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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

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18 hours ago, WCB said:

Maybe he should be forced to buy an ad since he's looking to solicit a sugar daddy who will build his boat.

I wouldn't come to SA to raise money to fund this project. However, if I wanted to know what the average person with some familiarity with sailing thought of the Crossbow fl, I couldn't do better than partake of the abounding "wisdom" available here. Luckily for me a couple of above average forumites have  responded for which I am also grateful.

Crossbow fl 161SA + one ft 2 (1).jpg

Crossbow fl-trapwing system-DSS insignia best so far -.jpg

Crossbow fl-primer 006.JPG

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Yet another re–post of images you've already posted 4 or 5 times on the previous page (and many times in other places).

It's coming up to 10 years since you started on this concept and you still don't have anything even remotely resembling a working model, much less a detailed design of the most important and innovative components.

Please see Creativity Is Not Enough (Theodore Levitt, Harvard Business Review)

Quote

Ted Levitt, a former editor of HBR and one of the most incisive commentators on innovation to have appeared in our pages, takes dead aim at the assumption that creativity is superior to conformity. He argues that creativity as it’s commonly defined—the ability to come up with brilliantly novel ideas—can actually be destructive to businesses. By failing to take into account practical matters of implementation, big thinkers can inspire organizational cultures dedicated to abstract chatter rather than purposeful action. In such cultures, innovation never happens—because people are always talking about it but never doing it.

My emphasis.

Please do not re–post anything you've already posted in this thread. Reference it if you must, but do not re–post it.

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1 hour ago, RobG said:

Yet another re–post of images you've already posted 4 or 5 times on the previous page (and many times in other places).

It's coming up to 10 years since you started on this concept and you still don't have anything even remotely resembling a working model, much less a detailed design of the most important and innovative components.

Please see Creativity Is Not Enough (Theodore Levitt, Harvard Business Review)

My emphasis.

Please do not re–post anything you've already posted in this thread. Reference it if you must, but do not re–post it.

I thought you were gone?* That you come back and make such a completely and incredibly false statement makes me wonder why you waste your time? There have been NUMEROUS working models testing the single most critical component of the boat-the movable ballast system. And the system works well and is easy and lots of fun to learn to sail. 

And this exceptionally uninformed statement is totally wrong and just simply made up out of thin air by you! Again, why do you waste time with your own bullshit?! You make no credible effort to understand this concept and just fabricate total horseshit-but I don't understand why you spend your time on such an unhelpful and unproductive waste of your time??!

* "Yeah, sorry, I'm outta here."

Some of the working models that have tested the Trapeze Power Ballast System--and a new boat with the most advanced version of the system yet will be sailing relatively soon:

 

Scow with PBS 3 - Copy.JPG

Melges 24 RC Power Ballast System.jpg

Micro foiler 1.jpg

2007-01-25 11.06.53.jpg

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Crossbow fl and Model Testing:

Some people have a mental block when it comes to using RC models to test the characteristics of a fullsize design or to just explore a concept to be used on fullsize sailboats. Problem is that most likely they have no idea how accurate such testing can be-and may not know how many recognized designers have used RC models and static models to test various aspects of their designs. It is true that you have to know what you can test at model size and what you can't test. I was lucky enough to work with Dr. Sam Bradfield one summer when he used one of my large Flyer Cubed RC trimarans to test the foil configuration for his 40' Skat. We tested the rig postion relative to the foils, the CG relative to the foils, the boats balance and more. We could not (accurately) test the foil section, only the foil configuration and to a large extent foil planform and area. 

On Crossbow the testing of the Trapeze Power Ballast System on various RC models has led  to development that will translate directly to the fullsize boat and has saved thousands of dollars and hundreds of hours of development time.

-----------------------------

Some of the well known designers that have used RC model testing to develop their boats and or a concept include:

Greg Ketterman(Hobie Trifoiler), Paul Larsen(SailRocket), Alain Thebault(Hydroptere), Dr. Sam Bradfield(SKAT), Yves Parlier(60' cat),
Hugh Welbourn(DSS), Bill Burns(CBTF), and many others.
RC model testing works and is a valuable development tool that can save time and money.

pix credits top to bottom: Bradfield(SKAT), Thebault(Hydroptere), Yves parlier(60'cat):

Hydrosail-flyer 3 test model.jpg

31.jpg

parliers cat model.jpg

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Thank you for regurgitating yet again stuff you've already posted multiple times on the previous page and elsewhere over the last many years. I have no idea why you think it's proof of anything, nor why relentlessly re–posting it will serve any useful purpose.

