climenuts

Jib Top for Cruising in the PNW?

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TL;DR: I'm wondering what the feasibility/use case is for a Jib Top on my C&C 29mk2 for Cruising in the PNW. What are your thoughts on the performance of a Jib-top over the barberhauled Genoa? Is it worth the extra effort of potential sail changes single-handed?

I'm primarily cruising from Vancouver to the Gulf Islands and back and I find myself close/beam reaching most of the time while crossing the Strait of Georgia. Apparent wind angles typically range from beam on to ~10 degrees off close hauled on these crossings depending on where I'm headed and wind strength.

I'm finding I've got a pretty big gap between my brand new 135% Genoa barberhauled outside the lifelines and my Asymmetric Spinnaker which came with the boat which has a wire luff and seems to have a cut suitable for closer wind angles. In ~3-8kts I can carry the A-sail at about 85 degrees true but above that I have to bear away or go back to white sails.

I've been thinking it might be worth getting my old 135% Genoa re-cut as a jib top to fill in this gap. A lot of the time I won't beat out of English Bay or Trincomali channel due to time constraints with tides but I prefer to sail across the strait. This means I'm not really concerned about the lack of close hauled performance and I'm not super worried about changing the headsail once in the gulf islands where I'm likely to be beating to the next anchorage. I'm typically taking my headsails down while at anchor rather than leaving them furled with my UV cover hoisted.

 

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jib tops are forgotten sails, but they are really nice for the most part and they allow for great visibility to leeward.

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4 minutes ago, Editor said:

jib tops are forgotten sails, but they are really nice for the most part and they allow for great visibility to leeward.

The visibility to leeward wasn't something I really considered... I suppose that help me avoid having to lean over the leeward rail and look around every few minutes.

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Have your sailmaker sew an upper clew onto your standard cruising Genoa so you can swap back and forth, if it matters enough to you. There will be some flapping but you're cruising. 

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For your use case a Jib Top would be the perfect sail.  Set up a tweaker and use the spinnaker sheet and you will be all set. A JT on a furler would be a GREAT way to beam reach through life.

MS

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I end up sheeted in too far for a JT coming home from Silva Bay about 60% of the time.

Also, cutting the bottom off your sail just makes the sail smaller, a real JT has the same area as your Genoa and would typically have a fuller shape than an all-purpose Genoa.  What you are talking about is more of a Yankee jib.

 

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1 hour ago, climenuts said:

The visibility to leeward wasn't something I really considered... I suppose that help me avoid having to lean over the leeward rail and look around every few minutes.

it makes sailing a lot more relaxing!

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16 minutes ago, Schnick said:

I end up sheeted in too far for a JT coming home from Silva Bay about 60% of the time.

Also, cutting the bottom off your sail just makes the sail smaller, a real JT has the same area as your Genoa and would typically have a fuller shape than an all-purpose Genoa.  What you are talking about is more of a Yankee jib.

 

It's tricky b/c under PHRF, they just care about the LP%, whereas with ORC, you need to keep the sail area the same to avoid penalizing the rating.

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Same thing!  If your LP is the same you will have, within a bit, the same area.  That's why PHRF uses LP to calculate area.

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I'd say no. Giving up sail area in BC seems wrong. You're close enough to close hauled that easing the sheet isn't that big deal.

To me jib tops are good for ocean races where you don't want a genoa scooping up the waves and you're on a reaching course.

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Jib tops are designed to be used with a staysail/ double head rig. IMO a good cruising combo   Very powerful reaching especially in a sloppy sea state. Drop the staysail if the wind increases and you are still good. The visibility as mentioned above is a plus. The jib top is generally sheeted to the rail

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Couple of thoughts.  As already mentioned, the Jib Top has more draft then a genoa, and that draft is farther forward.  Its also designed with more twist to the leech, to match the twist of the main when reaching.  Finally, they are designed as medium and higher wind sails.

That's what makes them valuable sails offshore, where your course is more constant, and the windspeed and direction is also more constant.  In your case, in the PNW, where summers are light air, and windspeed and direction are less constant, I'm not sure a jib top is a good use of your money.  You could have a high clewed genoa say around a 145, which would give you the better visibility of a Jib Top, along with a high clew to allow better sheeting angles/control of twist when reaching, while still retaining the draft depth and position of a genoa, so that you can still go upwind with it when you need to without have to change sails...

