17 Oct 2005 07:23:05
Iain Cheyne
Aquaskipper - man-powered hydrofoil

I'm not selling my 1x any time soon, but this is worth a look,
especially the demo video.

http://www.inventist.com/products/aquaskipper.html

"FLY ON WATER WITH THE AQUASKIPPER

Now you can fly above the water on the latest product from Inventist! A
hopping motion propels you forward while the hydrofoil gives you lift.
You will continue to move at speeds of up to 17 miles per hour above
the water, where there is little drag. With the AquaSkipper, you can
ride on waves, try new tricks, and race your friends. Tow it behind a
boat for some extra fun! Any way you use it, the AquaSkipper is fun and
a great way to exercise."

--
Iain Cheyne



17 Oct 2005 07:29:32
bill
Re: Aquaskipper - man-powered hydrofoil


Iain Cheyne wrote:
> I'm not selling my 1x any time soon, but this is worth a look,
> especially the demo video.
>
> http://www.inventist.com/products/aquaskipper.html
>
> "FLY ON WATER WITH THE AQUASKIPPER
>
> Now you can fly above the water on the latest product from Inventist! A
> hopping motion propels you forward while the hydrofoil gives you lift.
> You will continue to move at speeds of up to 17 miles per hour above
> the water, where there is little drag. With the AquaSkipper, you can
> ride on waves, try new tricks, and race your friends. Tow it behind a
> boat for some extra fun! Any way you use it, the AquaSkipper is fun and
> a great way to exercise."
>
> --
> Iain Cheyne

I originally saw it about 1.5 years ago, as the "Trampofoil" and:

http://www.trampofoil.com/



17 Oct 2005 21:31:28
simonk
Re: Aquaskipper - man-powered hydrofoil

Iain Cheyne wrote:

> I'm not selling my 1x any time soon, but this is worth a look,
> especially the demo video.
>
> http://www.inventist.com/products/aquaskipper.html

Imagine how much more pleasant, not to mention funnier, the Tideway would be
if we made coaches use those instead.

--
simonk



17 Oct 2005 16:02:47
Re: Aquaskipper - man-powered hydrofoil

I think we've just set the buoyancy argument back a few years.....



18 Oct 2005 00:02:15
liz
Re: Aquaskipper - man-powered hydrofoil

especially as it looks like it would sink if they stopped to talk to their
crews....

liz


"simonk" <simonk@privacy.invalid > wrote in message
news:0001HW.BF79C8B0002C1017F0284550@news.individual.net...
> Iain Cheyne wrote:
>
>> I'm not selling my 1x any time soon, but this is worth a look,
>> especially the demo video.
>>
>> http://www.inventist.com/products/aquaskipper.html
>
> Imagine how much more pleasant, not to mention funnier, the Tideway would
> be
> if we made coaches use those instead.
>
> --
> simonk
>




17 Oct 2005 16:26:16
Re: Aquaskipper - man-powered hydrofoil

Have a look at the flyak,

http://www.foilkayak.com/

They are hoping to produce a foil borne K1 that will be quicker
than and 8+.

Tim W

liz (nospam) wrote:
> especially as it looks like it would sink if they stopped to talk to their
> crews....
>
> liz
>
>
> "simonk" <simonk@privacy.invalid> wrote in message
> news:0001HW.BF79C8B0002C1017F0284550@news.individual.net...
> > Iain Cheyne wrote:
> >
> >> I'm not selling my 1x any time soon, but this is worth a look,
> >> especially the demo video.
> >>
> >> http://www.inventist.com/products/aquaskipper.html
> >
> > Imagine how much more pleasant, not to mention funnier, the Tideway would
> > be
> > if we made coaches use those instead.
> >
> > --
> > simonk
> >



17 Oct 2005 16:33:09
Mike Sullivan
Re: Aquaskipper - man-powered hydrofoil


<tjw@chw.net.au > wrote in message
news:1129591576.747785.164740@g47g2000cwa.googlegroups.com...
> Have a look at the flyak,
>
> http://www.foilkayak.com/
>
> They are hoping to produce a foil borne K1 that will be quicker
> than and 8+.

NOW I know why I've been learning to paddle.

