McGyver

Foils fail.

Recommended Posts

Interesting. PM sounds to be sure about his source, and generally doesn't BS about such things. I think the foils are being built at Persico in Italy for all. They know what they are doing with foils and have built enough. Under engineered or loads higher than originally expected? 

Share this post


Link to post
Share on other sites

The loads would presumably be predicated loads at this point. So a design or engineering problem.

Share this post


Link to post
Share on other sites
27 minutes ago, dogwatch said:

The loads would presumably be predicated loads at this point. So a design or engineering problem.

Or the testing may have been tougher than the designers imagined.  The video of the tests demonstrated severe dynamic loading and they may have used more ballast than is intended for the actual boats.

Share this post


Link to post
Share on other sites

Wait, I thought that ETNZ that the most brilliant engineers and most sophisticated simulation software?  You mean they made an error in the design and it is not working, impossible!  Maybe they will have to scale down the size of the boats, obviously the UK and US have been able to do it on smaller boats.  I can see it now, the AC35 lizard boats....

Share this post


Link to post
Share on other sites

The whole canting mechanism (arms and actuator) pose some very challenging engineering problems, especially when considered from a life cycle perspective.

Consider the point in the evolution from down to up where the outboard end of the arm has just cleared the water but the lower half (or so) of the foil is still immersed. It looks like the arm will simultaneously be subject to longitudinal bending (weight of ballasted foil), lateral bending (drag of foil in the water) and torsion (drag of foil leveraged to point of attachment to arm). That's a lot of stuff to consider, especially when the possibility of vibration is taken into account.

The actuator combines hydraulics, analog electricity and digital systems. It has been my experience that mixed-technology systems such as this can be very difficult and expensive to test, especially if they are constructed without extensive (and expensive, and time-consuming) efforts during the concept formulation and specification phases. As the saying goes, a system that is produced without a specification can never be wrong, only surprising. If something lets go when you're flying along at 50+ kt, surprises can be nasty.

I may be missing something, but in all the discussions about rules and protocols I cannot find any evidence that there is an independent group that produces the moral equivalent of an airworthiness certificate for these flying machines. Self-certification was practiced in the early days of aviation, with decidedly mixed results.

The life cycle issue is that of continuing maintenance and  re-inspection. Again, that may be in there somewhere but I haven't found it.

Cheers,

Earl

 

  • Like 7

Share this post


Link to post
Share on other sites
13 hours ago, Xlot said:

Not foils, foil arms - see the LR thread

Agreed. Foils are pretty much known territory. Consider the immense shock loading on the foils of a boat like Hugo Boss in the Route du Rhum.

Foil arms are a different kettle of fish. As Earl Boebert has noted above, all kinds of new anddifferent load problems to take into account.

 

Share this post


Link to post
Share on other sites

Earl hits the nail on the head. It’s laughable how people in sailing think they know more than people in aerospace, and before anyone says “yeah but airbus” or whoever, you are on glue if you think there’s been anywhere near enough money budgeted for real testing of all these systems even if an aerospace company is involved. 

  • Like 4

Share this post


Link to post
Share on other sites
1 hour ago, sunseeker said:

It’s laughable how people in sailing think they know more than people in aerospace, and before anyone says “yeah but airbus” or whoever, you are on glue if you think there’s been anywhere near enough money budgeted for real testing of all these systems even if an aerospace company is involved. 

QI composites have been bought in to load test the foil arms, under observation from all four teams. Not sure who is picking up the tab - probably the Defender - .You don't think there is merit in this approach? What sort of money should they be spending to test the foil arms?

Share this post


Link to post
Share on other sites
7 hours ago, dg_sailingfan said:

Why didn't they stay put with the existent foiling technology instead of these crappy, bad looking arms?

You've nailed your colours to the mast with this comment A4E. Wishing the whole event to fail are we?

Share this post


Link to post
Share on other sites
1 hour ago, sunseeker said:

Earl hits the nail on the head. It’s laughable how people in sailing think they know more than people in aerospace, and before anyone says “yeah but airbus” or whoever, you are on glue if you think there’s been anywhere near enough money budgeted for real testing of all these systems even if an aerospace company is involved. 

Bingo!!!!  Even NASA had to physically test their concepts.

  • Like 1

Share this post


Link to post
Share on other sites
21 minutes ago, Horn Rock said:

QI composites have been bought in to load test the foil arms, under observation from all four teams. Not sure who is picking up the tab - probably the Defender - .You don't think there is merit in this approach? What sort of money should they be spending to test the foil arms?

Not sure that Stefano and co have the expertise to determine the load requirements or test methods for this. Checking quality control yes, but load testing? Persico have the test rig and expertise in house for that. Determining the testing process is the issue I would think.

