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Clipper Round TheWorld (external link)
Virtual Regatta (external link)
This page refers to the Virtual round the world sailing race game and the BRITPACK 7 team. This Sydney to Hobart stage distance is 710 nautical miles was expected to last about 3 days. It actually lasted 3 days and few hours. The start was at 2am GMT on Saturday 26th December 2015.
To join in the race game go to Virtual Regatta (external link) and invent your boat. Its free of charge for a boat with basic sails and manual steering. You can pay for options: faster pro sails, a route waypoints programming capability and automatic locking of the wind angle. Boats with options are called AO (avec options). Boats without options are called SO (sans options). In the team competition the scores for SO and AO boats are adjusted to compensate for the difference. Obviously, in the main individual boats race, an AO boat does better and has more chance of winning a prize. The number of competitors is now over 36,000.
Our Britpack 7 team comprises 8 boats, the first 5 of which will score in each race. We have a 9th boat, Kames Bay, standing by, in case someone wants a rest.
In preparation for the start of this leg 5, watch this video :
Preparation for the Sydney Hobart race.
Actual real race start and finish charts from December 2014:
I'm wondering if the route I have marked in orange is a permitted route !
Some instructions on how to sail:
If the objective is upwind, that is you need to go against the wind direction, then steer in a zig-zag fashion, approx 42 deg either side of the wind. The wind angle displayed will be 42 deg or -42 deg. When you tack, though an angle of 84 deg, you boat will briefly slow down (10% slower during next 10 minutes), so minimise the number of tacks or zig-zags.
If the objective is downwind, that is you need go down in the direction which the wind is blowing towards, then steer in a zig-zag fashion, approx 38 deg either side of directly downwind. The wind angle displayed will be 142 deg or -142 deg. When you gybe, through an angle of 76 deg, your boat will briefly slow down so minimise the number of gybes or zig-zags.
If you look at the "POLAR" corresponding to the wind speed you can determine what wind angle to apply. In the case of upwind or downwind sailing use 42 deg or 142 deg as illustrated for 9.8 knot wind speed.
For other directions, where the wind is more or less sideways consider steering approximately directly towards the objective. If the objective is a very long way away it may be better to choose a wind angle where your velocity made good (VMG), towards the objective, is the highest. You will not be going directly towards the objective but you will be getting closer to it most rapidly. An example is shown in orange. The objective is very far away to the left, at 90 deg to the wind. The optimum steering wind angle for best VMG is 110 deg, you are 20 deg 'off course' but your boat speed is 9.5 kts and VMG speed is 8.7 kts, compared with 8.3kts if you steered at exactly 90 wind angle.
I've made a calculator that is supposed to help: Clipper 70 VMG calculator but I make no claim or guarantee that it gives correct results!
Note the important broad reach where the boat speed is maximum, around 120 deg wind angle. This peaking up of the boat speed is particularly apparent at higher wind speeds.
The best wind angles vary a bit with wind speed, so always look at the polars. Tacking upwind is typically about 41-45 deg either way. Downwind it can be 30-40 deg approx either way from directly downwind, i.e. 150-140 wind angle.
Directly downwind is 180 deg wind angle and is slow. Directly upwind is 0 deg wind angle and you briefly stop and then start going backwards!
End of nannying...
In the recent previous races the following boats (all sans options SO, like us) in Team TMSO have done well. It might be an idea to add them to your screen display:
kaechon camp 14
Maybe we can then work out how they do so well !
Update 25th Dec 2015: 8am GMT: Here is myself with Chris and Roxy this Christmas morning. Note Roxy has somehow managed a green eye to starboard and red to port ! Well done Roxy!
19:25 GMT. The start of the Sydney to Hobart race looks like being at 2am GMT tomorrow, with a following wind from 014 at 6.5kts.
The location of the start for the virtual race is outside Sydney harbour, in the open sea, which will aid the many novice virtual sailors who would have problems tacking multiple times inside the harbour trying to get out and no doubt running aground many times.
An instantaneous starting wind angle of 140 deg makes theoretical sense but the winds further offshore are much stronger. I'm thinking therefore thinking of starting with an initial wind angle of 135 and then gradually changing to 140, as the wind strengthens. The idea is being to get out into the strong winds quickly and thus higher speeds to make up for some tiny loss during the first few hours.
Anyway my course it is pre-set to 149 now with wind angle 135, noting it needs adjusting during the night (say at 3am, 4am and 5am) to gradually alter the wind angle to 144 deg, with a significant change once the wind exceeds 8.5 kts.