That looks insane. but it says you need a base fitness
and speed, I'd venture to guess I'm going to fall
below that threshold... :^(

Mike




17 Oct 2005 18:35:16
bobmcmillen11@comcast.net
Re: Aquaskipper - man-powered hydrofoil

If it's a serious challenge, I'm sure some foils could be fitted to an
8+ for some real speed.

Bob McMillen



17 Oct 2005 21:44:25
Mike Sullivan
Re: Aquaskipper - man-powered hydrofoil


<bobmcmillen11@comcast.net > wrote in message
news:1129599316.067464.170950@g44g2000cwa.googlegroups.com...
> If it's a serious challenge, I'm sure some foils could be fitted to an
> 8+ for some real speed.

Perhaps. Do you think it can surpass the decavitator's speed of 18+ knots
(21 mph)?

That was a cycling hydrofoil at MIT. totally cool! I'm sure the record's
been broken since then but I can't find it.




18 Oct 2005 00:43:26
Arne van Eupen
Re: Aquaskipper - man-powered hydrofoil

Naturally, already an established training tool for the Dutch M8+

http://www.nlroei.nl/Fotoboek-display-43514.html



18 Oct 2005 10:23:36
mislav
Re: Aquaskipper - man-powered hydrofoil


"Mike Sullivan" <sul@SNIPslac.stanford.edu > wrote in message
news:dj1ujb$lng$1@news.Stanford.EDU...
>
> <bobmcmillen11@comcast.net> wrote in message
> news:1129599316.067464.170950@g44g2000cwa.googlegroups.com...
>> If it's a serious challenge, I'm sure some foils could be fitted to an
>> 8+ for some real speed.
>
> Perhaps. Do you think it can surpass the decavitator's speed of 18+ knots
> (21 mph)?

Probably, but I believe DuPont's prize for 20 knots goes to one-man powered
HPV only. I think Decavitator is still the fastest HPV on water.




18 Oct 2005 18:08:09
Re: Aquaskipper - man-powered hydrofoil


mislav wrote:
> "Mike Sullivan" <sul@SNIPslac.stanford.edu> wrote in message
> news:dj1ujb$lng$1@news.Stanford.EDU...
> >
> > <bobmcmillen11@comcast.net> wrote in message
> > news:1129599316.067464.170950@g44g2000cwa.googlegroups.com...
> >> If it's a serious challenge, I'm sure some foils could be fitted to an
> >> 8+ for some real speed.
> >
> > Perhaps. Do you think it can surpass the decavitator's speed of 18+ knots
> > (21 mph)?
>
> Probably, but I believe DuPont's prize for 20 knots goes to one-man powered
> HPV only. I think Decavitator is still the fastest HPV on water.

Yes, I believe the Decavitator is the current record holder for the
fastest
human powered water vehicle. However Decavitator (and most water
HPVS)would appear to have stronger links to cycling than rowing or
kayaking as a sport.

The beauty of the Flyak is it takes a tradition boat/sport and adds a
considerable injection of speed. It will be interesting to see what the

foilborne K1 can achieve and wether it will scale to the K2 and K4.

I don't think we will see a foilborne 8+ any time soon but a 2x or 4x
on foils might be a possibilty.

Tim W



19 Oct 2005 13:41:39
Carl Douglas
Re: Aquaskipper - man-powered hydrofoil

tjw@chw.net.au writes
>
>mislav wrote:
>> "Mike Sullivan" <sul@SNIPslac.stanford.edu> wrote in message
>> news:dj1ujb$lng$1@news.Stanford.EDU...
>> >
>> > <bobmcmillen11@comcast.net> wrote in message
>> > news:1129599316.067464.170950@g44g2000cwa.googlegroups.com...
>> >> If it's a serious challenge, I'm sure some foils could be fitted to an
>> >> 8+ for some real speed.
>> >
>> > Perhaps. Do you think it can surpass the decavitator's speed of 18+ knots
>> > (21 mph)?
>>
>> Probably, but I believe DuPont's prize for 20 knots goes to one-man powered
>> HPV only. I think Decavitator is still the fastest HPV on water.
>
>Yes, I believe the Decavitator is the current record holder for the
>fastest
>human powered water vehicle. However Decavitator (and most water
>HPVS)would appear to have stronger links to cycling than rowing or
>kayaking as a sport.
>
>The beauty of the Flyak is it takes a tradition boat/sport and adds a
>considerable injection of speed. It will be interesting to see what the
>
>foilborne K1 can achieve and wether it will scale to the K2 and K4.
>
>I don't think we will see a foilborne 8+ any time soon but a 2x or 4x
>on foils might be a possibilty.
>
>Tim W
>

As you probably know, Tim, the foilborne 1x was done many years ago at
Marlow, UK, under the irresistible urging of James Grogono (he of
Jacob's Ladder, the kite-powered sailing catamaran).

