Back to Melges 24 Croatian Nationals Page
Some of the “SailViewer App” insights of Race 7
Click on the link below to download the logs of the race to be used in SailViewer App. To unlock the trial period, please contact the developer at: [email protected]
Race Course
The race course was significantly skewed. The upwind mark was approximately 353 degrees, while the average wind direction was 11 degrees. This has caused boats to sail more than double the time on starboard tack upwind than on a port tack. It was even more visible on the downwind where boats sailed almost all the leg on port tack.
Start
As the Pin side boat has no log, the pin end is set exactly at the position where an OCS boat (Tutta Forza) TTFZ crosses the line at zero seconds. So in reality it could be that pin was even a bit lower. The line was biased by 28 meters of upwind distance, favoring the RC side.
An interesting number is that Strilica (STRL) is shown even a bit in front of an OCS TTFZ. So they must have been very close to the line, too. (Luckily no VAR in sailing yet). The best start was done by Iggy, just 1 meter behind the line, only 5% of the line length from the favored RC boat. Three boats that clearly started late were Zen (not far from the line, but reaching for too long), Razjaren (doing the tack behind the line and crossing it 19 seconds behind), and Joyrunner (18m behind the line and on the unfavored side of it, but with the best VMG at zero seconds). The upwind distance between the leading boat and the last one at the gun was 40m.
After the start, Fjonda (FJND) took the lead with clearly better acceleration than Iggy. Strilica also showed good speed and Mataran (MTRN) managed to keep the height, win some height to Strilica and survive the difficult start position. Other than this, the strugglers that were forced to tack (RZRN, OBWN, and ZEN) collected good lift and then a header to tack on it. They managed to get back in the fleet, their high VMG shown as the green and the black line on the top of the others in the VMG graph.
1st Upwind
With the course so much skewed, boats should focus on sailing on Starboard and saving the short port tack for when it is really good to be on it. Using the port tack too soon creates a significant risk of not being able to use further shifts or getting kicked over the layline. However, as in the race before this one, there were strong right gusts and shifts on the right side, creating an opportunity to end up solid even if going right. It can clearly be seen with Razjaren (RZRN) gaining a lot after having not the best start and leading around the top mark. The group that rounded just behind them (MTRN, STRL) was using the left side and saving the tack for the very last left shift and gust. They were patient and not tacking earlier since they were lifted all the way to the left corner and only there got the left shift.
Apart from this, the VMG graph shows big gains from Razjaren while sailing to the right side. Also, the big VMG drops from Iggy (bad tack, 18m loss), Zen, and Fjonda (deep bear away behind another boat)
1st Downwind
Leading at the top mark, Razjaren and Strilica decided to go for a gybe around the offset. That move makes all the sense with such a skewed course and boats sailing almost the straight line on port tack to the gate. But the race before, this move didn’t pay because the boats doing a straight set were having more pressure sailing towards the mark. Also, there was significant wind shadow from the boats sailing to the offset mark. This downwind was similar to the last race and Mataran, Obi-Wan and Fjonda gained quite a lot to the leaders. Also, the app shows the wind direction of 5 degrees at the beginning of the downwind leg and 15 degrees at the end. That means that Strilica needed to sail in an unfavored shift after gybing to starboard (see pic below).
2nd Upwind
The second upwind was similar to the first one, boats going left all the way sailed more and more lifted and caught the left shift and gust at the left corner. Boats tacking to the right played the shifts. Gains and losses were made by using the shifts in the right way, with Mataran having the best upwind by going full left. Gate bias was approx 8m, giving an advantage to the right-hand one (looking upwind). Iggy has sailed 20m below the gate marks, therefore losing more than 40m of straight line distance.
In the picture above it is clearly visible how every boat rounding the right-hand gate has gained at least one place (lines crossing on the “Distance to Leader” graph). Even though the bias was only approx 7 meters, much less than it sometimes can be. Razjaren and Panjic gained one place and Strilica two. Their gain to the leader was on average about 13m of upwind distance after the mark rounding.
2nd downwind
2nd downwind was different in a way that boats that have gybed at the top sailed lower than the boats that did the straight-set. The gain was not very big. Boats from behind were closing on the leaders with more pressure.
Some other values
The picture above shows the heel numbers in upwind sailing with maneuvers removed. The boat that is quite away from all the others is Razjaren, with the heel a bit under 10 degrees. On the other side, Fjonda sailed at more than 16 degrees, maybe due to a lighter crew. Other good-performing teams were around 12 degrees of heel. Heel travel from Joyrunner was calculated on another device (SailMon) and Strilica had a higher refresh rate of the logger, so shows more travel than it actually is. Another significant difference is the Angle to the wind of Mataran which is sailing quite higher (35.6 degrees) and the speed of Razjaren, 6.13kts. Two of them have almost the same upwind VMG.
On the downwind legs, Mataran was having the most leeward heel (4.57deg) and Iggy was the flattest (1.52deg). Strilica has spent almost one and a half minutes more time downwind than Mataran.
The whole race ranking graph shows Mataran (yellow) working its way to the top while Strilica (purple) was losing places all the time. In the end, it decided the final result of the regatta.
Tracker Videos From The App
All of the above was analyzed and created using the SailViewer app. This page shows just some of the many features that the app has.