Talk:Points of sail
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When the wind is dead astern, the Jib can be "goose-winged" to the opposite side of the boat(a whisker pole comes in handy) so that the main and jib are spread apart and both can fill. this is called sailing by the lee, and can be hazardous if not watch closely. It is also the only point of sail that does not have leeway.
Sailing goosewinged is different from sailing by the lee. Sailing by the lee is when your sail is over the upwind side of your boat - i.e. the 'wrong' side. It's often done on near when sailing lasers (with the boat tilted as well - presumably to put the centre of effort over the boat.)
The article says that running downwind is the "no go zone". The diagram appears to contradict this, as the "don't go zone". The latter makes more sense, and I suspect a typo. However, I am not a sailor, so will not presume to correct it.
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The article says that two different points of sail are the fastest: beam reach and broad reach. Does anyone know which is faster? Tom Hubbard 20:58, 17 August 2006 (UTC)
- Depends on the boat. Boats that point high and will exceed windspeed peak out on a beam reach, where they can keep the apparent wind speed high and within the pointing ability. Boats that don't point as high, and can't exceed windspeed, will probably reach top speeds with a spinnaker on a broad reach. What probably needs to happen is to find some sources that say "Boat A reaches its top speed under X conditions" and "Boat B reaches its top speed under Y conditions" so the apparently contradictory points can be supported with concrete examples. scot 21:45, 17 August 2006 (UTC)
- Some quick sources:
"4) How can it go faster than the wind?
Many sailboats can go faster than the wind. It's just a matter of decreasing the drag and increasing the thrust, or drive. If a sailboat sailed straight down wind, it could not go faster than the wind. But TriFoiler's fastest point of sail is reaching or perpendicular to the wind and then the drive does not decrease with speed." http://www.hobiecat.com/sailing/TriFoiler%20History%20Original/history_trifoiler_faq.html
"# Beam Reach - A point of sail where the boat is sailing at a right angle to the wind (wind coming from abeam). A beam reach is usually the fastest point of sail. A beam reach is a point of sail between a broad reach and a close reach." http://www.marinewaypoints.com/learn/glossary/glossary.shtml
"Broad Reach: The sails at this position should be three quarters of the way out. The broad reach is at 68� from the wind. This is the fastest point of sail for a sailboat. The final point of sail is the run." http://www.amya.org/sailmanual/part3.html
" If the wind is blowing from noon (like a clock)...the students are trying to argue that the fastest point of sail is at 9 and 3 o'clock. Since I used to race, I know that the fastest point of sail is actually between 4 and 5, and 7 and 8 o'clock (also when you are sailing a big board with a daggerboard you retract the daggerboard on this reach--called a broad reach--why?). So, who is right, and why? " http://www.madsci.org/posts/archives/apr2000/956414584.Ph.q.html
- So it looks like there are contradictory reports, which just supports my contention that it depends on the boat--and likely the wind speed, too, but speed sailors are generally interested in high wind performance. scot 21:52, 17 August 2006 (UTC)
I race boats, and will tell you that you are correct it depends on the boat, It also depends on the sails the boat is using ie..full batton, half batton, none.. but the fastest point of sail will almost always be near beam reach give or take a few degrees.
Query: It will be interesting if anyone can tell us, how close to the wind is "an efficient close hauled course" in good modern boats, eg Americas Cup? Ie, how many degrees off from head to wind?
Is someone going to correct the wiki or not... a broad reach is NOT the fastest tack, physics says the close haul is (or close reach... never heard it put that way, but OK)
- "Physics" says no such thing. Look at a set of polars some time -- reaching is much faster. It only feels faster to go upwind because of apparent wind. Susan Davis 22:29, 19 January 2007 (UTC)
[edit] Sailing re-organization effort
Take a minute to read the comments at Talk:Sailing#Re-write effort -- non how-to et seq. Some of us are working on re-organizing the sailing-related articles. See if you agree with our approach and give us some help. BTW, there is a short discussion in there on the great "fastest point of sail" controversy. Mrees1997 19:38, 29 December 2006 (UTC)
[edit] Images
Another editor replaced the reaching and running images with "better" ones, one of which might be a copyvio, and the other of which doesn't include any support for its claim to be public domain. Additionally, the existing photos have the highly desirable property that they're a matched set from the same boat in the same surroundings, and isolate the differences between points of sail rather than also introducing a contrast between boats. Adding one more photo of a modern sloop running under spinnaker, sized appropriately, might help if a free (not fair use) photo can be found, but that should be an addition, not a replacement. Susan Davis 13:29, 24 May 2007 (UTC)
- Ok, thanks for fixing the 3rd image, which previously was a red link. Addhoc 15:40, 24 May 2007 (UTC)
[edit] True and apparent wind
Please differentiate between true & apparent wind for the beam reach etc. With plain sail i.e. without a spinnaker, the fastest point of sailing in moderate winds will normally be close to a beam reach w.r.t the true wind, as stated above.
However the fastest point of sailing for truly fast sailcraft such as 18 ft skiffs with asymmetric spinnakers is around 140 deg off the true wind, at around 200% of wind speed in ~10 kt winds, at which speeds the velocity triangle shows that the apparent wind is around 10kt at 40 deg off the bow. Velocity polar diagrams for various boats are given in Bethwaite's classic book High Performance Sailing. GilesW 23:46, 9 September 2007 (UTC)
