sailing, speed record

[Sean Herron]

Hello...

Then there is the crazy schmuck (sorry to introduce a new pronoun) who thought it would be fun to hold up a sheet stretched across bamboo while wearing ice skates on Lake Erie...

Was that maniac a 'boat' - or just another lunatic - nope - just a Sean...

Or the sail car I built in high school shop class...

Or the long skate board with an early sail board rig - WHO CARES - I had a good time...

Hehehehe...

Best of...

SH.

[Chris Krumm]

Dave - time to get picky. Something that displaces it's own weight in water doesn't include a stone, unless the specific gravity of said stone is less than or equal to water. Most stones sink and displace an equal volume of water, but not an equal weight of water ('cept for those floating lava rocks I remember being amazed to see as a kid). That said, I'm cool with kites and have followed your work with interest for a number of years.

So, Sean - if I buy your definition of a boat, what does that make it if it's holed and sunk? A " sunken boat," a "sunken piece of %*#@," or perhaps, a "stone?"

Chris

[Sean Herron]

Hello...

I am going to go get my favourite blanket - and just begger'uf...

SH.

[foxxaero]

Well, Sean... I'm not sure, ...but I think we can let you go 'This time'

hehehe!!!

I will try to find a conversation with Jon on the Windjet site and post it here.

It was Very thought-provoking ... made me stop and think.

Aeronautical engineers will understand his thinking better than I.

By the time ya get to 50 knots in a sailing vessel, ya better have some aerodynamicists on board in the engineering department.

My reservations on his ability to pull it off depend upon my ignorance of aerodynamic theory.

As I said, "we shall see" !

The state we are in today (in advanced boat design) is the blending of hydrodynamic and aerodynamic principles to develop craft capable of operating at the the air - water interface to best advantage.

Only time will tell if Richard Jenkins (and the Windjet Team), OR Jon Howes (and the Monofoil Team), OR 'others' successfully blend these technologies to come up with the winning combination.

Cheers

Russ

[Sean Herron]

Hello...

OK all that banter was fun - but lets be realistic - this all is the fringe - beyond a doubt - it is the Formula One or the Nascar of the sailing bung heads - and in many cases - carries the same ego, same drive, same fascination as same - I only wish it had same sponsorship and TV time...

I love it, and I love it because the interfaces of water and air are so damned extreme - and are more extreme than they are on 'the horse power to rubber and aerodynamics' motor track maniacs - however the track racers can experiment within the envelope of true human comabatants - unlike the canyon racers of the outer speed fringe of the sailor clique - you will now argue the salt flats against same - I KNOW...

I follow the extremes - yet I also try to interpret them within the 'current' production boundaries, the boundaries of newcomers to the sport and its science and the probability of the extreme engineering trickling down into the production markets, and the average lazy flop who goes to McDonalds and then to the boat - call me boring...

I know that I remain a Devils' advocate - and I know that same can kill the spirit of a kid with an idea - and I won't - it's all in the balance isn't it...

Some have a fascination with speed and extremes - some have a fascination with how certain BBQ sauces caramelize and blacken faster than others at certain temperatures while BBQ'ing sausages at anchor, with the kids snorkeling about ('SCRAPE THOSE BARNACLES OFF THE TRANSOM YOU D-MINUS IN ALGEBRA - NO SON OF MINE - YOU ARE LUCKY TO BE HERE - I SHOULD HAVE LOCKED YOU IN A CLOSET) just 15' from a dog walking beach that has many a jogger babe (woman running) on it...

So I am just now loosing track of my pizza delivery boy - got to go...

SH.

[foxxaero]

Here's the link to some design conversations posted on the Windjet site ... (maybe we are all lunatics) hehehe

http://www.windjet.co.uk/Supporters/.../posts/669.php

Also heard from Richard Jenkins, and although he still refuses to provide info on his new radical Windjet Boat design, he advises me that the pics posted on my site are the result of erroneous conclusions... (not Big News to me ... I've been known to be wrong before!)

