, airspaces precisely based on the FAA's database.

If someone will report back their findings, I've personally seen this on many sectional charts... My waypoint or position over the sectional being slight off, up to a mile in cases. That's why I use Vector Mode more around critical airspaces. I hope this helps.




Hi Shane,

Well I tried your experiment today (switching between Sectional mode and Vector mode while approaching the class-D airspace perimeter.)
In fact I also had iFly iPad open and had it in Vector mode while in Sectional mode on the720.

Both the perimeter shown in vector mode and the perimeter shown in sectional mode are (according to ATC and the distance to airport readout on iFly) at about 1.0 to 0.7 miles INSIDE the 5 nautical mile radius.
In short, whether I have Sectional or Vector view on if I trust the lines shown on the moving map I could be about a mile into their airspace and not know it.
At least I can make that statment for the current Klamath sectional area map and the airport MFR.

Alex
 
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6/8/2014 2:43 PM
 
Jim said, "I guess the answer is to always assume your deplicted location could be off as much as a mile or so. Fly accordingly. That should work for VFR, not so much for IFR."

Why would you be reliant on a non-certified tool like iFly for IFR anyway?
 
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6/8/2014 3:03 PM
 

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HomeHomeDiscussionsDiscussionsiFly General Di...iFly General Di...ATC and iFly disparity in location?ATC and iFly disparity in location?