Author Topic: Indicated vs Ground Speed  (Read 250 times)

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xcnick

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Indicated vs Ground Speed
« on: August 04, 2022, 04:34:17 PM »
I have only just started looking at data in seeyou. It shows my Indicated Airspeed within a mile an hour of my ground speed. This doesn't happen to my friend with his ClearNav vario. (The same happens if I use the log from my clearnavII.)

Is there a setting I may have missed?

thanks
nick

Evan Ludeman / T8

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Re: Indicated vs Ground Speed
« Reply #1 on: August 05, 2022, 12:53:19 PM »
In general, igc files include position and altitude.  Speeds and winds as displayed in SeeYou or other flight analysis programs are calculated in the program.
Evan Ludeman / T8

xcnick

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Re: Indicated vs Ground Speed
« Reply #2 on: August 05, 2022, 05:24:06 PM »
Thanks,

I misspoke about the CNII, SeeYou displays IAS as I would expect from the CNII log. (first attachment 119):

The Clear Nav Vario log is the only log where IAS appears wrong. (attachment 120)

I now understand SeeYou is calculating. However both these logs from the same flight are calculated differently. The vario's IAS is wrong, which makes me wonder if the speed to fly software is making the same error as SeeYou.



Evan Ludeman / T8

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Re: Indicated vs Ground Speed
« Reply #3 on: August 06, 2022, 04:50:10 PM »
I don't see how it can possibly be a CNv issue.  It just records position & altitude (like CN2) in the log file. 
Evan Ludeman / T8

xcnick

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Re: Indicated vs Ground Speed
« Reply #4 on: August 06, 2022, 08:57:28 PM »
I don't know where the issue is, but doesn't record like the CN2 because the data is different for the same flight. I checked my neighbors CNV and it does the same thing. We have one more CNV on the airport, but it may be a few days before he is back.