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Foiling Monohull - what would it look like?

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 t

This is the prototype put out by Team UK, Looks like it might kill someone 

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2 hours ago, Sam_rosenbaum said:

 t

This is the prototype put out by Team UK, Looks like it might kill someone 

Gawd you've got several months of reading to get through before posting...

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On 9/4/2018 at 1:24 PM, dg_sailingfan said:

We did not dialups in the AC 50?

High-performance boats do not preclude dialups - there was a massive dialup between the trimaran and catamaran at the start of race 1 of the 33rd AC. 

A dialup is a tactic you use in a windward start.  I don't see how it makes a lot of sense for a reaching start, because the boat closer to the line has a huge advantage.  You'd get the hook, take them up, and then peel off for the line before coming to a stop in a dialup.  Crossing the windward boundary of the starting area gets you both offsetting penalties, so it's not like taking your opponent to the course side of the start line and then ducking back to start before them.

The 36th AC will have windward starts, so expect dialups.

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7 minutes ago, Basiliscus said:

High-performance boats do not preclude dialups - there was a massive dialup between the trimaran and catamaran at the start of race 1 of the 33rd AC. 

A dialup is a tactic you use in a windward start.  I don't see how it makes a lot of sense for a reaching start, because the boat closer to the line has a huge advantage.  You'd get the hook, take them up, and then peel off for the line before coming to a stop in a dialup.  Crossing the windward boundary of the starting area gets you both offsetting penalties, so it's not like taking your opponent to the course side of the start line and then ducking back to start before them.

The 36th AC will have windward starts, so expect dialups.

Well, at least that is what they keep saying. AC 33 did not have "Foils" so there wasn't a huge problem back then, these new AC 75 Class Boats will have these sort of canting foils. Imagine one of the foils hit you when you in the Start Box.

Having Pre-Start Dialups with the foils they have is a very undesireable Result. I'm totally agreeing with the User "Boybland". They should keep these foils down until the Start Gun if the want windward starts otherwise it gets too dangerous.

We already had a Start Collision between former Land Rover BAR and SBTJ during the AC Qualifiers of AC 35. Given how hard these Helmsman will push their boats during the Pre-Start I'm getting very concerned about this.

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FWIW, Patrizio Bertelli in the latest La Stampa interview said there’ll be circling, with both foils in the lower (docking) position

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But the Noob/sock puppet is concerned, very concerned, so hit the panic button - or call the whole thing off!!

Try informing yourself a bit dg-s, note that AC boats race under different rules from all others, these rules take into account (as far as pos') the speed and the pointy bits associated with foiling - heard of the 'Virtual Diamond'? And no,  that has nothing to do with Indiana Jones.....

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2 hours ago, Xlot said:

 

FWIW, Patrizio Bertelli in the latest La Stampa interview said there’ll be circling, with both foils in the lower (docking) position

Now that makes more sense in the Start Box.

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Then again using the foils to attack each other 'Robot Wars' style would probably bring in a whole new audience!?

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5 hours ago, nav said:

Then again using the foils to attack each other 'Robot Wars' style would probably bring in a whole new audience!?

Basher tried that last time, didn't work out so well :ph34r:

 

Surely this was a dialup? (and a clean out!)

 

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1 hour ago, hoom said:

Basher tried that last time, didn't work out so well :ph34r:

 

Surely this was a dialup? (and a clean out!)

That is not a dial, it's a hook.

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13 hours ago, nav said:

Then again using the foils to attack each other 'Robot Wars' style would probably bring in a whole new audience!?

 

7 hours ago, hoom said:

Basher tried that last time, didn't work out so well :ph34r:

 

That was a simple wrestling move - (I'd post photos of face sitting but....... :o),  much better weapons systems this time!

 

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8 hours ago, Boybland said:

That is not a dial, it's a hook.

Yes but after the hook is established isn't the luff all the way up to head-to-wind a dialup? I always thought that counts as a dialup.

 

But also the start of the sequence, what got Jimmy in the shit was he predicted ETNZ was going to tack immediately & attempted to close the gauge to block the tack -> forcing a conventional dialup or gybe but Orifice lost too much speed, then failed to accelerate when Jimmy bailed, while ETNZ had speed & enough room to flick it round to get the hook.

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11 hours ago, hoom said:

Yes but after the hook is established isn't the luff all the way up to head-to-wind a dialup? I always thought that counts as a dialup.

