Junk Rig Glossary -updated and expanded, and an invitation

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  • 16 Mar 2015 08:04
    Reply # 3253355 on 3171528
    Okay, so here's a cluster of draft entries... not sure why the formatting didn't pick up:

    Aback (aka Backwinded):

    A sail filled with wind on its ordinarily lee side is said to be aback. It may be backed as a manoeuvre, or set aback by circumstance. See Back and Backwind.

    Back:

    To force or trim a sail to windward, such that it fills with wind on its ordinarily lee side. A sail in this position is said to be backed, or aback. Backing a sail may be used as a manoeuvre to force bow or stern in the direction opposite the backwinded sail, or to sail backwards. When heaving to, a backed foresail balances a close-hauled after sail. See Backwind, and alternative Aback.

    Backwind:

    To have, cause or allow wind to blow onto the ordinarily lee side of a sail. Backwinding may occur in a wind shift when pinching, causes luffing, and can be used as a manoeuvre to force bow or stern in the direction opposite the backwinded sail, or to sail backwards. Wind flow altered by a forward sail may backwind an after sail. See Back, and alternative Aback.

    These declare Aback to be standard over backwinded where they overlap.

    Does this cover the ground?

    I've not included back and veer (wind shifts)... but guess I should.

    Dave Z

  • 16 Mar 2015 06:21
    Reply # 3253330 on 3171528
    Hi Arne,

    English isn't for the faint of heart. This country boy from Alaska struggles mightily.

    One of the joys of usage (and the terror of glossarians!) is that sailors were a mostly uneducated polyglot of ruffians with a flair for local color. The result is usages that are all over the place in terms of consistency, many to most of which have equal claim to legitimacy.

    Naval and yachting traditions tend to be more concerned with propriety and exactitude, while working sail traditions seem to be more local and easy going.

    Subtle distinctions - as between verb/adjective pairs such as back/aback vs backwind/backwinded - were probably lost on most sailors who ever lived. It was likely all the same to them. It's only in the last few generations that we have anything approaching aerodynamic theory!

    To tell you the truth, I don't really have my heart in discerning the finer points... I rather like the free and easy use of terms which convey the general meaning, even when it's a somewhat loose fit.

    When aboard other boats, I often find that there's a verbal equivalent of 'house rules'... the skipper sets out what she or he means by such and such, and that's what we use aboard the good ship under their command. Understanding has never suffered, while each variant seems rooted in one lineage of tradition or another.

    An example would be yard vs lug... technically, the JR is a standing lug sail, so the spar at its head is a lug. But the HM tradition calls it a yard, which some would fight to the death, maintaining that a yard "is NOT a fore-and-aft spar". Me, I'm agreeable... I'll call it whatever we agree to call it.

    So I see the purpose of the JRG to set our own 'house rules' (agree upon some standards), where helpful or necessary. And tread with a light touch elsewhere, hinting at the rich latitude of our sailor's language.

    That's my approach, anyway.  8)  It sure makes for interesting work!

    Dave Z


    PS. Annie, 'manoeuvre' it is (uh-oh... now we've offended my spell-checker!).

  • 15 Mar 2015 17:30
    Reply # 3252923 on 3252909
    ueli lüthi wrote:

    i think, there's some overlap on your ashiki as soon as you ease the sheets to let the sails stay a fair amount to the leeward side. the wind doesn't know about the centerline of your boat. it only 'sees' the sails – and they overlap each other…

    ueli

    I think the theory only holds when close to the wind. As I understand it, when reaching the jib is not in the flow ahead of the main, it does not benefit from the upwash and accelerated flow.
    Last modified: 15 Mar 2015 17:31 | Anonymous member
  • 15 Mar 2015 17:28
    Reply # 3252922 on 3171528
    Anonymous member (Administrator)

    .. Backwind, being back-winded, backing, being backed, with the jib aback...

    Sailing terms, and not least English sailing terms can easily confuse an old farm boy from Norway, even though he grew up on a Massey Ferguson, made in England.

    Now I have browsed the web: It appears that a few use the term backwinding a sail where most others seem to use the term backing the sail or keeping/holding the sail aback. Backwinding seems mostly to be describing the situation when the wind from one sail blows into the one aft of it.

    Below you find a few strings of text, cut from the web:

    “Using the back winded jib to get through the tack,...”

    «One sail backwinds another when it directs its wind onto the leward side of the other sail. «

    “.. Ah, nice graphic showing why the luff of the main will back-wind and ruin the performance...”

    “...Backwind TIP
    • Closehauled, a jib will sometimes backwind the mainsail, causing it to luff along the leading edge. This is normal; if there's 1 to 2 feet of backwind, your trim is likely fine. If there's a lot of backwind, the jib may be overpowered; try moving the jib-sheet lead aft or outboard. You can also try rolling in a portion of the jib....”

    Jib aback...
    Here are a few examples  from the online Oxford Dictionary:

    • Once the boat has tacked the jib will be aback.
    • The wind came now from this side, now from that, determined to catch the sails aback.
    • Peter holds the jib aback until our bow swings across the wind.


