Expedition Navigation Software 
1 - unplugged
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Logging - Missing True Wind Info
The log files I am working with contain Awa, Aws, Bsp, Hdg but columns for Tws, Twa and Twd are empty.
I am trying to play with the program Model Accuracy (compares recorded wind data against model gribs). I think it needs Tws, etc... Since those are calculated values. How do I get them to log?
Last edited by unplugged (10/31/2018 7:57 am)
- Nick
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Re: Logging - Missing True Wind Info
When they are updated or received in Exp, they are written to the log file.
If there are none, it suggests you instrument system isn't sending them. If that is the case, you can tell Exp to calculate them.
- DuncanR
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Re: Logging - Missing True Wind Info
To state the obvious, you can't play with MA without TWS and TWD.
What instrument system are you using? Check your instruments - are those values showing on your instrument dials - in which case check the Expedition data stream to see if they are being passed or are the dials blank, in which case your system is not doing the calculation at all?
Depending on your instrument system, it may be a question of just changing some variables.
Nick, is there any way to post-calculate TWS/TWD after the event?
- unplugged
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Re: Logging - Missing True Wind Info
Figuring out that missing TWS and TWD were why MA wouldn't work took a day or 2.
For the logs I had, I was able to back fill using the data that was logged and formulas I found online. That got MA working. Still need to play more.
I asked the skipper to check the boxes under Exp Calc to have it calc and log Tws and Twd so I can have them in the future. Boat has RayMarine throughout. Not sure why or if it should be putting TWs and Twd on the bus.
Thanks
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Thread Starter- Nick
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Re: Logging - Missing True Wind Info
Probably the Raymarine isn't sending TWA, TWS or TWD over the network. I think I have heard of that before.
- axyl
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- Registered: 8/20/2018
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Re: Logging - Missing True Wind Info
We have Raymarine gear too; which doesn't send TWS/TWA so we use Expedition to calculate.
However, I can't work out why we get spikes in our TWS readings? Any ideas Nick?
In this image, the wind speed on the day rarely ever went above ten knots, but we have a bunch of higher values, up to 150kts for TWS???????
I'm going to check again, but this should be set with Expedition calculating the values for TWS, TWA and TWD.
Last edited by axyl (11/09/2018 12:17 am)
- Nick
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Re: Logging - Missing True Wind Info
Heel and leeway?
- DuncanR
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- From: Up and down East Coast Aus
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Re: Logging - Missing True Wind Info
I'd be checking your GPS for spiking. If it was - and it would have to be really obvious to have this effect, it may well be pushing your leeway number all over the place.
Load the logfile, if it is the problem, it will be really obvious.
- axyl
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Re: Logging - Missing True Wind Info
Thanks for the input. I'm not seeing anything obvious at all.
Here's an hour showing Heel and Leeway and the TWS spiking often into the 70's and above.
I'm far from an expert here, so any other suggestions would be appreciated.
Down wind is no different.
- benhowett
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Re: Logging - Missing True Wind Info
Hi Axyl - Can you upload a full log file which demonstrates the issue?
Last edited by benhowett (11/16/2018 3:07 am)