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New forecast is used by VLM a few minutes after each download ... and there could be small or even big jump in wind info at that time, depending of the quality of previous forecast.
 
New forecast is used by VLM a few minutes after each download ... and there could be small or even big jump in wind info at that time, depending of the quality of previous forecast.
  
GRIB files used by VLM are available here: http://grib.virtual-loup-de-mer.org/ and come from the NOAA.
+
GRIB files used by VLM are available here: http://grib.v-l-mr.org/ and come from the NOAA.
  
 
= I'm looking forward to the release of the source =
 
= I'm looking forward to the release of the source =
  
the sources are here : http://source.virtual-loup-de-mer.org
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the sources are here : https://github.com/v-l-m/vlm
  
 
= Is there any way to see the tracks of the real boats on the map? =
 
= Is there any way to see the tracks of the real boats on the map? =
Ligne 63 : Ligne 63 :
 
Your boat '''has to''' be seen north (or south, depending of  the hemisphere) of the ice gate.
 
Your boat '''has to''' be seen north (or south, depending of  the hemisphere) of the ice gate.
 
This doesn't mean you have to cross the gate (but of course you are allowed to).
 
This doesn't mean you have to cross the gate (but of course you are allowed to).
 
= How can I easily loose 73 places or more at the end of the  VLM Vendee Globe Race? =
 
 
'''What happened.'''
 
I ran aground. I sent a good route to finish the race to the autopilot using VBVMG. I did not check that the last waypoint went between the gates and woke up the next morning with the boat hard against the French shore. I had to create a new route to finish and lost 75 places.
 
 
'''Why did this happen?'''
 
The boat probably made it to the waypoint, but did not cross the finish, so what happened afterwards?  Once the boat reached the waypoint, it appears it continued sailing, but in what direction?  Was it still using VBMG?  Why wouldn't it have gone towards the finish line (next waypoint) or perhaps just stopped at the end of the route and sent an alarm? Does the program have some of these choices?
 
'''
 
Answer from Maitai:'''
 
 
The VLM My Waypoint documentation states:
 
"If no value has been filled, your Way Point (WP) is the next mark, provided lat,long are entered as '0'. When you complete (lat, lon) values in the 2 text boxes, the next race mark is forgotten until you reach your waypoint. "
 
 
* First of all, a WP is considered as 'reached'' in VLM when the distance beween the boat and the WP is less or equal to the distance the boat sailed during the previous crank (vacation). So in fact the WP is always reached *before* the boat hits it.
 
 
* After a WP is reached, what happens depends on how the WP has been set-up:
 
 
** If there is a "Heading-to-follow-after-WP", then the boat will be set in heading mode with this value. Nice, but if the wind happens to come from that direction, you might not move a lot...
 
 
** If there is no such value defined in the WP (i.e. it has been set to "-1"), then the boat will keep the same navigation mode (VBVMG, VMG or ORTHO) as the one it had before reaching the WP, using that mode toward the closest point of the next race gate. Nice again, but if there is land between the boat and the next gate that might create problems
 
 
'''Follow up:'''
 
 
There is no way to find out, but I unknowingly probably had pilot instructions set on a "Heading-to-follow-after-WP"  because the boat went ashore, rather than  ''-1 '' to continue to the closest side of the next race gate (the finish)!
 
 
There is an option in qtVlm for that and probably this is what happened to you. By default qtVlm will set "heading-to-follow" with the last direction that the boat was sailing when the WP was reached and deactivated.
 

Version actuelle datée du 8 février 2018 à 11:42

The french FAQ is much more complete, please help us to translate...

Does the game take current and tides into effect

No tide, no current, no sail adjustment... only the wind and it's usually enough to be interesting. But there are ideas floating around about currents...

Why did it take me so long to find this site?????

  • Q: Virtual sailing is pretty sweet... my campaign is a hell of alot cheaper on the computer then in real life... why did it take me so long to find this site ?
  • A: Maybe because it's basically a french site, even if there are players from many countries. Please add english content here, so it's going to be better known by search engines.

What the ortho stands for ?

Ortho stand for orthodromic route or "shortest route".

What the loxo stands for ?

Loxo means Rhumb line route or constant angle route.

Is there a way to withdraw the boat from a race ?

yes, the link is now on the home page (Home link) or on your profile page (Profile link or click on your name in upper left corner)

Is the weather the current weather until the next update or is it the forecasted weather in 3 hour blocks ?

Weather GRIB files are downloaded from NOAA every 6 hours, at 3h35, 9h35, 15h35 and 21h35 UTC, these forecast are not continuous but in steps of 3h between the various forecast (0h (observations), 3h, 6h, 9h... 24h). VLM makes an interpolation between two time stamps.

New forecast is used by VLM a few minutes after each download ... and there could be small or even big jump in wind info at that time, depending of the quality of previous forecast.

GRIB files used by VLM are available here: http://grib.v-l-mr.org/ and come from the NOAA.

I'm looking forward to the release of the source

the sources are here : https://github.com/v-l-m/vlm

Is there any way to see the tracks of the real boats on the map?

No, there no way to get track of real boats. We only have their position (eventually you could use saved pics with their positions to create you own tracks).

What happens when we cross the date line (meridian 180) ?

Grib files are in GMT, so no problem with that. Beware of the bvmg, as it has an issue with the date line (well the meridian 180).

What is the difference between Best VMG and optimum road (as seen in VMG for VLM) ?

  • Optimum road take in account the fact that sooner or later you will have to "Tack" or "Gybe" to reach your WP.
  • Optimum road could be = to direct road.

Note that the VBVMG buton compute the optimum road (as seen in VMG for VLM).

I am having trouble figuring out how to enter waypoints. Just typing the values into the boxes doesn't seem to work

Coordinates of waypoint should be in a decimal format ... e.g. 5°30'S 45°15'E = -5.5 45.25 (here a tool for conversion: http://www.fcc.gov/mb/audio/bickel/DDDMMSS-decimal.html )

Attention! S & W have a negative value and N & E a positive one.

What is an Ice Gate ? What to do with it ?

Ice gates aim (in real life sailing) at preventing skippers to sail too near of Artic or Antartic. Your boat has to be seen north (or south, depending of the hemisphere) of the ice gate. This doesn't mean you have to cross the gate (but of course you are allowed to).