  • Like 1

Share this post


Link to post
Share on other sites
25 minutes ago, Horn Rock said:

QI composites have been bought in to load test the foil arms, under observation from all four teams. Not sure who is picking up the tab - probably the Defender - .You don't think there is merit in this approach? What sort of money should they be spending to test the foil arms?

Have you ever seen what wing testing is really like at a place like Boeing? That’s the level of testing that should be taking place. Let us know when QI Composites does destructive wing testing for large aircraft.

 

 

Share this post


Link to post
Share on other sites
5 minutes ago, Chimp too said:

Determining the testing process is the issue I would think.

All parties involved would  be acutely aware that they have to get these foil arms right - there's no leeway here. Having any of them fail in the ACWS would be embarrassing. Failing in the main event would be catastrophic. I've confidence that Dalts is aware of the stakes involved and do what's required, even if that means spending more cash.

Share this post


Link to post
Share on other sites
3 minutes ago, sunseeker said:

Have you ever seen what wing testing is really like at a place like Boeing?

Obviously I haven't. Is large scale aircraft wing testing totally comparable to foil arms for a sail boat?

Share this post


Link to post
Share on other sites
1 minute ago, Horn Rock said:

All parties involved would  be acutely aware that they have to get these foil arms right - there's no leeway here. Having any of them fail in the ACWS would be embarrassing. Failing in the main event would be catastrophic. I've confidence that Dalts is aware of the stakes involved and do what's required, even if that means spending more cash.

Dalton is by his own admission a cheapskate. He wouldn’t spend the money that is really necessary even if he had it. He’s always crying poor, so I don’t see him spending what us really required. $50 million might be a good start, to say nothing of the time required to do everything properly. We aren’t taking months, it’s years.

Share this post


Link to post
Share on other sites
2 minutes ago, Horn Rock said:

Obviously I haven't. Is large scale aircraft wing testing totally comparable to foil arms for a sail boat?

Yes. What’s the difference? The foil and the wing of an airplane are exactly the same concept, and the foil on these boats might even be more complex because it’s going through both air and water, the dynamic loading is massive.

  • Like 2

Share this post


Link to post
Share on other sites
7 minutes ago, sunseeker said:

The foil and the wing of an airplane are exactly the same concept, and the foil on these boats might even be more complex because it’s going through both air and water, the dynamic loading is massive.

I'm not disputing what you're saying, we'll just have to see how this plays out. The potential for disaster is definitely there though. On a positive note, the Mule concept whilst scaled down, has looked to be pretty good, and that's with minimal development time. I'm not convinced yet that they can't solve the structural issues, but of course it remains to be seen. 

Share this post


Link to post
Share on other sites
1 hour ago, sunseeker said:

Yes. What’s the difference? The foil and the wing of an airplane are exactly the same concept, and the foil on these boats might even be more complex because it’s going through both air and water, the dynamic loading is massive.

There have been very few reports of airplanes hitting dolphins or sea turtles while underway . 

Share this post


Link to post
Share on other sites
2 hours ago, sunseeker said:

Dalton is by his own admission a cheapskate. He wouldn’t spend the money that is really necessary even if he had it. He’s always crying poor, so I don’t see him spending what us really required. $50 million might be a good start, to say nothing of the time required to do everything properly. We aren’t taking months, it’s years.

The costs of all matters connected to the foil control system will be spread among the users. It's not Dalton's problem.

Share this post


Link to post
Share on other sites
3 hours ago, sunseeker said:

Yes. What’s the difference? The foil and the wing of an airplane are exactly the same concept, and the foil on these boats might even be more complex because it’s going through both air and water, the dynamic loading is massive.

You are confusing foils with foil arms...

Share this post


Link to post
Share on other sites
1 hour ago, Chimp too said:

The loads get transferred through to the arm

I think Sunseekers suggestion that testing a aeroplane wing and testing a foil arm is the same thing is not correct...

I think he missed hornrock's mention of the arm... you could argue that load testing a wing is similar, bit I can't think of many planes that have their wing on an articulated arm - the part that is evidently proving challenging...

Share this post


Link to post
Share on other sites

Agree. The torsional loads as the arm moves between fluids at speed must be huge compared to a wing on a plane. It was all theoretical when the arms were first engineered. Maybe with info now coming from real world tests they are finding that the loads require more extreme testing. Better to find out now I suppose.

Share this post


Link to post
Share on other sites
4 hours ago, rh2600 said:

You are confusing foils with foil arms...

You are confusing boat parts with wisdom and experience.

Share this post


Link to post
Share on other sites
2 hours ago, rh2600 said:

I think Sunseekers suggestion that testing a aeroplane wing and testing a foil arm is the same thing is not correct...