 

But also the start of the sequence, what got Jimmy in the shit was he predicted ETNZ was going to tack immediately & attempted to close the gauge to block the tack -> forcing a conventional dialup or gybe but Orifice lost too much speed, then failed to accelerate when Jimmy bailed, while ETNZ had speed & enough room to flick it round to get the hook.

I always felt/thought a dial up was when the boats came in from opposite tacks and go head to wind side by side.  As is happening in this video and 1:05.

 

 

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3 hours ago, Boybland said:

I always felt/thought a dial up was when the boats came in from opposite tacks and go head to wind side by side.  As is happening in this video and 1:05.

 

 

Definition in the video (around 1:30) [g-tran] DIAL UP: Stalemate with bow in the wind especially during the five minutes before the start

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On 9/9/2018 at 2:25 PM, Boybland said:

That is not a dial, it's a hook.

It certainly was a wind up... on a cocky little ginger...

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Very interesting story of the new foils. Interesting to note who was part of the creation team tood an the reason he gives to name them.

"We all have separate projects but we like working together. They are my collaborators who decree the success of these projects. I have to mention them all. Is very important. It goes to the cohesion of the study! Here are the names: Romaric Neyhousser, architect; Herve Penfornis, facilities, project management and deck; Morgane Schlumberger, structures and project management; Bobby Kleinschmit, architect and performance; Véronique Soule, fluid dynamics and performance; Nick Holroyd, architect; Leonard Imas and Romain Garo, both fluid dynamics; Louis Pillot, drawings. The group of the Pure en Structure studio in New Zealand is directed by Giovanni Belgrano and counts on Adam Greenwood, Andy Kensington and Martin Bivoit."

Anything but a national team :)

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2 hours ago, Tornado-Cat said:

Very interesting story of the new foils. Interesting to note who was part of the creation team tood an the reason he gives to name them.

"We all have separate projects but we like working together. They are my collaborators who decree the success of these projects. I have to mention them all. Is very important. It goes to the cohesion of the study! Here are the names: Romaric Neyhousser, architect; Herve Penfornis, facilities, project management and deck; Morgane Schlumberger, structures and project management; Bobby Kleinschmit, architect and performance; Véronique Soule, fluid dynamics and performance; Nick Holroyd, architect; Leonard Imas and Romain Garo, both fluid dynamics; Louis Pillot, drawings. The group of the Pure en Structure studio in New Zealand is directed by Giovanni Belgrano and counts on Adam Greenwood, Andy Kensington and Martin Bivoit."

Anything but a national team :)

Umm...Nationality is irrelevant in context to the discussion this quote came from. He isn't naming a "Team" he is naming collaborators he works with to ensure his projects succeed. 

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2 hours ago, Tornado-Cat said:

Very interesting story of the new foils. Interesting to note who was part of the creation team tood an the reason he gives to name them.

"We all have separate projects but we like working together. They are my collaborators who decree the success of these projects. I have to mention them all. Is very important. It goes to the cohesion of the study! Here are the names: Romaric Neyhousser, architect; Herve Penfornis, facilities, project management and deck; Morgane Schlumberger, structures and project management; Bobby Kleinschmit, architect and performance; Véronique Soule, fluid dynamics and performance; Nick Holroyd, architect; Leonard Imas and Romain Garo, both fluid dynamics; Louis Pillot, drawings. The group of the Pure en Structure studio in New Zealand is directed by Giovanni Belgrano and counts on Adam Greenwood, Andy Kensington and Martin Bivoit."

Anything but a national team :)

Nice try at deception, or did you genuinely just misunderstand the article?

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Thanks for that Terry.

OT: I noted this under the video....

Peter Burling – Helmsman, Defender Emirates Team New Zealand
Max Sirena – Team Director and Skipper, Challenger of Record Luna Rossa Challenge
Terry Hutchinson – Executive Director and Skipper, Challenger NYYC American Magic
Ben Ainslie – Team Principal & Skipper, Challenger INEOS TEAM UK

In AC35 ETNZ made the decision to present GA as 'Skipper' over PB, presumably to take some of the pressure off the young and less experienced (PR-wise) helm.*

It looks like this time we can look forward to press conferences and photo-ops featuring 'skippers' who aren't even on the boat!?

Remember those flags featuring GA plus all the other helms? Not sure Casper and Max are the faces they want to feature.....