With rowing there is a bit of a problem of rig height as you rise onto
the foils, & quite a problem of porpoising due to variation of lift
through the stroke cycle caused by the cyclic velocity variation.
Doubtless it could all be tidied up in various interesting & ingenious
ways, but you'd still have to handle duckweed & other waterborne enemies
of maintaining a high lift-to-drag ratio with a low power input.

Cheers -
Carl
--
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JY, UK
Email: carl@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)



19 Oct 2005 08:35:36
Re: Aquaskipper - man-powered hydrofoil

Nice celebration going on, but a strange Mix for the M8+. [;o)

- Paul Smith



19 Oct 2005 17:13:01
Re: Aquaskipper - man-powered hydrofoil


Carl Douglas wrote:
> tjw@chw.net.au writes
> >
> >mislav wrote:
> >> "Mike Sullivan" <sul@SNIPslac.stanford.edu> wrote in message
> >> news:dj1ujb$lng$1@news.Stanford.EDU...
> >> >
> >> > <bobmcmillen11@comcast.net> wrote in message
> >> > news:1129599316.067464.170950@g44g2000cwa.googlegroups.com...
> >> >> If it's a serious challenge, I'm sure some foils could be fitted to an
> >> >> 8+ for some real speed.
> >> >
> >> > Perhaps. Do you think it can surpass the decavitator's speed of 18+ knots
> >> > (21 mph)?
> >>
> >> Probably, but I believe DuPont's prize for 20 knots goes to one-man powered
> >> HPV only. I think Decavitator is still the fastest HPV on water.
> >
> >Yes, I believe the Decavitator is the current record holder for the
> >fastest
> >human powered water vehicle. However Decavitator (and most water
> >HPVS)would appear to have stronger links to cycling than rowing or
> >kayaking as a sport.
> >
> >The beauty of the Flyak is it takes a tradition boat/sport and adds a
> >considerable injection of speed. It will be interesting to see what the
> >
> >foilborne K1 can achieve and wether it will scale to the K2 and K4.
> >
> >I don't think we will see a foilborne 8+ any time soon but a 2x or 4x
> >on foils might be a possibilty.
> >
> >Tim W
> >
>
> As you probably know, Tim, the foilborne 1x was done many years ago at
> Marlow, UK, under the irresistible urging of James Grogono (he of
> Jacob's Ladder, the kite-powered sailing catamaran).
>
> With rowing there is a bit of a problem of rig height as you rise onto
> the foils, & quite a problem of porpoising due to variation of lift
> through the stroke cycle caused by the cyclic velocity variation.
> Doubtless it could all be tidied up in various interesting & ingenious
> ways, but you'd still have to handle duckweed & other waterborne enemies
> of maintaining a high lift-to-drag ratio with a low power input.
>
> Cheers -
> Carl
> --
> Carl Douglas Racing Shells -
> Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
> Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JY, UK
> Email: carl@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
> URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)

Hello Carl, yes I think I've seen this boat. It was unusual (apart from
the foils) in that it appeared to have a fair bit alloy in the frame
and
the skin was alloy too. (If I have the right boat.) I've also seen the
foil equipped Glyn Locke that was developed for the 1976 Olympics.

Having seen these boats and read of some of the difficulties they
encountered
I thought a double or quad might be a better option. More power for
take off
and a typically high stroke rate to reduce speed fluctuation and once
foil borne one of the crew could focus on the steering as the boat zips
down the course at about 30kmh. To a lay person slidding riggers look
attractive to minimise the porposing but the may make the whole project
too complicated.

Tim W



19 Oct 2005 18:24:00
Re: Aquaskipper - man-powered hydrofoil

>From what I can see on the Flyak site they hope to be quicker than
an 8+ over 2000m with their current line of developement of hulls
and foils. To be quicker than the Decavitator they suggest they
will need a new hull form and revised foils.