I think he missed hornrock's mention of the arm... you could argue that load testing a wing is similar, bit I can't think of many planes that have their wing on an articulated arm - the part that is evidently proving challenging...

Thank you for making my point. It is exactly that these foils articulate that is the massive engineering challenge. It’s not that unlike a wing on an airplane because a great deal of flex is built into the wing and the root at the fuselage has to be engineered for that. 

As Earl pointed out, there’s multiple systems involved, to say nothing of the materials that need to be analyzed.

i have to laugh about this boat. It’s a poor mans way to speed. They have this dual skin sail as a cost saving move so they don’t have to have wings and all those associated expenses. No doubt that the dual sided sail will improve dual sided sail technology, but it’s not a wing.

putting a dual side sail on this boat is somewhat like saying “we are going to come up with better bias ply tires for Ferrari so we save the cost of a Perrelli P-Zero”.

the concept is kiwi cheap.

Share this post


Link to post
Share on other sites
7 hours ago, sunseeker said:

Have you ever seen what wing testing is really like at a place like Boeing? That’s the level of testing that should be taking place. Let us know when QI Composites does destructive wing testing for large aircraft.

 

 

Seriously doubt Boeing does X-ray tomography tests - size is obviously an issue. You’re right though about their wing tests being spectacular - on the 787 the amount of flex was unreal. Thei didn’t seem to use anything more advanced than the traditional sandbags though, and IIRC on the 787 wing failure was below the design value too

Share this post


Link to post
Share on other sites
15 minutes ago, Xlot said:

Seriously doubt Boeing does X-ray tomography tests - size is obviously an issue. You’re right though about their wing tests being spectacular - on the 787 the amount of flex was unreal. Thei didn’t seem to use anything more advanced than the traditional sandbags though, and IIRC on the 787 wing failure was below the design value too

The destructive testing Boeing does on a wing is way more advanced than sandbags.

they can X-ray these arms and  foils all they want, that isn’t going to really get them to the engineering they need.

Ive heard several people say “but the mule works, so that’s good enough”. Ok, now scale it up, sail it in significantly more breeze and sea state than we’ve seen so far.

if these engineering costs are spread among all the teams, these late comers would be well advised to be no shows. They have agreed to become an open checkbook R&D funding source for Dalton’s wet dream.

Share this post


Link to post
Share on other sites
8 hours ago, Chimp too said:

Not sure that Stefano and co have the expertise to determine the load requirements or test methods for this. Checking quality control yes, but load testing? Persico have the test rig and expertise in house for that. Determining the testing process is the issue I would think.

Stefano implies that the first batch of arms will be saturated with sensors to determine real life stresses, so that the second batch may incorporate lessons learned

Once again, load assumptions are not part of QI’s domain, just as carbon layups are not Persico’s responsibility: this was once LR’s structural designers’ duty, and should now have been transfered to “kiwi” Giovanni Belgrano - and you can bet engineers from the other teams will now be fully informed about every design step

About load assumptions, the design of recent ultra-slender keels for conventional yachts has brought to the fore the importance of torque loads: this is not intuitively obvious, but in fact is quite often the determining stress condition

Share this post


Link to post
Share on other sites

The foil arm assembly--arms, hinge, connectors, hydraulics,  etc.--have to work under dynamic load time after time after time.  Testing would be complex. Simulation involves deciding what to simulate...

An inexact analogy in aircraft might be the tiltrotor Osprey-V22 that thing has been a contention banquet of issues for decades  https://en.m.wikipedia.org/wiki/Accidents_and_incidents_involving_the_V-22_Osprey

  • Like 1

Share this post


Link to post
Share on other sites

Since the foils are ballasted weight is not an issue.  When the boats are foiling the arms are not producing any drag.  What's the problem then in making the arms a bit thicker and much stronger?

Share this post


Link to post
Share on other sites
7 minutes ago, McGyver said:

Since the foils are ballasted weight is not an issue.  When the boats are foiling the arms are not producing any drag.  What's the problem then in making the arms a bit thicker and much stronger?

How much thicker? Heavier? What shape? What connections?  What materials?  What load range? Torque? Stress/strain?  No problem. Easy peasy. Quick and dirty good enuf. (sorry for sarcasm)

Share this post


Link to post
Share on other sites

https://www.sail-world.com/news/212692/Italian-Challenger-running-AC75-rig-on-test-boat

"They also report on the foil arm development by Luna Rossa:

The technology under scrutiny is that of the foil arms, which have been routinely cracked by Persico Marine and which would be giving further concern to the designers. The loads are very high and, since it is an equal design component for all the teams (the foil will be instead of free design), before you can trust them you will still need several tests. The next one is scheduled in January, again from Persico.