Lets hope for flexibility in who has to show for what

*though both did some of the 'PR-duty'

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New Zealand have a track record of testing in secret and launching when it suits them....... and not been driven by northern hemisphere calendar, expectations or rumour mongering.

Remember how they developed the SL33 cats, how they developed their own AC50. They are smart and beat the drum to their own tune.

The fact that you do not see testing in Auckland is not indicative that they are not testing.

The foils on the NYYC are what are laughable - no flaps, rudimentary shapes, complete media control, no sailing in anything other than super light airs and obviously therefore no foiling - just not credible. Their deck layout is thought provoking though.

Where will INEOS go over winter? Middle East, Carribean, Auckland or pull the shutters down unless good weather......

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2 hours ago, Boink said:

Where will INEOS go over winter? Middle East, Carribean, Auckland or pull the shutters down unless good weather......

I reckon once you've packed it in a box it doesn't really matter how far you ship it - so I can see them coming all the way to NZ.

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3 hours ago, Boink said:

New Zealand have a track record of testing in secret

I don't recall the secrecy lasting very long. For example there were photo of the SL33 testing here quickly enough,

Local racing carries on 12 months a year in the UK, particularly dinghy racing. I'm not sure Ineos needs to move anywhere.

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7 hours ago, Tropical Madness said:

If you remember the whole story... fouling testing prior to SL33 was done behind a powerboat on a foiling mule, on a random lake...

Exactly. Still maintaining this would be the obvious, more effective and cheaper way forward this time around too

 

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On 9/10/2018 at 10:46 AM, Boybland said:

I always felt/thought a dial up was when the boats came in from opposite tacks and go head to wind side by side.  As is happening in this video and 1:05.

 

 

Wow.  And they used to say that America's Cup racing wasn't exciting!

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17 hours ago, dogwatch said:

For example there were photo of the SL33 testing here quickly enough

My recollection they showed up quite a long time after the AC72 foiling had been revealed.

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17 hours ago, Tropical Madness said:

If you remember the whole story... fouling testing prior to SL33 was done behind a powerboat on a foiling mule, on a random lake...

This is how i recall it. All foil geometry developed on the mule to give the auto regulating ride hide that they were seeking - some inland freshwater lake out in whoop whoop.

Only revealed that this was done after AC72 broke cover.

Caught Oracle flat footed.....

There are lots of remote lakes in both North and South Island to repeat such a programme.

I realise that the UK can be sailed in year round - done it myself - but ripping around at 30 knots with air temps around 0c/32F in Jan/Feb would give a wind chill that might focus the mind in places other than which effect has the latest round of modifications caused.

They are not wanting for budget either......

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17 hours ago, Boink said:

.....

I realise that the UK can be sailed in year round - done it myself - but ripping around at 30 knots with air temps around 0c/32F in Jan/Feb would give a wind chill that might focus the mind in places other than which effect has the latest round of modifications caused.

 

 

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This came up in a conversation and I've been unable to find an answer. Has the battery capacity of the AC75 been announced anywhere, and if so,  how many cycles of the foils (one side down and the other up) does it work out to?

Cheers,

Earl


 

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I would love to know that, too.  And even if supplied batteries, are there legal control system hacks to get more maneuvers out of them?  Would be odd to have to ration tactics for battery constraints.

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1 hour ago, Earl Boebert said:

This came up in a conversation and I've been unable to find an answer. Has the battery capacity of the AC75 been announced anywhere, and if so,  how many cycles of the foils (one side down and the other up) does it work out to?

Cheers,

Earl


 

There was a video recently about the foils, at the 45 second mark they show the pump. If someone is able to identify the motor, then it's power consumption would be know. They state in the video it runs for 15 seconds to recharge the system

 

 

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The Protocol and the Class Rule are obviously written in such a way as to (theoretically) preclude anyone gaining an advantage by 'hacking' the supplied gear

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There seems some latitude in control system design and implemention per Class Rule 22-24.  Is it impossible that certain legal  choices are better than others?  The systems are not, I think, supplied. "Hack" can be a clever workaround or technique (eg a life hack), not always just what one now thinks of as black-hat computer hacking.  

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Based on a (very) superficial study of the video it appears the limiting factor on stored energy is not the battery but the "pre-charge" pressure vessel.

It's a complex bit of gear, and safety-critical. Which raises a few of interesting (to me, at least) questions:

Who does the failure effects analysis and do the challengers get to review it? (Role normally played by national authorities who issue airworthiness certificates for other kinds of flying machines)

Who maintains the device once it is installed in a challenger vessel? The defender? Or are challengers expected to be trained up on on the equipment?