To make it clear, the sliding weight system in your images does not address any of the challenges of your tilting, swiveling, sealed tube system. They have been pointed out to you over the years (such as how the tilting/swiveling mechanism is controlled or how the sealed beam is controlled or what is the fail—safe if the battery dies with the weight and beam at full extension). You've not addressed any of them with anything more than the most cursory of explanations.

If you really have "a new boat with the most advanced version of the system yet" then post pictures of that.

PS.
Your last post has gone up a font size. I guess that's the internet version of translation by volume.

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An old saying...There's the steam that blows the whistle, and the steam that turns the wheels. All we've seen so far is a lot of whistle-tooting.

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23 hours ago, RobG said:

Yet another re–post of images you've already posted 4 or 5 times on the previous page (and many times in other places).

It's coming up to 10 years since you started on this concept and you still don't have anything even remotely resembling a working model, much less a detailed design of the most important and innovative components.

Please see Creativity Is Not Enough (Theodore Levitt, Harvard Business Review)

My emphasis.

Please do not re–post anything you've already posted in this thread. Reference it if you must, but do not re–post it.

the good old cult of innovation. let's all strive for moonshot reinventions to solve problems that were solved decades ago!

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22 hours ago, dgmckim said:

the good old cult of innovation. let's all strive for moonshot reinventions to solve problems that were solved decades ago!

Incredible!

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On 12/7/2017 at 4:18 PM, Doug Lord said:

Crossbow fl 2018 :

Summary of Features and Specifications:
-------------------------------
Features:
1) Self-bailing cockpit
2) Boat rightable from 90+ degree knockdown by crew w/o crew movement using the wing regardless of the position of the sliding ballast.
a. ballast wing is sealed and has buoyancy much greater than that required to float the ballast sliding inside.
b. ballast+ wing can be moved manually or electrically faster than a crew on a trapeze could move.
3) Rig utilizes modified rotating, A Class wing mast, sealed with masthead buoyancy to prevent turtling,
4) Ballast wing pivots:
a. to allow trailering
b. to move ballast aft when required with wing extension.
c. also pivots athwartship to keep weight low to windward and to keep lee side of wing clear of water.
5) Ballast is adjustable in 10lb increments,
6) Boat can be sailed off a beach,
7) Boat features an asymetrical spinnaker, an underdeck spinnaker chute and retractable bow pole,
8) Seating arrangement: (NEW) .
a. The skipper will sit relatively low in the boat on a seat that will manually or electrically rotate 180 degrees. This will allow the skipper to steer with his or her aft hand and handle the single sheet and Trapeze Power Ballast System with their forward hand. For Class racing weight equal to the difference between 250lb. and the skippers weight will be carried in a ballast compartment under the seat. 250lb is the maximum crew weight for racing.
9) Large, buoyant "spray rails" act to help provide a dry ride and knockdown recovery,
10) Self-tending jib with variation of Swift solo single sheet system.
11) Boat uses removable, "plug-in" DSS foils for greatly increased power to carry sail with speed.
12) The new changes effectively "turbo" the boat even allowing for windward planing.
13) Boat has an extremely wide crew weight range: approx 100lb to 250lb for normal sailing. All ratios are based on 250lb crew and would drastically improve with lighter crew weight. For class racing, it would be my desire to see a class adopt the maximum crew weight as standard with lighter crew carrying weight under the seat-or perhaps two "weight classes"-whatever it takes to encourage the widest participation.
-------------
Specifications: (changes are to be expected)
Hull length-15.6' 
Beam- 4.75'
---at waterline-3.75'
Sail Area-(boat will use a carbon A Class wing mast from Matt McDonald/ Falcon Marine LLC, laid up specifically for this boat).
--upwind- 161 sq.ft.
-- downwind- 290 sq.ft.
Weight-sailing weight w/o crew- 223lb which includes:
--hull, rig, foils-124lb
--Trapeze Power Ballast System:
---wing-21lb. @ 12'-16' length overall, pivots for transport, and moving weight aft.
--- max ballast 78lb(8 pieces of lead-removable-.25" X 8" X 12"-about 9.72lb each)
Max Crew weight: 250lb-boat is designed as a singlehander.
All up sailing weight including crew-473lb
DSS Foils: each 1.63 sq.ft.( 6" X 39") 6.5/1 aspect ratio, Welbourn section.
Electrical System for moving ballast: Engineered by Rick Willoughby, who did the original "ballast mover" spread sheet.
-------
Ratios-
see Eric Sponbergs Design Ratio's PDF below
-------------
DLR=55.6 
---
SA/D=
--upwind-42.48
--downwind- 76.78
---
SA/ws-
--3.7/1 
--3.48/1 including DSS foil
---
SCP/Total weight= .3 and .34 if upwind RM from DSS foil is counted.
===========