Cheers

Foxx

[afam]

Dear Sir,

My name is Yusuf Ubanwa(San), I am a private attorney and I have a client
who is interested in investing some good money in your country.
My client is a very important and prominent person who has mandated me to
contact you for a very important business transaction. My client is by name
Mrs. Maryam Abacha and she is the wife of a late military
head of state in my country.
Her husband late general Sanni Abacha made a lot of money through oil
proceeds during his tenure in office. In-fact, it was discovered after his
death that he was worth well over $4.5 billion united states dollars and
some of this money was retrieved after he died while some was recovered from
officials that served under him during his reign as president of Nigeria.
The truth of this case is that my client despite the
problem she is going through now, she still has a lot of money in her
possession. which she intends to invest outside our country.
What my client needs from you now is a reliable account where she can
transfer some money but mind you, all the money in her possession can not
leave at once because she needs to build confidence and trust in someone who
would not expose her plan to remit and possibly invest in your country. So
she has agreed that I should make arrangement for the transfer of
$60.5million united states dollars and you are free
to negotiate your mode of compensation even as she intends to invest the
money in your country.
Please, do not hesitate to indicate your view of this request by contacting
me immediately you receive this mail, so that the necessary arrangements can
be made for the money to leave immediately.
Due to the present situation of my client, I would be happy if this request
can be kept a secret.
I would also like to note that there is no risk involved.
I hope my client would be happy investing with you.
Please kindly send down your reply through my
personal e-mail address barryu1@hotmail.com)and my personal
Phone number:234-8023343821



Thanks,

Yusuf Ubanwa(San)

[afam]

Dear Sir,

My name is Yusuf Ubanwa(San), I am a private attorney and I have a client
who is interested in investing some good money in your country.
My client is a very important and prominent person who has mandated me to
contact you for a very important business transaction. My client is by name
Mrs. Maryam Abacha and she is the wife of a late military
head of state in my country.
Her husband late general Sanni Abacha made a lot of money through oil
proceeds during his tenure in office. In-fact, it was discovered after his
death that he was worth well over $4.5 billion united states dollars and
some of this money was retrieved after he died while some was recovered from
officials that served under him during his reign as president of Nigeria.
The truth of this case is that my client despite the
problem she is going through now, she still has a lot of money in her
possession. which she intends to invest outside our country.
What my client needs from you now is a reliable account where she can
transfer some money but mind you, all the money in her possession can not
leave at once because she needs to build confidence and trust in someone who
would not expose her plan to remit and possibly invest in your country. So
she has agreed that I should make arrangement for the transfer of
$60.5million united states dollars and you are free
to negotiate your mode of compensation even as she intends to invest the
money in your country.
Please, do not hesitate to indicate your view of this request by contacting
me immediately you receive this mail, so that the necessary arrangements can
be made for the money to leave immediately.
Due to the present situation of my client, I would be happy if this request
can be kept a secret.
I would also like to note that there is no risk involved.
I hope my client would be happy investing with you.
Please kindly send down your reply through my
personal e-mail address barryu1@hotmail.com)and my personal
Phone number:234-8023343821



Thanks,

Yusuf Ubanwa(San)

[Sketch]

Mr. Yusuf Ubanwa,

Your offer reads like one I received while working for the US Department of State in Dakar Senegal. I presented it to the Regional Security Officer, and he indicated that it was a complete SCAM! In fact this type of scam more often than not originates in Nigeria and plays on victim's greed ("there are now some probloems, we need a little money to free up the rest", possibly going so far as to invite the person to actually come to Lagos). The scam distances it's victims from the authorities because they are involved in money laundering.

Sir, I do not know you, your client, nor your intentions. Nonetheless this is the wrong place to be fishing for business. Take it somewhere else.

Kevin Barry

[Kiteship]

Originally Posted by foxxaero

Here's the link to some design conversations posted on the Windjet site ... (maybe we are all lunatics) hehehe

http://www.windjet.co.uk/Supporters/.../posts/669.php

It is not possible to "sail" without at least one foil (aero or hydro) in each of two fluids. This is the definition of sailing. It IS possible to buoyantly support the craft--and payload--in either air or water--or a combination of both.

What many forget when considering "dynamic lift" of speedsailing boats is the induced drag of such lift and that drag's effect on top speed. Granted that any form of "holding up" the boat will cause drag; one must realistically compare the drag of both a "reference" source (such as ordinary buoyancy of long thin hulls) with the drag of the replacement system--at the target boat speed. If you cannot significantly reduce this drag, then the "alternate" system will not be faster than the reference system.