What mechanism exists for redress if a challenger loss (or worse, campaign-ending crash) is attributed to the defender-furnished foil cant system? And who does the accident investigation, should one be needed?

Cheers,

Earl

 

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Excellent questions.

Wonder if there is any challenger review wrt supplied battery specs and quality assurance, too.

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  ^ Worth reading. First note: as in earlier studies, take-off boat speed is estimated at 18.8 kts assumimg weight is evenly distributed over the two foils (not really sure how this can be achieved)

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1 hour ago, etienne.billiet said:

capsize or turtle? it looks like those fast foiling monohulls are stable upside down

But how does it get to upside down with 300kg of buoyancy in the top 1.5m of the sail (per rule 20.24)?

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The article is interesting and certainly tries to support its position with some stated assumptions and calcs.

I come away from reading it with the impression that taken in isolation - it is a credible read. However, the world is not a series of isolated cells with hard boundaries and fixed parameters.

For instance - the author assumes that sail force Oy will only ever contribute a sinking effect - whereas, as soon as the attitude of the rig is horizontal or upwards - this is no longer true, and there are many upsides to maintaining this attitude.

He also offers the scenario that the hydraulic system may not operate in the capsized position - But Why? Being capsized is a very likely outcome - why would you have a system that cannot articulate the foils to the most advantageous position to aid re-righting?

In describing take off he doubts the capacity of single foil action in achieving lift out - and this is certainly true - but if this article is read in conjuction with the knowledge gleaned from the TH articles about how vunerable the boats are at moving off from a standstill - then it is not difficult to comprehend that the boats will not ever attempt lift off with the two foils down in docking mode. More likely that the leeward foil is set for optimum cant angle - whilst the windward foil is canted from docking position (for maximum Righting Moment) to being canted out upwards and out of the water as speed builds - which follows the description by TH about how windward capsize is possible until botspeed has been established.

The teams as a whole will literally be drawing up detailed checklists of foil cant, flap angle and a closely sequenced series of events to ensure that they can repeatably get going each and every time from a standstill. Much like planes have a preflight checklist. Obviously stopping is going to be part of rule #1 - DO NOT EVER STOP

It is interesting also that the assumptions of the article are based around the skiff type hull as defined in the video that launched the class (and as used by the Mule) - whereas Ineos have already cut the nose off their test rig - along with much speculation that Scow like hulls are a distinct possibility - to stop the nose tripping events and give more chance of  hull bounce when things get dynamic.

So I am not writing the article off - just saying that things are already a little further along the evolutionary curve than it suggests.

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2 hours ago, Boink said:

He also offers the scenario that the hydraulic system may not operate in the capsized position - But Why? Being capsized is a very likely outcome - why would you have a system that cannot articulate the foils to the most advantageous position to aid re-righting?

this was the point that i wanted to rebut...but there was sooo much math i was shy . nice unpack thank you

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Regarding Hydraulic system to operate, the point is that you'd better need a remote as not sure there would still be a crew close to the command system...

Regarding take off, it is supposed here to be helped by the 2 foils obviously not in docking position. Being symmetrical, do offer weight balance and maximum lift keeping drag close to docking.  Then, healing angle can be addressed with the windward foil. For sure, this won't be the only scenario and teams may workout strict protocols regarding foil position and maneuver.

For sure, no body have yet the full handbook for those machines however you'd better know about fix parameters of physic calculations...

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Good point about crew stations in a knock down or such. The self righting foil position was inferred in the original animations I believe. I am reminded of burling hanging on in bda, or scenes of crew dropping off the high sides of a knocked down cat. The mono configuration should alleviate some of these awkward positions. We will certainly see pretty soon now, teams will be keen to not have their assets flushed out to sea.

Great work on the physics, thx!

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10 hours ago, etienne.billiet said:

Regarding Hydraulic system to operate, the point is that you'd better need a remote as not sure there would still be a crew close to the command system...

Regarding take off, it is supposed here to be helped by the 2 foils obviously not in docking position. Being symmetrical, do offer weight balance and maximum lift keeping drag close to docking.  Then, healing angle can be addressed with the windward foil. For sure, this won't be the only scenario and teams may workout strict protocols regarding foil position and maneuver.

For sure, no body have yet the full handbook for those machines however you'd better know about fix parameters of physic calculations...