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My sailmaker made a high clew 135 genoa for my cruising. It is very handy. Easing the sheet onto a reach or run does not require moving the block to maintain shape. It is cut flat to be weatherly when hauled in tight. Block is on the rail far aft - aft of the main winches. Very handy in the shifty and light Philippine conditions. Furls to a reasonable hanky for squalls. Without race crew on the rail the 135 is plenty for me.

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Old School double-head rigs back when lots of boatsD3855042-39CA-4232-B45D-951502C6A6D9.jpeg.f3b34f6843887d2e790b8799a4aa4ec3.jpeg raced with them.

BE26C39C-0EAE-4CDF-8E0B-40C4FECC7128.jpeg

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Have you spoken to a good sailmaker/designer about it? If not, drop me a PM and I'll send you one that I'd trust to give you good advice.

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Overlap is a silly concept.

Ever sailed a Windsurfer? Nearly all the load is on the forward hand, quite close to the mast. This is because that is where the lift is generated. Almost all the lift, the driving force, of any sail is within a foot or two of the leading edge.

Overlap is like wetted surface: it is drag. The force difference between the windward and leeward side of the overlapped area, which means the lift vector in that area of the sail, is athwartship: makes you heel, but does not make you go forward.

My boat is a good light air boat. An Olson 40. I never race it, it is purely for cruising. My headsail is a lapper: the clew is high, about boom height, and the clew and leech barely MISS the mast -- there is zero overlap. In this picture, its blowing 6 knots, and we are going 6.5 knots close hauled. 

Note that because the clew is (barely) forward of the mast, I use the windward sheet as a barber hauler, so the "effective" track location is on the cabin top, but no holes in the deck, easy to adjust the lead in and out using the windward sheet.

Also, tacking is easy: I ease the old sheet about 3 feet, and grind the the new about 3 feet. Sail is always in control, never thrashing itself on anything, no sheets tearing out of the cockpit, no snapping sheets, no jarring on the sheet, much safer.

Another cool thing: the lapper is fully battened. This means it is easy to deal with on hoist and drop. Also, one batten is diagonal from the clew to the headstay, so I can head DDW with the jib wing-on-wing without needing a whisker pole.

Since the sail is carbon, the headstay dyneema, and the soft hanks are dyneema, it is light and low friction, so easy to hoist and drop. This means no roller furler is required. I have a sail cover for the lapper, so I leave the sail on the headstay when moored, so it is easier in every way than furling, and it will last longer, and the boat lies quietly at anchor without tacking. Tacking at anchor is caused by windage forward, by roller furled headsails.

IMG_6377.jpeg

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Small overlap means when you reaching you can get the mainsail well out without it  backing and keep the boat balanced. Also visibility looking forward is a great safety benefit when short crewed and short on lookouts. Came across the  North Atlantic with high cut jib, staysail and a 3 reef main.  We handled everything from 5 to 40 knots. 

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The other advantage of a good smallish jibtop is it can be an excellent heavy air downwind sail when you have to get out of Dodge in a hurry. A couple of reefs in the main, jibtop on the pole and you're good to go.

Which was Tougher- Whitbread or Volvo Race! - Ocean Globe Race

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Jib Tops are very under rated.  2017 SoCal 300, I made my then boss, get his sailmaker to root around in the sail storage locker for an hour to dig out the JT. It was a necessary and useful tool.

IMG_0416.jpg

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On 4/15/2020 at 11:06 AM, climenuts said:

TL;DR: I'm wondering what the feasibility/use case is for a Jib Top on my C&C 29mk2 for Cruising in the PNW. What are your thoughts on the performance of a Jib-top over the barberhauled Genoa? Is it worth the extra effort of potential sail changes single-handed?

I'm primarily cruising from Vancouver to the Gulf Islands and back and I find myself close/beam reaching most of the time while crossing the Strait of Georgia. Apparent wind angles typically range from beam on to ~10 degrees off close hauled on these crossings depending on where I'm headed and wind strength.

I'm finding I've got a pretty big gap between my brand new 135% Genoa barberhauled outside the lifelines and my Asymmetric Spinnaker which came with the boat which has a wire luff and seems to have a cut suitable for closer wind angles. In ~3-8kts I can carry the A-sail at about 85 degrees true but above that I have to bear away or go back to white sails.