Sail-World understands that while the arms are built at Persico, they are designed now by Auckland based composite engineers Pure Design. The Foil Cant System is a fully operational system in Auckland. The test failure of an arm is not a significant setback and will not affect any launch or sailing programs"

Share this post


Link to post
Share on other sites

^oh, goody. So come April Fool's Day the first Cup boats will be in the water?

Share this post


Link to post
Share on other sites
7 hours ago, sunseeker said:

the concept is kiwi cheap.

You surely mean to say kiwi winning

Share this post


Link to post
Share on other sites
20 minutes ago, NeedAClew said:

^oh, goody. So come April Fool's Day the first Cup boats will be in the water?

So come April Fool's Day the first Cup boats will can be in the water. Doesn't mean they "Will" be. All teams will have their own launch schedules, but the date they "Can" launch is April 1st.

Share this post


Link to post
Share on other sites
3 hours ago, McGyver said:

Since the foils are ballasted weight is not an issue.  When the boats are foiling the arms are not producing any drag.  What's the problem then in making the arms a bit thicker and much stronger?

They are also a one design components so if there are any disadvantages they are applied equally to all teams.

Share this post


Link to post
Share on other sites
3 hours ago, mfluder said:

So come April Fool's Day the first Cup boats will can be in the water. Doesn't mean they "Will" be. All teams will have their own launch schedules, but the date they "Can" launch is April 1st.

Uh, assuming they have all their A-OK supplied parts. 

Share this post


Link to post
Share on other sites
1 hour ago, NeedAClew said:

Uh, assuming they have all their A-OK supplied parts. 

Which according to Gladwell sounds like its a non-issue 

Share this post


Link to post
Share on other sites
23 hours ago, sunseeker said:

Have you ever seen what wing testing is really like at a place like Boeing? That’s the level of testing that should be taking place. Let us know when QI Composites does destructive wing testing for large aircraft.

 

 

Ive seen QI do destructive testing with my own eyes on multiple boards and yacht parts. why would they need to do it for large aircraft, they have a huge amount of expertise in carbon construction testing and fault finding. 

Share this post


Link to post
Share on other sites
25 minutes ago, agk470 said:

Ive seen QI do destructive testing with my own eyes on multiple boards and yacht parts. why would they need to do it for large aircraft, they have a huge amount of expertise in carbon construction testing and fault finding. 

Funny that, as QI specialise in non-destructive testing.

Share this post


Link to post
Share on other sites

impossible, fake news.

ETNZ wouldn't even be doing physical tests, their simulations are so accurate that they wouldn't need too!

last cup, they brought out a finished boat straight out of simulation.

all the other rich trash teams spend money on surrogates and physical testing. LOOK WHERE IT GOT THEM LAST CUP HAHAHAHA

heads up their asses i tell you!

>sarcasm

maybe their simulations aren't so good after all. food for thought

also, maybe everything we are doing is in a simulation.......

Share this post


Link to post
Share on other sites
58 minutes ago, inebriated said:

impossible, fake news.

ETNZ wouldn't even be doing physical tests, their simulations are so accurate that they wouldn't need too!

last cup, they brought out a finished boat straight out of simulation.

all the other rich trash teams spend money on surrogates and physical testing. LOOK WHERE IT GOT THEM LAST CUP HAHAHAHA

heads up their asses i tell you!

>sarcasm

maybe their simulations aren't so good after all. food for thought

also, maybe everything we are doing is in a simulation.......

Or maybe you just don't know what you're talking about...again.

Share this post


Link to post
Share on other sites
9 hours ago, mfluder said:

https://www.sail-world.com/news/212692/Italian-Challenger-running-AC75-rig-on-test-boat

"They also report on the foil arm development by Luna Rossa:

The technology under scrutiny is that of the foil arms, which have been routinely cracked by Persico Marine and which would be giving further concern to the designers. The loads are very high and, since it is an equal design component for all the teams (the foil will be instead of free design), before you can trust them you will still need several tests. The next one is scheduled in January, again from Persico.

Sail-World understands that while the arms are built at Persico, they are designed now by Auckland based composite engineers Pure Design. The Foil Cant System is a fully operational system in Auckland. The test failure of an arm is not a significant setback and will not affect any launch or sailing programs"


So, the foil arms are now being designed by the incomparable Giovanni Belgrano and his team at Pure Design here in Auckland,  built by Persico Marine Composites in Nembro, Italy and tested by QI Composites in Pivarone, Italy, led by Stefano Beltrando using ultrasound testing as well as X-ray tomography. Plus it sounds as if the Defender and all accepted Challengers get the opportunity to audit the process.