It is also necessary to do an "energy budget" at all intermediate speeds to be sure the system (boat + rig) is capable of acellerating to the target speed. This is also often overlooked, resulting in boats which cannot hit their targets. ("all intermediate speeds" might include the big drag hump when displacement hulls and hydrofoils are both at their max drag; or a draggy lifting wing + planing hull are at a low speed when a small and efficient aero element isn't yet developing much lift, etc, etc)

FWIW, very few speed sailors have considered lighter than air lift (heliuim, etc), which is a novel way of "negating" gravity's effect and can be (theoretically of course) far more effficient than any dynamic lift.

Dave Culp
Dave Culp Speedsailing

[foxxaero]

Thanks again for your input Dave, I have been following your Kite-sail projects for some years. The Kite-Tug concept you have proposed is very interesting and reminds me of what Jon & Johan refer to as a 'wind-gradient engine'. Here's a diagram of Johans concept -

http://foxxaero.homestead.com/sailing_aerofoil.html

It appears to me that this concept goes way beyond 'sailing'. What do you think???

Cheers

Russ

Originally Posted by Kiteship

It is not possible to "sail" without at least one foil (aero or hydro) in each of two fluids. This is the definition of sailing. It IS possible to buoyantly support the craft--and payload--in either air or water--or a combination of both.

What many forget when considering "dynamic lift" of speedsailing boats is the induced drag of such lift and that drag's effect on top speed. Granted that any form of "holding up" the boat will cause drag; one must realistically compare the drag of both a "reference" source (such as ordinary buoyancy of long thin hulls) with the drag of the replacement system--at the target boat speed. If you cannot significantly reduce this drag, then the "alternate" system will not be faster than the reference system.

It is also necessary to do an "energy budget" at all intermediate speeds to be sure the system (boat + rig) is capable of acellerating to the target speed. This is also often overlooked, resulting in boats which cannot hit their targets. ("all intermediate speeds" might include the big drag hump when displacement hulls and hydrofoils are both at their max drag; or a draggy lifting wing + planing hull are at a low speed when a small and efficient aero element isn't yet developing much lift, etc, etc)

FWIW, very few speed sailors have considered lighter than air lift (heliuim, etc), which is a novel way of "negating" gravity's effect and can be (theoretically of course) far more effficient than any dynamic lift.

Dave Culp
Dave Culp Speedsailing

[Jon Howes]

Russ,

I think the Windjet forum thread that caused the fun was this one referring to an old experiment of mine. The point was to show a means of sailing with different parts of the machine in different airflows:

"Time out from "Monofoil" to join in with this bit of fun:
Equipment,

One stable (ie, single line)kite,
One small lightweight parachute of similar area to the kite,
One set of car keys,
One big open space with a breeze,
One mobile telephone.

Method,

Attach car keys to the kite string with about 150 feet of string to the kite.
Tie the parachute to the keys with a short line (about 4 to 5 feet).
Launch the kite.
Run towards the kite (downwind) such that the kite continues to fly but you feel a headwind, ie, slower than the high altitude breeze but faster than that at ground level.
Let go of the keys and parachute.
Use the mobile telephone to call your wife for a spare set of keys.
Drive home and ponder on todays lesson.

This works although I did not use car keys.

A wind gradient engine is exactly analogous to a sailing boat. A sailing boat requires a shear layer, either air-water, air-ground, air-ice, or, if different wind speeds can be experienced by the same craft, air-air. Replace the parachute with a controllable aerodynamic device (another kite, etc) and you now have a viable machine.

Sea birds use exactly this principle by flying between the shear layers to exchange momentum (dynamic soaring). There is nothing physically wrong with the principle and there are many theoretical ways of achieving a similar result. Hang on to your car keys!

Unfortunately, these ideas are neither original (I first heard conceptually similar ideas in 1989), likely to produce a particularly fast machine, or mine. However, someone should have a proper go..."

To do this with a more useful vehicle I would probably go for either a rotary wing where the downwind part of the rotation path is elevated and the upwind path is close to the surface, this is similar to dynamic soaring as performed by seabirds, the other approach would be to use a form of wind turbine where the lower half of the turbine is in the slack low flow and the upper part is in the enrgetic upper flow, this could also be divided into propellor and turbine, prop low, turbine high. Same principle as all the above but I don't have time...