I've been thinking it might be worth getting my old 135% Genoa re-cut as a jib top to fill in this gap. A lot of the time I won't beat out of English Bay or Trincomali channel due to time constraints with tides but I prefer to sail across the strait. This means I'm not really concerned about the lack of close hauled performance and I'm not super worried about changing the headsail once in the gulf islands where I'm likely to be beating to the next anchorage. I'm typically taking my headsails down while at anchor rather than leaving them furled with my UV cover hoisted.

 

Wide range of responses here, but no one is considering your present situation/boat/sail plan. There is probably a big jump in sail area between your asso & your 135 genoa. This is the first thing to consider -actual sail size. Then look at wind angles you want to fly this sail in. Then talk to a sailmaker. A Jibtop of the same overlap will only be slightly faster than your genoa - a little better shape, & sail area up higher (for same overlap). What is overlap/sail area of the asso?

 So until you give us dimensions of asso, I think there are two choices: replace 135 with a 150 high clewed sail or consider a free flying jibtop(?) Code 0 (?) depending on how close winded you need it to go. Set this on a bottom up furler forward of headstay, 2 x 1 halyard.

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5 hours ago, El Boracho said:

That ^^^ looks like it was re-cut from a mainsail.

Your willingness to expose your stupidity is impressive.

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On 4/15/2020 at 9:41 PM, Professor Fate said:

Old School double-head rigs back when lots of boatsD3855042-39CA-4232-B45D-951502C6A6D9.jpeg.f3b34f6843887d2e790b8799a4aa4ec3.jpeg raced with them.

BE26C39C-0EAE-4CDF-8E0B-40C4FECC7128.jpeg

Ya Bruce King was big on double head rigs.  I raced on an Ericson 37 back in the day.  Double head rig was slow except in a narrow wind range and angle of about 12 to 16 true and 55 to 70 ish true wind angle.  Switched to a standard genoa after one season, was faster upwind in all wind speeds.

Jib top probably ain't worth it for your application.  Others have said they are usually sails that are for close reaching in breeze on a distance ocean race so waves don't blow out the foot of a standard genoa.  There are adaptations to this that work, if your headsail is adaptable, you can have another sheet ring some distance up the leech to put the sheet attachment higher.  Also back in the day, some headsails had a foot loop sewn in where you could put a halyard to hoist the foot up outta the water.  Worked ok too as long as you had the foot up high enough.

Sounds like the range of wind you are looking to fill is getting more punch in softer breeze close reach.  A recut 135% is not gonna do that.  You need more sail area, like a 150% 

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I have an idea, do not touch your standing inventory, you might need it.

Go on line and look for a USED JT for your boat. Compare it against an outboard lead for your 135%. You might like one over the other.

Sail Safe!

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17 hours ago, P_Wop said:

The other advantage of a good smallish jibtop is it can be an excellent heavy air downwind sail when you have to get out of Dodge in a hurry. A couple of reefs in the main, jibtop on the pole and you're good to go.

Which was Tougher- Whitbread or Volvo Race! - Ocean Globe Race

Itsa winch farm!

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12 hours ago, Hitchhiker said:

Your willingness to expose your stupidity is impressive.

Heh, just blind. Yesterday when I looked at it I though is was wing-on-wing with bizarre draft stripes and battens . Today on the big screen I see it is on the other side.

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7 hours ago, SailRacer said:

I have an idea, do not touch your standing inventory, you might need it.

Go on line and look for a USED JT for your boat. Compare it against an outboard lead for your 135%. You might like one over the other.

Sail Safe!

Great idea, but how many C&C 29 Mk IIs do you think have had a JT even made for them?   Maybe there is some more modern race boat with similar rig dimensions?

 

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Isn't the J dimension on that boat pretty big?  Recutting an old 135, with heavy forward draft, may do just the trick.  Still a bunch of sail area forward.  Likely wouldn't be a true JT, but may be worth it.

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29 mkii lacks both form stability and rig size, so first step in this process is to adjust your expectations, there is a reason there are about 3 of these in the whole province.