Between the three principals there's a lengthy and impressive history of marine successes. Reason to be confident they'll get it right.

Share this post


Link to post
Share on other sites

Well that's nice and they can all  bask in your approval  but if these failures have indeed set everyone's programme back 3 months and consequently limited ACWS 2019 to a single event, they didn't get it all that right first time.

Share this post


Link to post
Share on other sites
4 hours ago, Chimp too said:

Funny that, as QI specialise in non-destructive testing.

Yes, but that doesn't preclude them also doing destructive mechanical testing. 

Test of Mechanical Characterisation

Through the close collaboration of specialised laboratories, we carry out mechanical characterisation tests. These tests are destructive, carried out on specially produced specimens and aim to define the characteristics of mechanical resistance and the behaviour of the material subjected to almost static loads. The applicable loads can be: traction, compression, flexion (3 or 4 points), cutting. The investigatable materials and structures can be monolithic composites or sandwiches and metals
International certification bodies have created regulations specifically designed to obtain precise characteristics from each type of test.

That infers that through destructive testing, they should be able to recommend changes to make the structure pass the tests. So it may be that they have been failing earlier than expected, so upgrades get them through one phase of testing, but then they fail at the next.

1.5 tonnes at the end of a 3.3m arm, dropping into the water at 50kn must place enormous stress on the arm, with huge torque as one side immerses first. Also crashing off foils while one is raised, the boat will decelerate quickly, but the raise arm will not want to.

Share this post


Link to post
Share on other sites
35 minutes ago, mfluder said:

Or maybe you just don't know what you're talking about...again.

ah yes,

all those who  don't suck ETNZ's dick for a simulation that clearly is not great are dumbasses

right on champ

  • Like 1

Share this post


Link to post
Share on other sites

RobG, 

my comment was more about AKG seeing QI do destructive on multiple occasions. I have spent many days with Stefano and his guys, and never seen them doing destructive testing. 

Persico, Pure and QI will I am sure do a first class job, but only with the information provided to them. If the simulation undercooked the loads, or missed a specific load case, then that won’t get engineered or built for.

Share this post


Link to post
Share on other sites

People seem to assume that the foil system has been designed and built by ETNZ.  

They may have designed the concept but with it being a one design system supplied to each boat I expect ETNZ and Prada would get subcontractors to do the work as this would contain the costs so that they could be shared equally and fairly.

Share this post


Link to post
Share on other sites
1 hour ago, dogwatch said:

Well that's nice and they can all  bask in your approval  but if these failures have indeed set everyone's programme back 3 months and consequently limited ACWS 2019 to a single event, they didn't get it all that right first time.

I dunno!  I can't get very excited by that "respected yachting commentator" Pete Montgomery frothing on Radio Sport about "failing foils" setting back the program three months and then being quoted by the equally respected NZ Herald in a story lacking a byline. In case you didn't notice, the problem is arms, not foils, but that was of no consequence to Pistol Pete. 

Sure there will be consequences. They can't sort out  fitting and engineering the arms into the boats until they know what they look like or the loads they'll impose on the hulls. Still three months seems like a bloody long time.

 

Share this post


Link to post
Share on other sites
3 hours ago, KiwiJoker said:


So, the foil arms are now being designed by the incomparable Giovanni Belgrano and his team at Pure Design here in Auckland,  built by Persico Marine Composites in Nembro, Italy and tested by QI Composites in Pivarone, Italy, led by Stefano Beltrando using ultrasound testing as well as X-ray tomography. Plus it sounds as if the Defender and all accepted Challengers get the opportunity to audit the process.

Between the three principals there's a lengthy and impressive history of marine successes. Reason to be confident they'll get it right.

 

So, all’s well - except Persico are still livid their reputation is suffering unfairly,  since it’s “their” initial arm  that is considered to have underperformed, while in reality it’s the “LR designed” one.

They must be cursing the day they accepted to get involved in this - long association with LR - while their strong point really is large, out-of-autoclave stuff. 

In fact, were one to freely select a manufacturer for comparatively small, autoclaved experimental items, the obvious choice would be not Persico but Re Fraschini - just ask the French

 

Share this post


Link to post
Share on other sites
7 minutes ago, Xlot said:

 

So, all’s well - except Persico are still livid their reputation is suffering unfairly,  since it’s “their” initial arm  that is considered to have underperformed, while in reality it’s the “LR designed” one.

They must be cursing the day they accepted to get involved in this - long association with LR - while their strong point really is large, out-of-autoclave stuff. 

In fact, were one to freely select a manufacturer for comparatively small, autoclaved experimental items, the obvious choice would be not Persico but Re Fraschini - just ask the French

 

Re Fraschini don’t have as much foil experience as Persico. But they do know how to charge! Don’t know if you have visited either recently, but I wouldn’t say Persico are new to autoclaves in anyway.