Given it's not a natural orientation a simple inversion switch would be trivial to trigger the foil arms to move into righting mode.

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Since the foil arm hydraulics will be battery powered, will there be an option to charge the batteries from the grinders during the race? If they do too many maneuvers and use up the stored energy?

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1 hour ago, Tom O'Keefe said:

Since the foil arm hydraulics will be battery powered, will there be an option to charge the batteries from the grinders during the race? If they do too many maneuvers and use up the stored energy?

No, my understanding of the rules is that grinding can only be used to control specific surfaces and foils/arms are not one of them...

One would assume there is more than enough power to cover extensive manoeuvring in a race... 

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It could be an interesting tactical twist if their battery capacity did not have a significant surplus. I could see a tacking duel up the final weather leg attempting to run the competition out of power. Will power management become a tactical weapon?

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Does any have a graphical representation of the AC72 vs the AC75?

 

As far as beam and sail height?

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1 hour ago, Tom O'Keefe said:

It could be an interesting tactical twist if their battery capacity did not have a significant surplus. I could see a tacking duel up the final weather leg attempting to run the competition out of power. Will power management become a tactical weapon?

i believe the idea was there would be ample power available for board movement. It would be easy to add another cell to the pack if power needs turn out to be higher than expected.

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1 hour ago, Forourselves said:

A good preview for the future.

 

Muppets on parade.

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1 hour ago, blunderfull said:

SailGP = Muppets on parade.

Fixed it for you.

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I like fail gp, and my predictive text thang predicted it last week when I tried to type sail. Gotta Be true.

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On 4/4/2019 at 1:29 AM, barfy said:

I like fail gp, and my predictive text thang predicted it last week when I tried to type sail. Gotta Be true.

I’m just curious, but how dumb are you that you start with a f instead of an s?  They’re nowhere near each other on a keyboard. If you’re actually honest, your predictive text isn’t very proud of you. Maybe Herby is fucking with your typing. 

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1 hour ago, Monkey said:

I’m just curious, but how dumb are you that you start with a f instead of an s?  They’re nowhere near each other on a keyboard. If you’re actually honest, your predictive text isn’t very proud of you. Maybe Herby is fucking with your typing. 

Huh? They are separated by just one key!

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It's a Swype keyboard.

But thanks for the insult...

Monkey gets me:

Mobley

And

Nobody.

See?

 

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5 hours ago, rh2600 said:

Huh? They are separated by just one key!

That’s not predictive text. That’s bad typing. Cute story though. 

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7 hours ago, Monkey said:

 They’re nowhere near each other on a keyboard.

Mate... you said it... not me... ffs...

If you are this truculent over something so trivial... meatier subjects are going to be hard...

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8 hours ago, Monkey said:

That’s not predictive text. That’s bad typing. Cute story though. 

You are truly a dumb ass fuck wad.

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Ok, so I once more plead laziness, but what do the AC75 grinders power? The foil arms and ride are electric iirc.  So sails? What else? 

Reason I ask is teams are starting to talk about grinders and emphasis on itness trials for continual grinding like with the catamarans. 

 

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These AC 75's will be very hard to sail almost unsailable because they are so unstable. Ineos is basically confirming what Max Sirena said awhile ago.

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On 4/18/2019 at 1:19 PM, NeedAClew said:

Ok, so I once more plead laziness, but what do the AC75 grinders power? The foil arms and ride are electric iirc.  So sails? What else? 

Reason I ask is teams are starting to talk about grinders and emphasis on itness trials for continual grinding like with the catamarans. 

 

I believe the arm lifting hydro is battery powered, leaving foil flaps, rudder rake, and sheets for arm power. And maybe a mechanical computing device :)

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We've been over this before. The Difference Engine was digital, not what you want. The C1 autopilot for the B17 is the place to start.

Cheers,

Earl

 

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On 4/19/2019 at 6:19 AM, NeedAClew said:

Ok, so I once more plead laziness, but what do the AC75 grinders power? The foil arms and ride are electric iirc.  So sails? What else? 

Rule 24.2 defines the permitted electrical actuators in addition to the foil control system (FCS). Everything else is human powered. 

The dual skin sails will likely take a lot more energy to trim than wings, so there will be a lot of grinding.

8 hours ago, barfy said:

I believe the arm lifting hydro is battery powered, leaving foil flaps, rudder rake, and sheets for arm power. And maybe a mechanical computing device :)

Flap and rudder rake actuators are allowed to be electric (Rule 24.2 d, e and f).