Tim W



20 Oct 2005 13:12:24
Carl Douglas
Re: Aquaskipper - man-powered hydrofoil

tjw@chw.net.au writes
>
>Hello Carl, yes I think I've seen this boat. It was unusual (apart from
>the foils) in that it appeared to have a fair bit alloy in the frame
>and
>the skin was alloy too. (If I have the right boat.) I've also seen the
>foil equipped Glyn Locke that was developed for the 1976 Olympics.
>
>Having seen these boats and read of some of the difficulties they
>encountered
>I thought a double or quad might be a better option. More power for
>take off
>and a typically high stroke rate to reduce speed fluctuation and once
>foil borne one of the crew could focus on the steering as the boat zips
>down the course at about 30kmh. To a lay person slidding riggers look
>attractive to minimise the porposing but the may make the whole project
>too complicated.
>

I think that boat was one of Don Ellis's stretch-formed aluminium jobs.
IIRC the bow ran on a small spoon-stabilised foil (the spoon ran on the
surface to adjust foil incidence). There was an article about that boat
in the Rowing magazine, the independent predecessor of the soon-to-die
Regatta mag - anyone got a copy that article?

Maybe the way to handle foiling for rowing is to use a much more
adjustable & responsive system. The first hurdle with fixed foils is
that you must overcome both hull & foil drag to get enough velocity for
useful lift. The second is that foil lift is so sensitive to velocity.
The third is that a you lift your hands have to lift about 50% of that
rise to keep your blades immersed. A kayak runs at much more constant
speed so may have fewer porpoising problems, but has to deal with a
maybe more severe height issue

Maybe the foils can be lowered progressively into the water as speed
builds up? With active ride-height servo controls to alter angle of
attack or adjust flaps you might keep the hull just kissing the water
despite velocity fluctuations, & I suspect any porpoising due to CG
movements could be ironed out similarly.

Cheers -
Carl
--
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JY, UK
Email: carl@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)



20 Oct 2005 13:32:39
Douglas MacFarlane
Re: Aquaskipper - man-powered hydrofoil

In article <dpBVaXBom4VDFwfJ@rowing-cdrs.demon.co.uk >,
Carl@carldouglas.co.uk says...
>
>
>tjw@chw.net.au writes
>>
>>Hello Carl, yes I think I've seen this boat. It was unusual (apart from
>>the foils) in that it appeared to have a fair bit alloy in the frame
>>and
>>the skin was alloy too. (If I have the right boat.) I've also seen the
>>foil equipped Glyn Locke that was developed for the 1976 Olympics.
>>
>>Having seen these boats and read of some of the difficulties they
>>encountered
>>I thought a double or quad might be a better option. More power for
>>take off
>>and a typically high stroke rate to reduce speed fluctuation and once
>>foil borne one of the crew could focus on the steering as the boat zips
>>down the course at about 30kmh. To a lay person slidding riggers look
>>attractive to minimise the porposing but the may make the whole project
>>too complicated.
>>
>
>I think that boat was one of Don Ellis's stretch-formed aluminium jobs.
>IIRC the bow ran on a small spoon-stabilised foil (the spoon ran on the
>surface to adjust foil incidence). There was an article about that boat
>in the Rowing magazine, the independent predecessor of the soon-to-die
>Regatta mag - anyone got a copy that article?
>
>Maybe the way to handle foiling for rowing is to use a much more
>adjustable & responsive system. The first hurdle with fixed foils is
>that you must overcome both hull & foil drag to get enough velocity for
>useful lift. The second is that foil lift is so sensitive to velocity.
>The third is that a you lift your hands have to lift about 50% of that
>rise to keep your blades immersed. A kayak runs at much more constant
>speed so may have fewer porpoising problems, but has to deal with a
>maybe more severe height issue
>
>Maybe the foils can be lowered progressively into the water as speed
>builds up? With active ride-height servo controls to alter angle of
>attack or adjust flaps you might keep the hull just kissing the water
>despite velocity fluctuations, & I suspect any porpoising due to CG
>movements could be ironed out similarly.