I look forward to a plague of kite-delivered car keys in the near future.

Jon.

[foxxaero]

Thanks Jon, yep that was the post I was referring to ... :-)

Correct me if I am wrong, but this is a different concept to the Monofoil ... no?

I recognize that you are very busy with the development of the Monofoil, but can you expand a bit on this wind gradient engine thingy? The addition of helium filled kite-wings seems that it could add to the concept? I must confess that I am having trouble following this line of thinking.

I understand pictures better than words. The 'sailing aerofoil' concept posted by Johan (link posted earlier) looks viable to me as a sail-powered 'aircraft', but I don't understand how this concept could be classified as a 'boat' under current IMO guidelines.

What am I missing here?

Apologies, due to high traffic my site 'Worlds Most Radical Boat Designs' is off-line until the 15th so previous links I have posted won't be available again til then.

Cheers

Russ

[Jon Howes]

Russ,

This concept is absolutely nothing to do with Monofoil. It also could hardly be described as a boat but just do it anyway and see who complains, however... Since it would be nearly impossible to launch over land a water based option is the most likely approach (so it's not off-topic for this forum. Honest!!

The use of wind gradient is exactly the same as the use of wind over a sail reacted by water flow over a foil or centreboard, the only fundamental difference is that the centreboard is much bigger and uses air instead. Sailing only works because the air is usually moving with respect to water , if it isn't then that is a perfect description of a flat calm. In the case of this concept the upper air is moving with respect to the lower air so the same concept applies. The biggest difference is the need to generate lift and a canted upper rig or kite can provide this. There is absolutely no reason why the lower rig should also not be canted to provide lift as well as long as both rigs are at different heights and hence in different airflows. This brings us neatly to the rotary wing approach (which I think was my idea) in which lift is generated all around the path followed by each rotor blade, the primary difference being that the baldes oscillate such that they fly high downwind and low upwind (simply angle the rotor disc). They will happily autorotate (windmill) during this process in exactly the same way that an autogyro rotor keeps turning. The downwind blade operates at high Cl and low speed and extracts energy while it is carried downwind, the upwind blade operates at low Cl and high airspeed as it penetrates and uses the energy gained on the downwind leg. A pair of counter rotating rotors on opposite ends of a beam should allow some semblance of stability and control and there you have it:- free flight (as in no fuel involved).

The wind turbine approach does the same thing only one turbine stays in the fast flow, the driven propellor stays in the low flow. Hold the whole lot up with a wing and off you go only I suspect that a propellor/turbine combination would extend too far vertically to gain much useful airspeed difference between the two units which brings me to (finally)...

A single wind turbine. The lowest part of the turbine in the slow flow is driven by the upper part of the turbine in the fast flow (sounds like the rotor again?). The lower part could generate thrust and a wing could again hold the whole lot up.

I think that either the rotor or the pair of kites is the way to go. I also don't like helium filled anything as this is unnecessary and gives all sorts of horrible ground handling/parking problems.

Originally Posted by foxxaero

Thanks Jon, yep that was the post I was referring to ... :-)

Correct me if I am wrong, but this is a different concept to the Monofoil ... no?

I recognize that you are very busy with the development of the Monofoil, but can you expand a bit on this wind gradient engine thingy? The addition of helium filled kite-wings seems that it could add to the concept? I must confess that I am having trouble following this line of thinking.

I understand pictures better than words. The 'sailing aerofoil' concept posted by Johan (link posted earlier) looks viable to me as a sail-powered 'aircraft', but I don't understand how this concept could be classified as a 'boat' under current IMO guidelines.

What am I missing here?

Apologies, due to high traffic my site 'Worlds Most Radical Boat Designs' is off-line until the 15th so previous links I have posted won't be available again til then.

Cheers

Russ

Hope this is not too far off topic for the forum.

Jon.

[foxxaero]

Your explanation of wind-gradient helps (I think).

Looking forward to see your full-size Monofoil in action. The video of the model in operation says a thousand words...

http://foxxaero.homestead.com/indrad_006.html

If you have not been following Richard Jenkins progress, he has reactivated his site - looks great! no pics of the new water-version yet...

http://www.windjetproject.com/