 

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To hijack the current thing on this thread and suppose the question 23 pages of chatter ago, I think the following.

In 2013 I was sailing my 28 foot boat around the Waitemata and watching in astonishment as the AC72 cats buzzed about. Then in 2016 the AC50 cat was still wicked fast but way more agile and it was again amazing as fuck. The size difference between the 72 and 50 took some of the stiffness out of my cock but, the maneuverability was something else.

Going ugly early is going to be a proper spectacle. Concern for nose dives and sailors rag dolling into the mast and other hard shit forward is sitting in my guts like a bad curry. Once we see these Jesus lizard beasts can be tickled and dance for their masters, l'll take a turd and give it a name. 

Oh. Barfy. Eat a sack of dicks.

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18 hours ago, RobG said:

 

Rule 24.2 defines the permitted electrical actuators in addition to the foil control system (FCS). Everything else is human powered. 

The dual skin sails will likely take a lot more energy to trim than wings, so there will be a lot of grinding.

Flap and rudder rake actuators are allowed to be electric (Rule 24.2 d, e and f).

 

you are correct sir, i had not perused the V1.1 of the Class Rule, was going from V1.0.

24.2 "Electronic Control Circuits"  (ECC) has changed to 23.2 in V1.1 but was the same text in both versions. The section "Control Systems" has been updated. An inconsistency that has been corrected i guess.

 

"Control Systems" now reads:

21.4  Power that does work on a control surface to adjust its shape, position or orientation can only be supplied by:

(a)  external forces acting on that control surface where, for this Rule only, the combination of the mast, mainsail and any hoisted headsails shall be considered together as a single control surface;

(b)  the crew, via force input devices, only as expressly permitted in Rule 21.2;

(c)  the ECC as permitted by Rules 24.2 (d), 24.2 (e) and 24.2 (f);

(d)  the FCS as permitted by Rule 27;

(e)  no more than 50 J of elastic energy stored within springs or lines (or collections thereof).

"Control Systems" used to read (had to screenshot as V1.0 didn't do copy). This would preclude any actuator control:

rule1.jpg

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On 4/22/2019 at 6:28 AM, barfy said:

"Control Systems" used to read (had to screenshot as V1.0 didn't do copy). This would preclude any actuator control:

rule1.jpg

There was rule 20.2:

20.2 No part of a control system may be capable of using feedback from the yacht state to control a control surface, except:

(e) as permitted within an ECC by Rule 23.

And rule 23 was:

23.3 An ECC can only provide a data output, or provide power to:

(d) electrical actuators that rotate the foil flaps; 

(e) electrical actuators that rotate the rudder about its rake axis;

Which allowed for "feedback from the yacht state" to control flaps and rudder rake (in addition to control by crew operated input devices). That could be very close to electronic ride height control.

The new rules allow electronic sensors to measure ride height, but they can only log data to the ILS. They can't be used to inform the crew though they can be used to set off an alarm, but there are restrictions on how often and how many times they can do that so they can't act like tone a that beeps frequently to indicate too high or too low.

A version of the 1.0 rule that allows copy/paste is at https://www.sailingscuttlebutt.com/wp-content/uploads/2018/03/AC75_Class_Rule.pdf.

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19 hours ago, RobG said:

They can't be used to inform the crew though they can be used to set off an alarm, but there are restrictions on how often and how many times they can do that so they can't act like tone a that beeps frequently to indicate too high or too low.

I see that now, the ILS can talk to the CIS, but still 

26.2The CIS:

(a) shall be incapable of measuring any part of the yacht state;

 

even tho the sensors can feed the ILS, i assume that is just for graphics, these sensors cannot inform the CIS, Crew Information System, or set off alarms about Yacht State.

 

  1. 21.9  Sensors that measure, or are used to estimate the:

    1. (a)  height of the yacht above water;

    2. (b)  vertical velocity of the yacht; or

    3. (c)  vertical acceleration of the yacht

    are permitted only as part of an ILS. Mechanical or other non-electronic sensors measuring these quantities are not permitted.

 

So i'm not getting where you think Yacht state can give crew feedback.