Second step is to recognize that a dollar spent below waterline is worth 10 dollars in sails, so make sure you have a folding prop and then budget $500/year for a diver to clean the bottom, in Vancouver that will get your boat done every second month.  Combination of these two is worth an hour on a typical crossing of Georgia Strait in a 29 footer.

Final item, more sail = more power.  A 135 genoa beats that same genoa cut down with a high clew, which typically reduces the sail to a 125 or so (measure the new LP).  The real solution here should be a 155 genoa for that boat.  If you then need still more oomph, the standard sized asym kites from North Cruising Direct are good in this application.

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On 4/15/2020 at 11:27 AM, jackolantern said:

Have your sailmaker sew an upper clew onto your standard cruising Genoa so you can swap back and forth, if it matters enough to you. There will be some flapping but you're cruising. 

I really don't want any flapping on my brand new Genoa...

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On 4/15/2020 at 12:13 PM, Schnick said:

I end up sheeted in too far for a JT coming home from Silva Bay about 60% of the time.

Also, cutting the bottom off your sail just makes the sail smaller, a real JT has the same area as your Genoa and would typically have a fuller shape than an all-purpose Genoa.  What you are talking about is more of a Yankee jib.

 

I can picture in lighter airs with more waterline the wind angle would be too far forward. With a hull speed of 6.3kts the apparent wind angle is a bit more forgiving for me in my experience.

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On 4/15/2020 at 9:48 PM, PaulinVictoria said:

Have you spoken to a good sailmaker/designer about it? If not, drop me a PM and I'll send you one that I'd trust to give you good advice.

I've spoken to North who I've bought a new Main, 135% Genoa, and two symmetric kites from this past year. They told me not to bother with a new JT but recutting the full shaped old Genoa may make sense.

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On 4/16/2020 at 4:49 PM, longy said:

Wide range of responses here, but no one is considering your present situation/boat/sail plan. There is probably a big jump in sail area between your asso & your 135 genoa. This is the first thing to consider -actual sail size. Then look at wind angles you want to fly this sail in. Then talk to a sailmaker. A Jibtop of the same overlap will only be slightly faster than your genoa - a little better shape, & sail area up higher (for same overlap). What is overlap/sail area of the asso?

 So until you give us dimensions of asso, I think there are two choices: replace 135 with a 150 high clewed sail or consider a free flying jibtop(?) Code 0 (?) depending on how close winded you need it to go. Set this on a bottom up furler forward of headstay, 2 x 1 halyard.

The a-sail is ballpark 150% judging by where the clew ends up when fully sheeted in light air. I haven't measured it because I don't use it when I race and don't want my rating to be affected by it.

The boat is overpowered pretty easily with the 135% Genoa as it is. Anything more than 15kts and I put up my 105% jib when single-handed. I think the PHRF code 5 Genoa is 150-155% for this boat but it would be too unwieldy for me single-handed; especially with the babystay in the mix during tacks.

 

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On 4/17/2020 at 1:52 PM, oldskool said:

Isn't the J dimension on that boat pretty big?  Recutting an old 135, with heavy forward draft, may do just the trick.  Still a bunch of sail area forward.  Likely wouldn't be a true JT, but may be worth it.

I'm not sure what to compare it to but it's 11'4". Definitely a headsail driven boat. The thought on the forward draft with the bagged old Genoa was my thinking.

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On 4/18/2020 at 7:24 AM, Tyler Durden said:

29 mkii lacks both form stability and rig size, so first step in this process is to adjust your expectations, there is a reason there are about 3 of these in the whole province.

Second step is to recognize that a dollar spent below waterline is worth 10 dollars in sails, so make sure you have a folding prop and then budget $500/year for a diver to clean the bottom, in Vancouver that will get your boat done every second month.  Combination of these two is worth an hour on a typical crossing of Georgia Strait in a 29 footer.

Final item, more sail = more power.  A 135 genoa beats that same genoa cut down with a high clew, which typically reduces the sail to a 125 or so (measure the new LP).  The real solution here should be a 155 genoa for that boat.  If you then need still more oomph, the standard sized asym kites from North Cruising Direct are good in this application.

I know the mki has worse form stability, maybe you're thinking of that?

Folding prop is on the list for my next haul-out and I scrub the boat myself throughout the summer. Saying it'll save me an hour on a 4-5 hour crossing seems a bit rich.

