My way point : Différence entre versions

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As a race mark, WP can be used with the following modes : '''Orthodromics pilot''', '''best VMG''' and '''VBMG''' ('''Constant heading''' and '''Constant Wind Angle''' don't use the WP.
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As a race mark, WP can be used with the following modes : '''Orthodromics pilot''', '''best VMG''' and '''VBMG''' ('''Constant heading''' and '''Constant Wind Angle''' don't use the WP).
  
 
Race mark coordinates can be found into Course instruction or on top right of the UI when mouse navigates over mark number (see screenshot).
 
Race mark coordinates can be found into Course instruction or on top right of the UI when mouse navigates over mark number (see screenshot).

Version du 22 janvier 2013 à 15:54

This option gives you the ability to have your own way point.

If no value has been filled, your Way point (WP) is the next mark, provided (lat,lon) are entered as '0'. When you fill a value (lat, lon) in the 2 WP text boxes, the next race mark is forgotten until you reach your waypoint.

  • A WP is considered as 'reached in VLM when the distance between 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..
    • By default qtVlm will set "heading-to-follow" with the last direction that the boat was sailing when the WP was reached and deactivated.


As a race mark, WP can be used with the following modes : Orthodromics pilot, best VMG and VBMG (Constant heading and Constant Wind Angle don't use the WP).

Race mark coordinates can be found into Course instruction or on top right of the UI when mouse navigates over mark number (see screenshot).

Wp depart exemple.png

Explanation

  • Departure is on 50°33'40"N 001°14'4"W
  • One race mark is on 51°23'03"N 009°36'00"W
  • Final mark is between 50°17'24"N 004°10'47"W and 50°15'00"N 004°04'48"W)

In our example, as the race has not started yet and the boats are still on the starting line, the WP is 51 ° 23'03 "N 009 ° 36'00" W 319.26 nm located at 282.1 great circle as indicated on the dial.

VLM MonWP defaut2.png

To program the next WP to be the same as the coordinates of the next mark, you must enter the value 0 into the boxes Lat and Long as in the picture below.

VLM MonWP defaut1.png

But with the next WP as the next mark, if you program the pilot for better VMG, you will become Grounded for sure, with a penalty guaranteed, as seen easily from the inboard course image below.

071228fastnet.png

Alternatively and more safely we should choose a suitable WP to circumvent the tip of Lizard (approximately 49 ° 57'N 005 ° 12'W). With a little caution, so as not to bump into the Point, the southernmost tip of Plymouth, retain 49 ° 48'N 005 ° 12'W. This entry is in decimal degrees, or 49.8 and -5.2. For the record, we must divide by 6 (= 1 ') the number of minutes, same for seconds.

VLM MonWP perso1.png

Save

VLM MonWP perso2.png

and the result is visible on the dial

VLM MonWP perso3.png

WP is 158.58 nm cap ortho 254.8

On the map you can see the WP and indicated route.

VLM MonWP perso4.png

So we can use the driver circle and better VMG to fail safe (if the winds do not change completely and send us all on the coast anyway (however is nature of the routing and mode of use of instruments).

The parameter @ WPH can choose the course exact to follow once the WP staff (My WP) is triggered. If enabled, the boat will take the course selected from the passage of the WP staff (see image below). This piloting alternative is very useful when passing between islands and tight areas.


WPH.png

Important: The system considers a WP be reached when the distance between the boat and the WP is less than 1/12 the speed of the boat at the last session, approximately the distance traveled during the last session (eg, a speed of 24 knots, the boat "reach" when the waypoint will be located within a circle with a radius ranging from WP 2000). Recent information is valid for racing with "vac" every 5 minutes (for races other "vaccine" should be adapted as appropriate) catégorisation