7:30am 26th Dec. It is now 5 and half hours since the start. During the night it seemed no one else was intending to go for 144 winds angle, but rather stuck at about 135, so I just followed along. Since 7am there has been a slight steering change to the right, but still keeping a wind angle between 135 and 140 seems most popular. My position was somewhere around 4000th after the start but has gradually improved to the 700th above. There are many avec options (AO) boats hidden behind me so I guess these will gradually overtake. Looking at the chart you can already see the band of AO boats moving ahead of the line of sans options (SO) boats.
Ranking as of 11:30am. 39428 boats in total but it looks like only about 9500 started.
12:40pm Interesting observation: After going 134 miles from the start (in last 10 hr 40min) the AO boats are 4 miles ahead.
Today was all downwind with a northerly wind, sailing was first in a SE direction, then gybing around 3pm to a SW direction. It was all rather tedious as the wind kept changing direction and it was difficult to maintain a steady 140 deg wind angle.
At 7pm the wind changed dramatically, as shown above. Wind is now from SE so changed course to due south, switched to jib sail and set up wind angle approx 50-55 deg. Unfortunately I missed the wind change by a few minutes and lost about 2 miles and about 100 places !.
I thought that a wind angle 45 deg would be best but everyone else is going a little wider, so I'm just following their idea.
10pm I got bored just following the others, so set off to the south west with wind angle 45 deg. After a few hours this seems to produce good results in terms of places so intermittently during the night tried either 45 deg or just going south. From about 5am the wind moved round a bit and 45 deg was the only option.
So good news: up from 693rd to 528th 39788 boats !
Watch the real Sydney Hobart 1516 race start below:
Watch the real Sydney Hobart 1516 race start above..
300 miles to go, approx 37 hours, with the faster boats with PRO sails about 10 miles ahead.
6:45pm Wind change coming up in 15 minutes. Strange day today. I planned to do one long leg to the south west, but changed my mind and did a dog led to the south east this afternoon; hoping for stronger winds tonight. Effect was to drop back from 518th to 746 at 7pm.
My plan for this evening is to go a little more to the south east for two of three hours and then gybe to south west. The objective being stronger winds and slightly more favourable wind directions. It did not work. See below...
10:44GMT 28th Dec 2015. Still a long way back at 588th compared with 483rd at lunch time yesterday. I've shrunk this picture sideways, with ratio 40nm:60nm to give a better impression of the shape of the sea in this area. 1 deg in latitude = 60 nautical miles.
The reason for deviating to the west of the straight line is to avoid wind angles of under 41 deg. If you look along the intended south and write down the wind directions very couple of hours you get an ideas of where to go, minimising small wind angle and trying to stay in stronger winds. Approaching the south tip there is tiny island just to the west of the orange line. You need to watch out for this obstruction and maybe turn off the display of the other boats which may hide it.
Later in the night I passed outside the small island on the southern tip. I noticed that few of the AO boats with the waypoints capability successfully managed to go via the small, 1 pixel wide, east to west channel shown in the image above. With an SO boat it is not possible to set up the approach with sufficient accuracy when arriving from the side (from the north in this case). With 10 minute increments and movements of about 1.5 miles per increment it is not feasible to set the position within the 1/12th nautical mile wide gap (500 ft wide). In this case the accuracy required is about 20ft at three different points where the course approaches the rocks.
Having rounded the corner it took a lot of effort to stay awake at the right moments to round the intermediate headland, make a 1 deg turn to the right, adjust the route to pass a narrow gap (1000ft wide) and make the final turn into Hobart, at about 5am! Still I got there eventually.
At this point my position was 521st. and this gradually this improved and I went through the narrow channel just before Hobart, gaining a few places.
This shows the Android gadget I use, some of time. It works simply as a WiFi browser, not a mobile phone as it does not have a SIM card and is locked to something I don't understand.
Results as of 10am 29th Dec 2015. I finished 478th.
Now just over 47000 boats in this Clipper Round the World virtual race simulation. Only 13400 appear to have actually taken part in this race.
Team log for next race will continue on new page...
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02/01/2016 ---- Leg 6, Hobart - Airlie Beach , 1600 miles, 6 days
To all in BRITPACK 7 team: The start for Hobart to Whitsundays race is 01:30am GMT on Saturday 2nd Jan 2016. The have given us less than 24hrs notice! Happy New Year, Eric.
They have changed the destination from Airlie Beach to Whitsundays. I don't know why.
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Page created 16 December 2015, amended 30th July 2016 ECJ (c) 2015 Copyright Satellite Signals Limited, All rights reserved.