Share this post


Link to post
Share on other sites
48 minutes ago, Xlot said:

 

So, all’s well - except Persico are still livid their reputation is suffering unfairly,  since it’s “their” initial arm  that is considered to have underperformed, while in reality it’s the “LR designed” one.

They must be cursing the day they accepted to get involved in this - long association with LR - while their strong point really is large, out-of-autoclave stuff. 

In fact, were one to freely select a manufacturer for comparatively small, autoclaved experimental items, the obvious choice would be not Persico but Re Fraschini - just ask the French

 

Ultimately, this problem falls to one guy, Grant Dalton. He’s the guy that makes the final decision. He’s the guy who approved designing this camel of a boat, and then said his guys were so good they don’t even need to do a proof of concept.

Everyone else in this equation is going along for the ride either because of ego or a desire to get paid.

Anyone who suffers here is getting what they deserve.

  • Like 2

Share this post


Link to post
Share on other sites
2 hours ago, KiwiJoker said:

I dunno!  I can't get very excited by that "respected yachting commentator" Pete Montgomery frothing on Radio Sport about "failing foils" setting back the program three months and then being quoted by the equally respected NZ Herald in a story lacking a byline. In case you didn't notice, the problem is arms, not foils, but that was of no consequence to Pistol Pete. 

Fair enough, perhaps I've taken this story more at face value than it deserves. We shall see.

Share this post


Link to post
Share on other sites
53 minutes ago, sunseeker said:

Ultimately, this problem falls to one guy, Grant Dalton. He’s the guy that makes the final decision. He’s the guy who approved designing this camel of a boat, and then said his guys were so good they don’t even need to do a proof of concept.

Everyone else in this equation is going along for the ride either because of ego or a desire to get paid.

Anyone who suffers here is getting what they deserve.

Some pretty harsh criticism there. I disagree though, and feel the AC75 concept is a ballsy, bold move from ETNZ. Is it risk free? Probably not, but I haven't seen any issues that are ultimately not surmountable. The recent flurry of interest in challenging suggests others don't either.

Share this post


Link to post
Share on other sites
46 minutes ago, Horn Rock said:

Some pretty harsh criticism there. I disagree though, and feel the AC75 concept is a ballsy, bold move from ETNZ. Is it risk free? Probably not, but I haven't seen any issues that are ultimately not surmountable. The recent flurry of interest in challenging suggests others don't either.

There is already damage, significant damage, to the teams that rely on sponsorship, which seems like everyone but Ainslie. Every team has been pitching ACWS events as part of their sponsorship proposal. Now, they have to go back and say “uh well, I guess we aren’t going to have as many ACWS events as we said there would be”. 

If you were an employee with their job on the line if you committed company money and time/resources to a team that in the middle of the sales process started paring down their deliverables, and didn’t ask the question “what else might go wrong?”, you’d not have a job for very long.

And people wonder why it’s so hard to get, and keep, sponsors for this regatta.

  • Like 1

Share this post


Link to post
Share on other sites
6 minutes ago, sunseeker said:

There is already damage, significant damage, to the teams that rely on sponsorship, which seems like everyone but Ainslie. Every team has been pitching ACWS events as part of their sponsorship proposal. Now, they have to go back and say “uh well, I guess we aren’t going to have as many ACWS events as we said there would be”. 

If you were an employee with their job on the line if you committed company money and time/resources to a team that in the middle of the sales process started paring down their deliverables, and didn’t ask the question “what else might go wrong?”, you’d not have a job for very long.

And people wonder why it’s so hard to get, and keep, sponsors for this regatta.

Bold: You have seen the teams' contracts with their sponsors? Wow, I'm impressed. Care to share even more detail?

Share this post


Link to post
Share on other sites
17 minutes ago, sunseeker said:

I guess we aren’t going to have as many ACWS events as we said there would be”. 

That hasn't been confirmed by the Defender or the CoR afaik. You might be jumping the gun here? The possibility exits that there may be more ACWS events if some of the new challenges are accepted.

Share this post


Link to post
Share on other sites
42 minutes ago, Rennmaus said:

Bold: You have seen the teams' contracts with their sponsors? Wow, I'm impressed. Care to share even more detail?

Oh fuck you. You know god damn well that everyone tries to make a county fair out of the America’s Cup and whore it out to whoever the can, starting with and especially Dalton.

Share this post


Link to post
Share on other sites
32 minutes ago, Horn Rock said:

That hasn't been confirmed by the Defender or the CoR afaik. You might be jumping the gun here? The possibility exits that there may be more ACWS events if some of the new challenges are accepted.