 

Attached Files:

  •  

 

 

 

 

Top Crossbow fl,  Bottom Crossbow XPRO(possible experimental prototype) 

pix by dl

Crossbow fl-primer 005.JPG

Crossbow XPRO 004.JPG

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All the same crap once again with a couple of chairs added this time, still no full size sailing prototype, but what else would we expect from possibly the biggest bullshitter on this forum.

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Doug I'll keep this brief is I don't interrupt your important work...

You are so full of shit , do something real, actual size and with real people sailing it -- then others may be interested.

Stop polluting interesting conversations with your fantasies.

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I’m going to give my kids some balsa and see what they come with. The I’ll post the same pics for 10 years. Sound good

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"

19 hours ago, Doug Lord said:

2) Boat rightable from 90+ degree knockdown by crew w/o crew movement using the wing regardless of the position of the sliding ballast.

Can you please explain how this is achieved? You have an immobile (disabled) crew sitting in a seat (strapped in?). Correct? 

Just how do you get the centre of effort far enough from the centre of bouyancy to right the boat when the wing is now vertical? Moving the weight about inside the wing doesn't do anything constructive towards moving the C-o-E towards where it needs to be, because it - the wing - is now vertical.

Righting a traditional dinghy, and I know that you will respond that Crossbow-fl isn't a traditional dinghy, requires weight on the end of the extended centre- or dagger-board. That's usually a human.

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44 minutes ago, GBRNoah said:

"

Can you please explain how this is achieved? You have an immobile (disabled) crew sitting in a seat (strapped in?). Correct? 

Just how do you get the centre of effort far enough from the centre of bouyancy to right the boat when the wing is now vertical? Moving the weight about inside the wing doesn't do anything constructive towards moving the C-o-E towards where it needs to be, because it - the wing - is now vertical.

Righting a traditional dinghy, and I know that you will respond that Crossbow-fl isn't a traditional dinghy, requires weight on the end of the extended centre- or dagger-board. That's usually a human.

It works because the buoyancy of the wing is several times that required to float the ballast. If the wing is extended max to windward and the boat knocked down, the crew can simply move the joystick to immerse the wing(helped by the weight in the wing). As the wing is immersed it pivots about the fore and aft axis moving the immersed CB of the wing  to increase righting moment. The boat will start to right itself from the point that the lee wingtip is immersed. This has been tested on a model and works well. No ballast keel necessary.....

The wing will move fast enough that the crew could move it during the knockdown, likely preventing the boat from ever reaching 90 degrees. 

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3 hours ago, Doug Lord said:

It works because the buoyancy of the wing is several times that required to float the ballast. If the wing is extended max to windward and the boat knocked down, the crew can simply move the joystick to immerse the wing(helped by the weight in the wing). As the wing is immersed it pivots about the fore and aft axis moving the immersed CB of the wing  to increase righting moment. The boat will start to right itself from the point that the lee wingtip is immersed. This has been tested on a model and works well. No ballast keel necessary.....

The wing will move fast enough that the crew could move it during the knockdown, likely preventing the boat from ever reaching 90 degrees. 

Jesus that’s funny. The weight helps move the sealed ballast thingy down? You realize that the one thing going for your sealed mini-ama was it’s floats. And now your going to sink it?

stick to models. No one dies.

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As you should realize*, the weight helps the wing move down(from max up) when the boat is at 90 degrees**. Power is required to use the wing to right the boat-manual or electric. But you knew that, right?!

*No, after all this you still don't get it.........

** The question about a knockdown assumes the wing is max out to windward and the boat is knocked over 90 degrees resulting in the wing sticking up if the crew didn't move it during the knock down. From that position the weight helps the wing go down but power is required to push the wing down far enough to right the boat.

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1 hour ago, Raz'r said:
4 hours ago, Doug Lord said:

It works because the buoyancy of the wing is several times that required to float the ballast. If the wing is extended max to windward and the boat knocked down, the crew can simply move the joystick to immerse the wing(helped by the weight in the wing). As the wing is immersed it pivots about the fore and aft axis moving the immersed CB of the wing  to increase righting moment. The boat will start to right itself from the point that the lee wingtip is immersed. This has been tested on a model and works well. No ballast keel necessary.....