I don't think it's an area issue, I think it is an issue with garbage shape once eased even with a barberhauler on the rail. Past ~15° off close hauled you can't maintain a slot.

I understand a 155% Genoa is fairly common on this boat but they are decksweepers using every inch of the Genoa track which would suffer even more when starting to ease the sheet. I am also single-handing all the time and tacking a 155% Genoa around the babystay would be a total nightmare.

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You don’t really need the babystay when you can carry the 155.  You need it to control mast pump when you’re carrying the number 3 and there’s waves /chop.  I totally did away with mine on my S2 9.1.  Maybe make the babystay detachable?  It’s not like the mast is a noodle.  You can get all the shape control you want with pre-bend and backstay...

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On 4/17/2020 at 7:48 AM, bgytr said:

Itsa winch farm!

Probably $200k in winches alone. Should have spent a bit more on the keel.

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My S-40 came with two North Jibtops.  Sold one to a friend on his X-119.  Kept the carbon one.  They are impossible to fold with the battens in and move around the boat, but in the right windy conditions they are amazing (and now forgotten) sails.  The previous owner managed 26.7 kts with it up on a Honolulu to Kauai race.  The fastest I've ever sailed was 27.1 kts with the Jibtop up on a ULDB70 ripping down the coast from Hong Kong to Vietnam after we had blown up literally all the kites.

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Had an old uk tape drive jibtop that I used for cruising in a j-33.  Excellent sail.  Kicked ass a few times at rtc as well.

 

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Where I normally sail, a #1 is superfluous, but I have a really nice full size jibtop. I’m wondering, can I cut her down to the #2 size? Then I can carry for some of the ocean races (I’m rated for a #2)

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On 4/19/2020 at 9:53 PM, climenuts said:

I really don't want any flapping on my brand new Genoa...

Have the sailmaker throw in a few cringles in there too. No need for flapping. But...

Re: your original query about adding a jib top to your inventory:
My take for cruising is a simple 4 sail inventory:

  • Main, of course.
  • High-clewed genoa.
  • Working jib with reef points.
  • Cruising spinnaker.

The high-clewed genoa is not a dedicated jib top. Just get the foot high enough off the deck so that you can see boats to leeward of you and the clew high enough that you don't need to move the fairlead [much] when you crack off.

Working jib with angled reef points so the reefed sail sheets to the same position as the unreefed sail. Reefed, it becomes a small #4/storm jib.

Spinnaker should tend toward a reaching cut as opposed to deep running. You want to narrow that inventory gap between the high-clewed genoa and the spinnaker.

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8 hours ago, Somebody Else said:

Have the sailmaker throw in a few cringles in there too. No need for flapping. But...

Re: your original query about adding a jib top to your inventory:
My take for cruising is a simple 4 sail inventory:

  • Main, of course.
  • High-clewed genoa.
  • Working jib with reef points.
  • Cruising spinnaker.

The high-clewed genoa is not a dedicated jib top. Just get the foot high enough off the deck so that you can see boats to leeward of you and the clew high enough that you don't need to move the fairlead [much] when you crack off.

Working jib with angled reef points so the reefed sail sheets to the same position as the unreefed sail. Reefed, it becomes a small #4/storm jib.

Spinnaker should tend toward a reaching cut as opposed to deep running. You want to narrow that inventory gap between the high-clewed genoa and the spinnaker.

I like the sail inventory and see how it applies to a lot of people. In the BC South Coast the issue is I'm always beating or running in the various channels (with the exception of the previously mentioned Strait of Georgia crossings). This has led me to focus the Genoa on upwind performance; especially when my beat VMG is 3-4kts towing a dinghy. I also get my best run VMG pointing DDW in anything over ~10kts so I use the Symmetric kite a lot.

 

Here's a 'shitty' polar set I made myself by interpolating from a C&C 25 and C&C 30's polars. Has been pretty accurate to my past experience but there's a couple wonky crossovers.