Yup, that’s all going to happen just like a bag of $100 bills is going to fall out of the sky and into your lap.

Share this post


Link to post
Share on other sites
1 minute ago, sunseeker said:

Oh fuck you. You know god damn well that everyone tries to make a county fair out of the America’s Cup and whore it out to whoever the can, starting with and especially Dalton.

So you have no idea and just make things up. Fine. Shrug.

Share this post


Link to post
Share on other sites
4 hours ago, Chimp too said:

Re Fraschini don’t have as much foil experience as Persico. But they do know how to charge! Don’t know if you have visited either recently, but I wouldn’t say Persico are new to autoclaves in anyway.

Not saying Persico don’t have autoclaves, but IMHO Re Fraschini have more experience in the practicalities of translating a structural design into something that  can actually be laid up, i.e. complying with limited space and access for intricate configurations (think carrying loads around the hinge).  I’ve seen them being very cooperative and coming out with solutions I wouldn’t have thought of

Share this post


Link to post
Share on other sites
23 hours ago, NeedAClew said:

How much thicker? Heavier? What shape? What connections?  What materials?  What load range? Torque? Stress/strain?  No problem. Easy peasy. Quick and dirty good enuf. (sorry for sarcasm)

I think your sarcasm is misplaced.  If weight is not an issue and (as Boybland astutely mentioned) shape is not either, since arms are a one-design item, making them stronger is not a big deal.

Connections?  That's a different animal.  Designing something that "turns" is far more complicated than something that is fixed.

Share this post


Link to post
Share on other sites

Making them the right kind of stronger is a bit of a deal, imho.  We will see what they do end up with. I doubt a "thick as a post" arm made up randomly. Others may think otherwise. 

Share this post


Link to post
Share on other sites
4 hours ago, Rennmaus said:

So you have no idea and just make things up. Fine. Shrug.

It's a fucking internet forum with a bunch of idiots on it. What part of that do you not get?

Share this post


Link to post
Share on other sites
9 hours ago, Terry Hollis said:

People seem to assume that the foil system has been designed and built by ETNZ.  

They may have designed the concept but with it being a one design system supplied to each boat I expect ETNZ and Prada would get subcontractors to do the work as this would contain the costs so that they could be shared equally and fairly.

Nice. You Kiwi's are masters of having it both was. If it's successful it is Kiwi innovation and if it fails it's someone else's fuckup. Seems as though you just made up that second sentence and as Rennmaus just informed us you are not allowed to do that.

  • Like 2

Share this post


Link to post
Share on other sites
9 minutes ago, pusslicker said:

It's a fucking internet forum with a bunch of idiots on it. What part of that do you not get?

What part of "shrug" do you not get?

  • Like 3

Share this post


Link to post
Share on other sites
1 hour ago, NeedAClew said:

Making them the right kind of stronger is a bit of a deal, imho.  We will see what they do end up with. I doubt a "thick as a post" arm made up randomly. Others may think otherwise. 

I think the point was simply that - since the arms are one design, and not the critical primary lifting surface - they have some wriggle room in the design space with regards to external dimensions of the arms, which is huge with regards to structural design of slender objects. You would have no similar option in the design of the actual wing, since any deviation from the optimum design shape would put that team at a disadvantage.

Share this post


Link to post
Share on other sites
3 minutes ago, pusslicker said:

Nice. You Kiwi's are masters of having it both was. If it's successful it is Kiwi innovation and if it fails it's someone else's fuckup. Seems as though you just made up that second sentence and as Rennmaus just informed us you are not allowed to do that.

Sorry that you're so weak. Your arrogant language implied you had bigger balls than that, but apparently you let a random internet poster dictate you what you can do on a weird forum. 

  • Like 3

Share this post


Link to post
Share on other sites
6 hours ago, Rennmaus said:

Bold: You have seen the teams' contracts with their sponsors? Wow, I'm impressed. Care to share even more detail?

Ever seen a sales pitch to a sponsor not including all the events ?

Share this post


Link to post
Share on other sites
1 hour ago, surfsailor said:

I think the point was simply that - since the arms are one design, and not the critical primary lifting surface - they have some wriggle room in the design space with regards to external dimensions of the arms, which is huge with regards to structural design of slender objects. Especially torsional stiffness, which varies with the fourth power of linear dimensions

You would have no similar option in the design of the actual wing, since any deviation from the optimum design shape would put that team at a disadvantage.

 

Share this post


Link to post
Share on other sites
21 minutes ago, Tornado-Cat said:

Ever seen a sales pitch to a sponsor not including all the events ?

Ever seen an AC sales pitch at all?

O.k., forget it, this thread's about foil (arms)...