The wing will move fast enough that the crew could move it during the knockdown, likely preventing the boat from ever reaching 90 degrees. 

Jesus that’s funny. The weight helps move the sealed ballast thingy down? You realize that the one thing going for your sealed mini-ama was it’s floats. And now your going to sink it?

stick to models. No one dies.

You just don't appreciate the genius of it all......... the wing+ ballast is safe because the bouyancy of the wing is many times the weight of the ballast, and yet the bouyant wing submerses easily because of the weight of the ballast!

Completing a working prototype of Doug Lord's sailing contraption will be the first step of the world's first practical perpetual-motion machine!

BTW Doug have you spec'd the actuators needed to drive this wing back & forth and round & round etc etc? And not only have the power necessary to pull the boat upright (got a calculation for that, in ft/lbs or whatever other measurement you like), but also to move the ballast super-quick for hi-performance sailing?

-DSK

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2 hours ago, Steam Flyer said:

You just don't appreciate the genius of it all......... the wing+ ballast is safe because the bouyancy of the wing is many times the weight of the ballast,and yet the bouyant wing submerses easily because of the weight of the ballast!

Completing a working prototype of Doug Lord's sailing contraption will be the first step of the world's first practical perpetual-motion machine!

BTW Doug have you spec'd the actuators needed to drive this wing back & forth ? And not only have the power necessary to pull the boat upright (got a calculation for that, in ft/lbs or whatever other measurement you like), but also to move the ballast super-quick for hi-performance sailing?

-DSK

What a stupid half-ass distortion of what I said!!

Yes.

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42 minutes ago, Doug Lord said:
3 hours ago, Steam Flyer said:

BTW Doug have you spec'd the actuators needed to drive this wing back & forth ? And not only have the power necessary to pull the boat upright (got a calculation for that, in ft/lbs or whatever other measurement you like), but also to move the ballast super-quick for hi-performance sailing?

-DSK

What a stupid half-ass distortion of what I said!!

Yes.

And?

You've had your specs on weight questioned several times, generally you respond by attacking the questioner. Actuators and trunnions and bearings are heavy.

What actuators would you use? How do you plan to incorporate these features into a boat which ends up being lighter than most hi-performance sailboats that don't have them?

-DSK

 

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1 hour ago, fastyacht said:

" . ballast+ wing can be moved manually or electrically faster than a crew on a trapeze could move. "

Doug, this is very hard to believe.

 

That's why I asked about actuators. I have some experience with various kinds, in industry........  seems likely to be heavy and a power hog, if there is one that can meet his specs at all. And it's going to be kinda spendy, too.

-DSK

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My experience with electrical stuff in small, wet boats in salt water leads me to the conclusion that it is a huge hassle to keep the electrical stuff from corroding and shorting out. It will either fail a lot or require tons of maintenance to keep it all alive. And honestly, this boat appears to me to be the answer to a question nobody is asking. It doesn't appear to do anything a Weta can't do at a sixth of the cost. 

 

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6 hours ago, Doug Lord said:

As you should realize*, the weight helps the wing move down(from max up) when the boat is at 90 degrees**. Power is required to use the wing to right the boat-manual or electric. But you knew that, right?!

*No, after all this you still don't get it.........

** The question about a knockdown assumes the wing is max out to windward and the boat is knocked over 90 degrees resulting in the wing sticking up if the crew didn't move it during the knock down. From that position the weight helps the wing go down but power is required to push the wing down far enough to right the boat.

Weight helps the wing go down. You realize that means it counters what your trying to do...  but you’re an idiot so I guess, no

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56 minutes ago, MisterMoon said:

My experience with electrical stuff in small, wet boats in salt water leads me to the conclusion that it is a huge hassle to keep the electrical stuff from corroding and shorting out. It will either fail a lot or require tons of maintenance to keep it all alive. And honestly, this boat appears to me to be the answer to a question nobody is asking. It doesn't appear to do anything a Weta can't do at a sixth of the cost. 

 

Thats interesting. There are sailboats like the Martin 16, SKUD, and quite a few others designed for people with some disabilities that very successfully use electrical equipment for steering, sheeting etc. Depends on how it's designed. The Crossbow fl wing will move ballast  center to 12' out in about  2-3 seconds and do it all day for two days w/o recharging. The new system will even be more efficient and a little quicker-and may be radio controlled. The Ballast Mover spreadsheet is in the boatdesign thread but it's a little dated but interesting to fool with.