C&C 29mk2   Hull Speed 6.33        
 (from Hull Speed Interpolation of C&C 25 and C&C 30 Polars)          
TWS 6 8 10 12 14 16 20
TWA 43.8 42.9 43.4 42.5 41.7 41.5 42.2
AWA 26.8 27.7 29.1 29.5 30.2 31.1 33.4
AWS 9.21 11.73 14.14 16.46 18.50 20.51 24.44
VMG (Beat) 2.81 3.31 3.70 4.03 4.13 4.18 4.15
BS (Beat) 3.90 4.52 5.09 5.47 5.53 5.57 5.60
52° 4.32 5.07 5.59 5.86 5.99 6.05 6.06
60° 4.60 5.37 5.79 6.02 6.16 6.24 6.27
75° 4.82 5.56 5.94 6.16 6.35 6.50 6.65
90° 4.78 5.64 6.09 6.32 6.50 6.67 6.98
110° 4.89 5.77 6.20 6.54 6.84 7.07 7.35
120° 4.74 5.67 6.15 6.51 6.85 7.16 7.60
135° 4.34 5.27 5.93 6.30 6.03 6.98 7.63
150° 3.74 4.65 5.44 5.98 6.31 6.63 7.25
VMG (Run) 3.24 4.03 4.74 5.40 5.88 6.22 6.82
TWA 148.5 152.2 153.9 168.5 180.0 180.0 180.0
AWA 112.9 124.0 130.1 159.0 180.0 180.0 180.0
AWS 3.40 4.50 5.75 6.69 8.12 9.78 13.18
BS (Run) 3.80 4.56 5.28 5.51 5.88 6.22 6.82
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On 4/21/2020 at 10:29 AM, Caca Cabeza said:

Probably $200k in winches alone. Should have spent a bit more on the keel.

I never TRULY realized and appreciated just how damn expensive winches were until I had to replace a couple...

I hate them.

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7 minutes ago, Floating Duck said:

I never TRULY realized and appreciated just how damn expensive winches were until I had to replace a couple...

I remember Raul Gardini trying to put it in perspective for a young Italian journalist on one of the later IOR Maxis, Il Moro di Venezia III.  Standing on deck he started pointing to each winch and said: "Fiat, Fiat, Alfa Romeo, Alfa Romeo, Maserati, Fiat, Maserati, Lancia..." etc... 

The poor boy's jaw dropped several centimetres as the truth sank in.

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2 hours ago, P_Wop said:

I remember Raul Gardini trying to put it in perspective for a young Italian journalist on one of the later IOR Maxis, Il Moro di Venezia III.  Standing on deck he started pointing to each winch and said: "Fiat, Fiat, Alfa Romeo, Alfa Romeo, Maserati, Fiat, Maserati, Lancia..." etc... 

The poor boy's jaw dropped several centimetres as the truth sank in.

Back in the day, say 1993-4, I was at a Finance all-hands for Intel. We were talking about yields on chips. Exciting stuff, not.

There was a factory VP on stage, he had a 6" wafer, with x486s etched on them, but for some reason, lost that wafer (bad). His words. "Here's a brand-new corvette." (Yes, the average yield on a 486 wafer was around $60k net to Intel)

Then, he had the normal tray used in the factory, this thing is about 12-14" long, holds like 50 of these wafers. Also dead. His words "and here's a parking lot of corvettes"

Auto-analogies work really well!

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37 minutes ago, Raz'r said:

Back in the day, say 1993-4, I was at a Finance all-hands for Intel. We were talking about yields on chips. Exciting stuff, not.

There was a factory VP on stage, he had a 6" wafer, with x486s etched on them, but for some reason, lost that wafer (bad). His words. "Here's a brand-new corvette." (Yes, the average yield on a 486 wafer was around $60k net to Intel)

Then, he had the normal tray used in the factory, this thing is about 12-14" long, holds like 50 of these wafers. Also dead. His words "and here's a parking lot of corvettes"

A few years ago, as a chip guy myself, we designed a really tiny MPU for the IoT.  Our fab partner was getting 2,000+ from an 8" wafer, and that was on 180nm mixed signal.  They produced lots of expensive silicon dust when dicing them.  He announced one day that he was getting a yield of 101.5%.  WTF?  Yes, our individual dies were so small he was counting some good ones round the edges.  Rather than testing all the dies on-wafer, we packaged them all, and tested later.  Cheaper.

In our case the devices were each sold for so little that the whole wafer was worth the same as a old and abused third-hand Skoda.

Back to your usual programming.

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