The original question regarding how the control surfaces get their power:

 

  1. 21.4  Power that does work on a control surface to adjust its shape, position or orientation can only be supplied by:

    1. (a)  external forces acting on that control surface where, for this Rule only, the combination of the mast, mainsail and any hoisted headsails shall be considered together as a single control surface;

    2. (b)  the crew, via force input devices, only as expressly permitted in Rule 21.2;

    3. (c)  the ECC as permitted by Rules 24.2 (d), 24.2 (e) and 24.2 (f);

    4. (d)  the FCS as permitted by Rule 27;

    5. (e)  no more than 50 J of elastic energy stored within springs or lines (or collections thereof).

  2. 21.5  Power supplied by the crew to do work on a control surface must be used directly without being stored, except where permitted by Rule 21.4 (e) and by Rule 22.13 within HCCs.

and

 

  1. 23.6  Batteries or regulated power supplies are permitted to be shared between ECCs, the ILS, the CIS, cameras and screens provided that where these systems are required to be isolated, the isolated wiring begins immediately beyond these supplies.

  2. 23.7  ECCs, the ILS, the CIS and electric actuators must be powered by supplies operating at no more than 60 V, except where and if expressly permitted by the FCS specification.

 

So if you want to use an electric actuator to drive control systems you can get power from batteries, but if you want to use a Hydraulic System you have to generate the energy by hand?

Sorry this answer is all over the place, bit short of time to write up a good set of questions for discussion RG.

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I was hinting that v1.0 could have had loopholes allowing electronic ride height, but v1.1 closes them (as far as I can tell).

Rule 25.2 allows the ILS to send alarm signals to the CIS via the Media System (alarm category ID and magnitude), as shown in Fig 23.1.

1646520096_ILStoCISsm.png.0cba5e833125fe72f89c4d86620bee1e.png

Further described in rule 26.1:

26.1 The Media System will make an output available for transmitting data to the CIS, and optionally to the ILS for logging. This output will use a specified protocol and will include:

(a)  the data stream supplied by the ILS, delayed by between 0.5 s and 1.0 s, this delay either being fixed or variable, to be specified;

(b)  non-delayed alarm event messages supplied by the ILS, which:

(i)  once dispatched for a particular category ID, will not be dispatched again for the same category ID for 10 s; and

(ii)  will be limited when racing to a maximum total number of alarms of 20 per race;

 Without those restrictions on alarms, they could be used to help trim the boat.

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Read on https://www.sail-world.com/news/217169/Am-Cup-Barker-says-AC75-different-dynamic

The team has not disclosed speeds except that they are expected to be three or four times windspeed when reaching and slightly less on the upwind leg.

Has this been published or commented previously? We could expect most teams to play down expectations to not give too much away to the competitors which hint toward 4 times windspeed when reaching. With that kind of performance factor, they should easily reach the 50 knots mark... Let's see if summer brings the first sign of a full size boat being splashed.

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Ok, let's get back to some design discussions.  With the test boats, Luna Rosa and UK's T5 have gone with the open cockpit with the helmsman near the mast (center of the boat), while AM Mule has a close cockpit with the helmsman at the back of the boat.  Which design is better and will be used for the full scale boats?  LR has recently released a "concept" of the full size boats and it has the same open cockpit, grinders in the middle and the helmsman near the mast.    Here are some screen shots to show the differences (the UK mule uses a tiller):

 

LR test boat.jpg

LR full size2.jpg

LR full size.jpg

UK T5.jpg

UK T5 2.jpg

AM Mule.jpg

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I can't see the forward helm being a good idea. They have to be able to time manoeuvres based on what the crew is doing, sail state, etc. They can't do that from near the mast.

Closed cockpit is good as it should mean less water in the boat, but makes changing sides much more difficult. But AC sailors already deal with that with the AC72 & 50 cats, in comparison it's easier, but not as easy as an open cockpit.

I don't think the INEOS boat is necessarily anything like their AC75, it was just a convenient hull to use.

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My impression is that manoeuvres are precise team work with the helm focused on the foiling aspect rather than the crew, and the sail looked after by someone else so I don't see the mid helm as a problem. It may have some advantages in seeing more of the horizon?

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The Luna Rossa boat is sex on foils, looking good wins it for me!

Seriously though I love the trimmer relaxing in the back corner with the console controller and helmsman upfront like he's driving some Italian sports car!

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5 hours ago, Boybland said:

The Luna Rossa boat is sex on foils, looking good wins it for me!

Seriously though I love the trimmer relaxing in the back corner with the console controller and helmsman upfront like he's driving some Italian sports car!

True... Wonder how the helmsman butt walks from one station to the other?

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