Talk:Point of sail

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
WikiProject Sailing (Rated Start-class, Mid-importance)
WikiProject iconPoint of sail is within the scope of the WikiProject Sailing, a collaborative effort to improve Wikipedia's coverage of Sailing. If you would like to participate, you can visit the project page, where you can join the project and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Mid  This article has been rated as Mid-importance on the project's importance scale.
 

"A boat turns through the no-go zone as it tacks. " this is not correct a boat turns through the no-go zone when it gibes. — Preceding unsigned comment added by 99.25.248.185 (talk) 02:30, 31 May 2013 (UTC)

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.

======[edit]

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)
Polar performance plots, showing expected boatspeed versus wind angle for a given wind speed, are available for many sailboats, especially well-known racing classes. Exactly what angle yields the fastest speed depends on the boat, the wind, and the sails that are set. 69.196.173.44 (talk) 21:39, 28 August 2014 (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)

Sailing re-organization effort[edit]

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)

Images[edit]

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)

True and apparent wind[edit]

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)

Recovering from head to wind[edit]

"[...] if a boat comes head to wind and loses steerage, it is said to be "in irons," and may begin to travel slowly backwards. To recover, the jib (headsail) is backed to one side, and the tiller is moved to the same side."

This statement seems ambiguous and/or incorrect to me.

First of all, a boat which is head to wind and loses steerage (i.e. stops moving) will, not may begin to travel slowly backwards.

Second of all if the boat is still moving forward (from momentum) and has steerage, the statement about recovering is true, but the article states that steerage has already been lost i.e. the boat is not moving forward. However, once the boat is moving backwards the tiller should be moved to the opposite side of that on which the headsail is being backed. The key is to provide a torque on the hull by providing two side forces in opposing directions on either end of the boat. I could generate an ASCII diagram if needed.

I am not making any changes at this point but would prefer confirmation from other contributors.

Sirclicksalot (talk) 11:43, 28 June 2010 (UTC)

I agree with your second point - the tiller/rudder goes parallel with the backed jib. I think 'may begin to travel slowly backwards' is better, though, as many boats really will not do a real 'sternboard' at all, but quickly pay off onto one tack on another. This especially true for long-keeled boats (like mine), and I even have a reference for it: "Generally, the longer the keel, the more difficult steering becomes when you are going the wrong way. The same, incidentally, holds good if you are trying to sail backwards (sternboard) with your mainsail held aback by a muscular crew member. Moving astern successfully brings all your skills into play." So, let's change the tiller bit, but add a ref for the other as it's never a good idea to be too definite when you can be contradicted. --Nigelj (talk) 12:42, 28 June 2010 (UTC)
Thanks, I left "may" in and reworded the recovery passage; it's wordy but I wanted to make it unambiguous. I also changed "backed to one side" to "backed by sheeting it to one side"
I also thought of other times when the boat may be intentionally brought head to wind:
  1. When approaching a dock
  2. When recovering an object or Man OverBoard (MOB)
  3. When judging the true wind direction at the starting line before a race
There are several references to the MOB situation, so only that one makes sense to add. I'll think about whether and how these are put into the article Sirclicksalot (talk) 18:03, 28 June 2010 (UTC)
Just a note, your boat should not be head to wind when recovering a MoB. you should be in the basic hove to position which allows the sail to balance you pulling the person/object from the water into your boat.
Also, to get out of irons in dinghies, you use the manoeuvre "Getting out of Irons" usually - Happysailor (Talk) 18:08, 28 June 2010 (UTC)

Fore and aft rig vs. Square Rig[edit]

My impression from reading this article is that with the exception of a couple of places where it is discussed directly, everything refers to a fore and aft rig rather than a square rig. Are the points of sail different enough for them to be separate articles? If not, I think this article could use some clarification on the matter and more explication on points of sail with respect to square rig. 71.231.96.94 (talk) 06:49, 16 October 2010 (UTC)

Square rigged ships were extremely low performance generally ,compared to fore and aft rigged ships/yachts. Early square rigged ships could only tack at about 90 degree to the wind. Frequently they had to wait until the tide went out to make progress out of port such as London. In still air the ships were towed by rowers with the help of the tide. At sea an early square rigger with a current against it would go backwards. In shallow water ships would anchor until the wind was more favourable. The fastest square rigged ships were designed to travel fast with the wind aft by sailing them into the Southern Oceans roaring 40s. The long slim hulls and huge sail area gave high speed when running. In light air they set studding sails-lightweight sails set outboard of the standard rig to catch the light breeze but even these late square riggers were relatively poor to windward . — Preceding unsigned comment added by 122.62.226.243 (talk) 22:03, 30 September 2013 (UTC)

I still think that it would be very nice for this article to describe the points of sail from the perspective of square rigged vessels. Square rigged ships are an important part of history and many of the terms used in sailing them has lost to the modern audience. It would be nice if the wikipedia article would help them understand history better. 79.130.34.161 (talk) 18:56, 7 March 2014 (UTC)

I agree as it is this article concentrates too much on modern liesure and competition sailing and the associated sail plans.--KTo288 (talk) 23:24, 18 March 2016 (UTC)

"4.4 Making minor course changes without tacking"[edit]

This section is not only a bit of a strange thing to include but it is also incorrect. The most efficient way to turn a boat is to use crew weight and sail trim to turn while minimising rudder movement. I don't really think the section is necessary and think it should just be deleted rather then edited. 86.151.17.58 (talk) 11:07, 14 April 2014 (UTC)

Agreed. I removed the small subsection. At best it's about a course adjustment technique, stuck into a section about points of sail. Actually it made little sense, and may well be wrong in some cases. --Nigelj (talk) 12:58, 14 April 2014 (UTC)

Bug report[edit]

Can't link the German page "Kurse zum Wind" here due to Wikidata error saying it is already linked, but no other languages appear. HLHJ (talk) 14:16, 10 July 2015 (UTC)

Direction of the tack[edit]

I like this way of using "port or starboard". --Uncle Ed (talk) 13:57, 29 August 2016 (UTC)

Wonderful graphic[edit]

I don't know who made the image for the points of sail, but it is very nice. Attractive and clear. Very well presented. Phiwum (talk) 13:39, 13 September 2017 (UTC)