Oh, and Crossbow fl is rightable by the crew with very little hand movement(no body movement, no swimming) , or ,probably optionally, automatically neither of which the Weta can do! And the Crossbow fl won't turtle like the Weta does.

The key is speed and moving up to 78lb.

 

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13 minutes ago, Raz'r said:

Weight helps the wing go down. You realize that means it counters what your trying to do...  but you’re an idiot so I guess, no

You just don't get it.

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If you just said outright that the objective of the boat was to create an earnestly fun boat for disabled sailors, this would be a good deal better received. It seems that you're asserting to everyone that sailing will be revolutionized by restricting free motion and requiring a seatbelt. This rankles many, but is rarely the focus of discussion.

DRC

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3 hours ago, Dave Clark said:

If you just said outright that the objective of the boat was to create an earnestly fun boat for disabled sailors, this would be a good deal better received. It seems that you're asserting to everyone that sailing will be revolutionized by restricting free motion and requiring a seatbelt. This rankles many, but is rarely the focus of discussion.

DRC

I tried this with him, and I agree with you. But nope, I got lambasted that I just didn’t see the future for all sailors.

 

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21 hours ago, Doug Lord said:

It works because the buoyancy of the wing is several times that required to float the ballast. If the wing is extended max to windward and the boat knocked down, the crew can simply move the joystick to immerse the wing(helped by the weight in the wing). As the wing is immersed it pivots about the fore and aft axis moving the immersed CB of the wing  to increase righting moment. The boat will start to right itself from the point that the lee wingtip is immersed. This has been tested on a model and works well. No ballast keel necessary.....

The wing will move fast enough that the crew could move it during the knockdown, likely preventing the boat from ever reaching 90 degrees. 

So you have the masthead at water level, and your magic weighted, but buoyant, wing lifts the hull out of the water. Where's the CoG? How do you stop water ingress into this supremely clever device that slides athwartships and fore/aft AND has ballast moving about inside it? Where's the power source? Where are the motors?

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9 hours ago, Dave Clark said:

If you just said outright that the objective of the boat was to create an earnestly fun boat for disabled sailors, this would be a good deal better received. It seems that you're asserting to everyone that sailing will be revolutionized by restricting free motion and requiring a seatbelt. This rankles many, but is rarely the focus of discussion.

DRC

I have never said the boat would require a seatbelt!!!! Further, I've said words to the effect that this boat would be an earnestly fun boat for all sailors-not just disabled sailors.

From post 11:

Crossbow fl is not specifically directed at handicapped sailors-it is directed at all sailors that would enjoy a spectacular new way to sail a monohull fast without the physical demands of current performance monohulls.

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2 hours ago, GBRNoah said:

So you have the masthead at water level, and your magic weighted, but buoyant, wing lifts the hull out of the water. Where's the CoG? How do you stop water ingress into this supremely clever device that slides athwartships and fore/aft AND has ballast moving about inside it? Where's the power source? Where are the motors?

It's not magic-its science!

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7 minutes ago, Doug Lord said:

It's not magic-its science!

So answer the damn questions then!

Where's the CoG?

How do you stop water ingress into this supremely clever device that slides athwartships and fore/aft AND has ballast moving about inside it?

Where's the power source?

Where are the motors?

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I remember when dinghy anarchy used to be a safe place from the fool of foils and bathtub toys, LOL.  Just FYI, the ignore function still works great!!

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On 12/7/2017 at 4:18 PM, Doug Lord said:

Crossbow fl 2018 

Summary of Features and Specifications:
-------------------------------
Features:
1) Self-bailing cockpit
2) Boat rightable from 90+ degree knockdown by crew w/o crew movement using the wing regardless of the position of the sliding ballast.
a. ballast wing is sealed and has buoyancy much greater than that required to float the ballast sliding inside.
b. ballast+ wing can be moved electrically faster than a crew on a trapeze could move. NEW- Single electric motor inside boat attached to line from each end of wing allows very fast athwartship movement. Battery inside boat with enough capacity for two days sailing w/o recharging with very frequent wing movement. With a 14' wing , ballast moves 12' to windward of the heeled CB. Total RM from 14' wing=1083ft.lb. Total RM wing+ crew=1583 ft.lb. Line from center of boat, each side, to sealed roller and from roller to ballast allows weight to move when wing is moved. Basic wing control system has been tested on several RC boats over 20+ years and works extremely well. Control is the same as on an rc version using a weatherproof joystick.