    From RYA Sail training:

    “The principle of heaving-to is that the boat is set up with its jib aback, driving its bow to leeward, while the main is filling conventionally, shoving the stern downwind and balancing out the headsail. The rudder serves as a kind of fine tune, leaving the boat in a state of equilibrium lying about 45 degrees off the wind and waves.”

    Conclusion:
    I am sooo glad I don’t have to fit this into the JRG...

    Good night and good luck,
    Arne

     PS: I also spotted diagrams with hove-to boats with a "backed jib" note on the jib and "jib aback" on others...

    Last modified: 15 Mar 2015 17:30 | Anonymous member (Administrator)
  • 15 Mar 2015 16:41
    Reply # 3252909 on 3252688
    hi gary
    Gary King wrote:I see what you guys are saying about the lack of overlap in junk schooners, but I'm wondering why the foresail still appears to pull harder than the main if no slot benefit…

    i think, there's some overlap on your ashiki as soon as you ease the sheets to let the sails stay a fair amount to the leeward side. the wind doesn't know about the centerline of your boat. it only 'sees' the sails – and they overlap each other…

    ueli

  • 15 Mar 2015 07:04
    Reply # 3252688 on 3239645
    Darren Bos wrote:

    ..Marchaj and Gentry are a much better place to learn about these things compared to many other sources which rely on older theories which are incorrect in whole or in part.  It is ironic that we are putting a bunch of thought into this, since as Chris points out we can't really benefit from the effect with most Junk platforms (with the exception of the Split Junk Rig, which probably sees some benefit).  However, it is cool and part of an understanding of aerodynamics which when applied to Junk rigs can make them better.

    I see what you guys are saying about the lack of overlap in junk schooners, but I'm wondering why the foresail still appears to pull harder than the main if no slot benefit - as in what Gentry postulates (the bermudan main causes the jib to experience more lift). 

    I get the sneaky feeling my main is causing the foresail to stress more, it certainly suffers more (one tear already - though that maybe because it feels all the pitching).

  • 15 Mar 2015 02:20
    Reply # 3252590 on 3171528
    I would tend to sail that a sail is 'backwinded' implying either by another sail or a sudden shift in the wind.  And yes, would backwind the foresail on a junk to guarantee a tack or a headsail on a BR to heave to.

    Your latest definition seems very acceptable to me.  To save me the effort, would you mind spelling maneuver, manoeuvre, please :-0

  • 14 Mar 2015 09:16
    Reply # 3251992 on 3249315
    Arne Kverneland wrote:

    Is backwinding just synonymous with luffing, or is the term only used with sails in front of each other?

    Hi Arne,

    As usual, I get a whole range of similar but vaguely incompatible results from various sources.

    These seem to be the general candidates for backwinding:

    1. to divert wind against the lee side of (a sail) from another sail.

    2. to set (a sail) so that the wind is on what would ordinarily be the lee side, as for turning the bow of a boat away from the wind.

    3. to blanket (another sailing vessel) by spilling wind from the sails of one vessel onto the lee side of the sails of the other.

    4. to have wind blow against the lee side of a sail.

    I'm having trouble picturing #3! Must happen in a crossing situation with the victim to leeward? As it seems rare and obscure... I'm thinking skip it in the JRG entry? Any racers want to stick up for its inclusion?

    The last case (from http://www.nauticed.org/freesailingcourse-m2-3) draws a fine distinction between luffing and backwinding, claiming that backwinding begins just before luffing.

    Certainly, luffing implies backwinding, though not always the reverse.

    Anke and I use the term mostly in sense #2 when 'backwinding the main or mizzen' to force the bow or stern off to one side or 'sail' backwards. We used to use it when heaving to with a 'backwinded headsail'.

    One fun maneuver is (if caught falling off on a missed tack) is to backwind a foresail and literally sail the bow around, keeping it trimmed appropriately close hauled to the wind. Only manage about half the time, but don't have to practice, often.  8)

    How about this:

    Backwind:

    To cause or allow wind to blow onto the ordinarily lee side of a sail. Backwinding may occur when pinching, causes luffing, and can be used as a maneuver to force bow or stern opposite the backwinded sail, or to sail backwards. Wind flow altered by a forward sail may backwind an after sail.

    Dave Z

    Last modified: 14 Mar 2015 09:50 | Anonymous member
  • 12 Mar 2015 13:47
    Reply # 3249582 on 3171528

    Quite right Arne, backwinding occurs when a sail luffs due to air deflected by a sail ahead. I wonder if this arises with flat sails, or only with cambered ones?

  • 12 Mar 2015 10:11
    Reply # 3249315 on 3171528
    Anonymous member (Administrator)

    The terms luffing and backwinding

    The term luffing a sail describes what happens when you pinch too closely to the wind, as shown here.

    I also read about the term backwinding. It seems to be much the same as luffing the sail, but this time as a result of over-sheeting the sail in front of it. “The mainsail is backwinded by the foresail”, something like this.

    Is that so? Is backwinding just synonymous with luffing, or is the term only used with sails in front of each other?

    I hope some of you can straighten this up so the term backwind can find a place in the JRG.

    Thanks,
    Arne

     

    Last modified: 12 Mar 2015 18:55 | Anonymous member (Administrator)
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