Author Topic: Temp Probe and Winds  (Read 230 times)

SteveB_Z5

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Temp Probe and Winds
« on: June 13, 2019, 07:33:03 PM »
Can anyone share their findings of changes in the displayed winds with the addition of a temp probe.  I don't have the probe for the CNV or CNII and I don't find the winds, that always seem to match within a degree or two and a knot or two, believable at times.  Over the field and I can see the sock is 180 degrees from what both CN displays are showing.  Yes, I had made a 30+ degree change before over flying the field.
I'm wondering if the temp probe would help with this.
Thanks for any info,
Steve

Evan Ludeman / T8

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Re: Temp Probe and Winds
« Reply #1 on: June 14, 2019, 05:18:05 AM »
The temp probe only slightly improves the TAS calculation under most conditions. 

I've been complaining about the vector wind calculation in non-circling flight for a couple of years.  CNv was "scary good" at about version 2.5, then took a big step backwards.  I'd rate the wind calculation performance as slightly worse than C-302 in current form. 

Check the airspeed page in flight and compare IAS to your ASI and TAS to GPS ground speed on a light wind day.  There should be very little error.  If there is, you may need to re-zero the sensors in CNv (reasonably easy to do).  This will improve gross errors in non-circling flight
Evan Ludeman / T8

Evan Ludeman / T8

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Re: Temp Probe and Winds
« Reply #2 on: June 14, 2019, 05:23:54 AM »
^^^ the point of that was to say "it's a known issue".  CNv development work was at a standstill for quite a while due to events well beyond CNi control.  We're hopeful that significant forward progress will happen again in the relatively near term. 
Evan Ludeman / T8

SteveB_Z5

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Re: Temp Probe and Winds
« Reply #3 on: June 16, 2019, 12:00:59 PM »
Evan,
I find the CN winds unbelievable quite often and wondered if the temp prob would help.  I did the sensor zeroing once before on my last glider.  I'll have to look closer at this gliders set-up.  Could you post or send me the how to zero instructions?
Thanks,
Steve

Evan Ludeman / T8

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Re: Temp Probe and Winds
« Reply #4 on: June 16, 2019, 06:05:36 PM »
procedure emailed.

Evan Ludeman / T8

MikeO

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Re: Temp Probe and Winds
« Reply #5 on: June 17, 2019, 07:20:52 AM »
Evan,
Any chance I could get a copy of the zeroing instructions for airspeed on my CNv. Mine is showing around 30kt on the ground - no wind - and the winds aloft vary quite a bit with direction change.

Mike Orindgreff
morindgreff at cox dot net

Evan Ludeman / T8

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Re: Temp Probe and Winds
« Reply #6 on: June 17, 2019, 11:53:51 AM »
Procedure sent. 
Evan Ludeman / T8