Would a wider shallower hull be of any use here? It might be harder to get
up to speed, but less lift would be needed to get the hull clear of the
water.

Douglas

>
>Cheers -
>Carl
>--
>Carl Douglas Racing Shells -
> Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
>Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JY, UK
>Email: carl@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
>URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)
>



20 Oct 2005 16:21:41
mislav
Re: Aquaskipper - man-powered hydrofoil

"Douglas MacFarlane" <dkm@dcs.gla.ac.uk > wrote in message
news:dj82p8$2fj$1@singer.cent.gla.ac.uk...
> Would a wider shallower hull be of any use here? It might be harder to get
> up to speed, but less lift would be needed to get the hull clear of the
> water.

The lift force required to lift the boat depends on the weight of the boat,
not on the draft. Less time might be required to lift the shallow hull than
the deep one, but if the weights are the same so is the lift force required.

Still a positive effect of a shallow hull might be that the vertical
distance the boat is lifted will be smaller, therefore shorter foil struts
could be used meaning less drag from the foil system. However once foilborn
the struts will be mostly out of water anyway so this small gain will
probably not compensate for the additional drag of a shallow hull.




20 Oct 2005 16:55:53
mislav
Re: Aquaskipper - man-powered hydrofoil


"Carl Douglas" <Carl@carldouglas.co.uk > wrote in message
news:dpBVaXBom4VDFwfJ@rowing-cdrs.demon.co.uk...
> tjw@chw.net.au writes
>>
> I think that boat was one of Don Ellis's stretch-formed aluminium jobs.
> IIRC the bow ran on a small spoon-stabilised foil (the spoon ran on the
> surface to adjust foil incidence). There was an article about that boat
> in the Rowing magazine, the independent predecessor of the soon-to-die
> Regatta mag - anyone got a copy that article?

Carl, my understanding of the Grogono experiment is that the drag produced
by the foils was even bigger than the drag of the boat without them. That
would imply that once foilborn the boat was still slower than the ordinary
shell. Is that true? Have you actually seen the boat?




20 Oct 2005 16:39:16
Carl Douglas
Re: Aquaskipper - man-powered hydrofoil

mislav <mislav.matacic@alfakompjuter.hr > writes
>
>"Carl Douglas" <Carl@carldouglas.co.uk> wrote in
>> tjw@chw.net.au writes
>>>
>> I think that boat was one of Don Ellis's stretch-formed aluminium jobs.
>> IIRC the bow ran on a small spoon-stabilised foil (the spoon ran on the
>> surface to adjust foil incidence). There was an article about that boat
>> in the Rowing magazine, the independent predecessor of the soon-to-die
>> Regatta mag - anyone got a copy that article?
>
>Carl, my understanding of the Grogono experiment is that the drag produced
>by the foils was even bigger than the drag of the boat without them. That
>would imply that once foilborn the boat was still slower than the ordinary
>shell. Is that true? Have you actually seen the boat?
>
>

I wish I knew, Mislav. No, I never saw the boat. But I did briefly
discuss it with James while we were building the last GBR C-Class
challenger. He seemed happy to have had a bit of fun doing it & to
leave it in the past. And we had lots of more interesting stuff to
discuss at that time.

Cheers -
Carl
--
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JY, UK
Email: carl@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)



21 Oct 2005 14:17:35
mislav
Re: Aquaskipper - man-powered hydrofoil


"Carl Douglas" <Carl@carldouglas.co.uk > wrote in message
news:drC1qvFko7VDFwvK@rowing-cdrs.demon.co.uk...
> I wish I knew, Mislav. No, I never saw the boat. But I did briefly
> discuss it with James while we were building the last GBR C-Class
> challenger. He seemed happy to have had a bit of fun doing it & to leave
> it in the past. And we had lots of more interesting stuff to discuss at
> that time.

From New Scientist Magazine:
"Human-powered hydrofoils have come a long way since James Grogono, an
English physician, added hydrofoils to a rowing shell in 1975. Grogono just
managed to row hard enough to lift the shell out of the water for a few
strokes. "

It appears that James Grogono wrote a book "Icarus, the Boat that Flies",
describing this and other (sailing) hydrofoil experience. More can be found
here:
http://humanpower.ligfiets.net/Human_Power/FullText/22-v7n1-1988.pdf