  • Like 1

Share this post


Link to post
Share on other sites
21 minutes ago, Xlot said:

Especially torsional stiffness, which varies with the fourth power of linear dimensions

While there are definitely significant torsional loads related to hydro drag and impact, I think the bending moment(s) will be the deciding factor at failure. It's a very complex thing to model - even the lifting wing itself introduces a moment since the flaps are independent, and (via anhedral) the two 'legs' of the wing can be set up to isolate leeway loads from lifting loads.

There is an empirical element in the design of composite structures of this complexity - it seems inevitable to me that there would be some failures during the development process, but that's not an indictment of either the concept or the program. 

Share this post


Link to post
Share on other sites

Forgive the ignorant question, but itvhas been a while since I reread things. When (if) those suckers are not foiling, the foil arm assembly is in the water and is the RM keel substitute, right? So it might be in the water during maneuvers, with those kinds of forces.   

Share this post


Link to post
Share on other sites
53 minutes ago, NeedAClew said:

Forgive the ignorant question, but itvhas been a while since I reread things. When (if) those suckers are not foiling, the foil arm assembly is in the water and is the RM keel substitute, right? So it might be in the water during maneuvers, with those kinds of forces.   

Yup, one or both of them can be in the water before getting up to foiling speed...

one will be in as it tries to climb to foil, two can be in when the boat is running in 'displacement mode'...

Share this post


Link to post
Share on other sites

They have weight then...plus the shear and torques from water and accelerations?  So a lot to anticipate, sim, test?

Share this post


Link to post
Share on other sites
9 hours ago, Rennmaus said:

Sorry that you're so weak. Your arrogant language implied you had bigger balls than that, but apparently you let a random internet poster dictate you what you can do on a weird forum. 

Why would I let you dictate what I say on an internet forum full of half wits and retards? You've got to give me more to work with if we are going to keep this going. Your rebuttal makes no sense. 

Share this post


Link to post
Share on other sites
10 hours ago, Rennmaus said:

Sorry that you're so weak. Your arrogant language implied you had bigger balls than that, but apparently you let a random internet poster dictate you what you can do on a weird forum. 

Although it is cute that you are thinking of my balls. 

Share this post


Link to post
Share on other sites
On 12/2/2018 at 5:49 PM, Chimp too said:

Funny that, as QI specialise in non-destructive testing.

There appears to be more to them than you know :) may have been that you havnt asked them to do any. 

Share this post


Link to post
Share on other sites
19 hours ago, sunseeker said:

There is already damage, significant damage, to the teams that rely on sponsorship, which seems like everyone but Ainslie. Every team has been pitching ACWS events as part of their sponsorship proposal. Now, they have to go back and say “uh well, I guess we aren’t going to have as many ACWS events as we said there would be”. 

If you were an employee with their job on the line if you committed company money and time/resources to a team that in the middle of the sales process started paring down their deliverables, and didn’t ask the question “what else might go wrong?”, you’d not have a job for very long.

And people wonder why it’s so hard to get, and keep, sponsors for this regatta.

Whilst you are right, sponsorship is hard enough to get at the best of times let alone retain with huge unknowns. No sponsor is going to get involved without a huge amount of due diligence and at some point there are going to expect big changes along the way.

You have to bear in mind that the AC is a highly complicated beast of an event.... This cup has had huge questions already with a pretty high tariff design on the table from the beginning and now we see a good event coming together.

Dalton did a great job of winning to cup with NZ, he managed a team with limited funds, kept the right guys involved to get the job done and now they are defending the trophy they set out to win. Albeit with some help from others along the way which have no doubt effected the next cup cycle....

In no way will the AC ever be plain sailing, but the good news is.... we are always going to have plenty to talk about!

Share this post


Link to post
Share on other sites
8 hours ago, NeedAClew said:

Forgive the ignorant question, but itvhas been a while since I reread things. When (if) those suckers are not foiling, the foil arm assembly is in the water and is the RM keel substitute, right? So it might be in the water during maneuvers, with those kinds of forces.   

Though the forces in displacement mode, say less than 15kn, should be way less than when foiling at 50kn, when the manoeuvres will also be very much faster.

It will be interesting to find out why the arms are failing. It may be a consequence of design, construction, materials or testing. Or some combination.

Share this post


Link to post
Share on other sites

Here is my $0.02.... These boats will never consistantly foil if at all. The team that realizes this first will win the AC. 

Share this post


Link to post
Share on other sites
42 minutes ago, RATM said:

These boats will never consistantly foil if at all.

The two down scale boats foil well - especially the Mule. I don't see why the full sized versions won't foil - and foil well. What makes you think the AC75 won't foil?

  • Like 2

Share this post


Link to post
Share on other sites