3) Rig utilizes modified rotating, A Class wing mast, sealed with masthead buoyancy to prevent turtling,
4) Ballast wing pivots:
a. to allow trailering
b. to move ballast aft when required with wing extension.
c. also pivots athwartship to keep weight low to windward and to keep lee side of wing clear of water.
5) Ballast is adjustable in 10lb increments via watertight hatch. NEW
6) Boat can be sailed off a beach,
7) Boat features an asymetrical spinnaker, an underdeck spinnaker chute and retractable bow pole,
8) Seating arrangement: (NEW 2013) .
a. The skipper will sit relatively low in the boat on a seat that will manually or electrically rotate 180 degrees. This will allow the skipper to steer with his or her aft hand and handle the single sheet and Trapeze Power Ballast System with their forward hand. For Class racing weight equal to the difference between 250lb. and the skippers weight will be carried in a ballast compartment under the seat. 250lb is the maximum crew weight for racing.
9) Large, buoyant "spray rails" act to help provide a dry ride and knockdown recovery,
10) Self-tending jib with variation of Swift solo single sheet system.
11) Boat uses removable, "plug-in" DSS foils for greatly increased power to carry sail with speed.
12) The new changes effectively "turbo" the boat even allowing for windward planing.
13) Boat has an extremely wide crew weight range: approx 100lb to 250lb for normal sailing. All ratios are based on 250lb crew and would drastically improve with lighter crew weight. For class racing, it would be my desire to see a class adopt the maximum crew weight as standard with lighter crew carrying weight under the seat-or perhaps two "weight classes"-whatever it takes to encourage the widest participation.
-------------
Specifications: (changes are to be expected)
Hull length-15.6' 
Beam- 4.75'
---at waterline-3.75'
Sail Area-(boat will use a carbon A Class wing mast from Matt McDonald/ Falcon Marine LLC, laid up specifically for this boat).
--upwind- 161 sq.ft.
-- downwind- 290 sq.ft.
Weight-sailing weight w/o crew- 223lb which includes:
--hull, rig, foils-124lb (target)
--Trapeze Power Ballast System:
---wing-21lb. @ 12'-16' length overall, pivots for transport, and moving weight aft.
--- max ballast 78lb(8 pieces of lead-removable-.25" X 8" X 12"-about 9.72lb each)
Max Crew weight: 250lb-boat is designed as a singlehander.
All up sailing weight including crew-473lb
DSS Foils: each 1.63 sq.ft.( 6" X 39") 6.5/1 aspect ratio, Welbourn section.
Electrical System for moving ballast: Engineered by Rick Willoughby, who did the original "ballast mover" spread sheet.
-------
Ratios-
see Eric Sponbergs Design Ratio's PDF below
-------------
DLR=55.6 
---
SA/D=
--upwind-42.48
--downwind- 76.78
---
SA/ws-
--3.7/1 
--3.48/1 including DSS foil
---
SCP/Total weight= .3 and .34 if upwind RM from DSS foil is counted.
===========

 

Attached Files:

  •  

Crossbow fl 161SA + one ft 2 (1).jpg

Crossbow fl-primer 006.JPG

Crossbow fl 161SA + one ft 2 (1).jpg

Crossbow fl-primer 006.JPG

 

Updated spec sheet above. This is preliminary information and will not be complete until a fullsize prototype is built and tested. The basic concept of the boat and sailing with a Trapeze Power Ballast System has been tested with RC models over the last 20+ years.

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3 minutes ago, Doug Lord said:

 

Updated spec sheet above.

I still don't see any spec for the batteries or the actuators, both of which are major components.

A back-of-envelope sketch is great for laying out general concepts and configuration, but this is not a design. A DESIGN includes materials, layup schedule (and/or req moments of inertia), for a mechanical assembly like the trunnions, slides, and actuators it must include a force diagram, some dimensions (don't forget the square surface area of foils, that's kinda important)....... this is just a childish kludge.

If one of my high school sailing students had come to me with this, I'd be glad to go over it bit by bit and show him what is needed to produce a working design. An adult pretending to be a designer who won't answer basic questions?

-DSK

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You know, if everyone actively avoided this thread it would probably go away. What’s the point of arguing with someone who actively refuses to listen or participate in a non-hostile way? There’s a point where it’s not worth the effort

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