Why No Active Stabilization On Ocean Foiling?

[zstine]

Over 50 years ago the Navy started flying active hydrofoil boats which were able to stay above 15ft waves without slowing. Now we are starting to see some ocean foiling Trimarans and semi foiling monos, but none with active stabilization. Even the most advanced boats, Gitana 17 for example, still use surface piercing J foils.

It seems to me (and apparently the Navy) that if you want to foil in the ocean, riding above the waves on a somewhat even keel using active control is paramount. Yet all ocean foilers today ride along the surface with passive controls, which constantly leads to crashing into waves. Active control is fairly simple with today's tech...

What am I missing? if a 30kg moth can have active control, certainly an 80ft racing trimaran can. Heck, an iPhone has nearly all the capabilities you need to control flight. What's stopping the boat builders?

[longjonsilver]

Sailors are some of the biggest luddites i have ever seen. David Keiper built a foiling trimaran back in the early 70's and voyaged all over the Pacific, proving the concept, but no one followed in his footsteps for 30 years. Why? Dunno.
jon

[donradcliffe]

If the active stabilization on a Moth goes awry, its not a disaster.

[tkeithlu]

Hit one rock, and the Navy is singularly talented at hitting things, and you are in deep doo-doo. Better to solve the problem with sharp bows and seasick pills.

[caffel]

Judging from what we see of the Americas cup boats, I'd say that active stabilization is in use now. The nature of it will be a secret for obvious reasons, but the key vendors are surely learning at a high rate.
In some classes, this could be looked at as an autopilot, though.

[stormalong]

Sailors are wary of electrical/mechanical systems that run long hours and draw lots of power. I wouldn't call them Luddites.

America's cup boats go sailing for a few hours and have full support staffs with unlimited budgets. Cruising sailors sail for weeks and travel far beyond normal supply sources.

[clakiep]

I do think there is a rule for racing that no outside energy - including stored one like fuel - maybe used. So the constant energy required from active foils must be taken out of wind or waterflow...or the muscles of the crew. Shall we see in the future racing boats with large crews, and most of them working on pedals and handels to generate electricity, to enable the function of hydraulic, electric and electronic devices ? Visible on deck or better hidden inside ?

Capt. Claus - ocean tramp of the eighties

[PaulvR]

Longjonsilver: Astronomical signals and cellular codes

One is sent in an instance with intent, the other evolved over billions of years, mindless death and adaptation over eons.

Apples and Bricks..

I found the footnote a tad trolling for a response, so I obliged.

[pyroray]

I would think the limitations set by the rules, which seem to be very complicated and very slow to change, will allow such modifications as they become acceptable norm by those involved in the industry. I for one would disapprove.
And there is something to be said about natural sailing being the harnessing of what nature has given us, harnessing her forces, using ones brain and brawn. Sailing is the act of harnessing the wind, with machinery controlled by man. Other controls are helpful but takes man out of the equation.

[zstine]

Originally Posted by caffel

Judging from what we see of the Americas cup boats, I'd say that active stabilization is in use now. The nature of it will be a secret for obvious reasons, but the key vendors are surely learning at a high rate.
In some classes, this could be looked at as an autopilot, though.

Absolutely, the AC75 uses active stabilization, but it is no secret. There are engineering papers 50 years old that describe active stability control. It is relatively simple to deal with the 6 degrees of freedom using a feedback loop.

Now the secret of the AC75 is how to go 0.2 knot faster!

[pyroray]

I would think the limitations set by the rules, which seem to be very complicated and very slow to change, will allow such modifications as they become acceptable norm by those involved in the industry. I for one would disapprove.
And there is something to be said about natural sailing being the harnessing of what nature has given us, harnessing her forces, using ones brain and brawn. Sailing is the act of harnessing the wind, with machinery controlled by man. Other controls are helpful but takes man out of the equation.

[zstine]

Originally Posted by clakiep

I do think there is a rule for racing that no outside energy - including stored one like fuel - maybe used. So the constant energy required from active foils must be taken out of wind or waterflow...or the muscles of the crew. Shall we see in the future racing boats with large crews, and most of them working on pedals and handels to generate electricity, to enable the function of hydraulic, electric and electronic devices ? Visible on deck or better hidden inside ?

Capt. Claus - ocean tramp of the eighties

Depends on the class. The Volvo ocean race boats ran a generator to power the hydraulics to cant their keels... so that's certainly using outside power.


The IMOCA boats in the vendee globe now are using solar/hydro to do the job of keel canting, autopilot and running gobs of other electronics. An active stabilization system need not use much power. Dinghies foil with active stabilization (wands) which use no power at all. And even if you use electric motors, if the foils are balanced (pivot axis at center or lift) the forces to move them are very small. It should be able to be done with no more power than a typical autopilot on the rudder.

[zstine]

Originally Posted by pyroray

I would think the limitations set by the rules, which seem to be very complicated and very slow to change, will allow such modifications as they become acceptable norm by those involved in the industry. I for one would disapprove.
And there is something to be said about natural sailing being the harnessing of what nature has given us, harnessing her forces, using ones brain and brawn. Sailing is the act of harnessing the wind, with machinery controlled by man. Other controls are helpful but takes man out of the equation.

So you don't think ocean race boats should use autopilots? That would make solo sailing/racing practically impossible.

Why is using the forces of water/solar and your brain to make an autopilot in the vertical direction on a wing any different than an autopilot on your rudder?
Are there rules that govern over-all speed records (not racing classes)? Do you know where to find them?

Foiling boats have been around for decades... yeah.. slow to change is a huge understatement! Its like not allowing down-force wings on an F1 race car!

[valhalla360]

Originally Posted by pyroray

I would think the limitations set by the rules, which seem to be very complicated and very slow to change, will allow such modifications as they become acceptable norm by those involved in the industry. I for one would disapprove.
And there is something to be said about natural sailing being the harnessing of what nature has given us, harnessing her forces, using ones brain and brawn. Sailing is the act of harnessing the wind, with machinery controlled by man. Other controls are helpful but takes man out of the equation.

Kind of proves the luddite comment.

To the old salts on square riggers, all the fancy rigging on a 50yr old full keeler is spaceship stuff they would never trust. I mean seriously, mechanical winches with gears when you can just line up 10 guys and heave on the lines while singing a sea shanty to get the guys in sync. We won't even get into that belching mechanical contraption that you use to get into a berth.

[zstine]

Originally Posted by longjonsilver

Sailors are some of the biggest luddites i have ever seen. David Keiper built a foiling trimaran back in the early 70's and voyaged all over the Pacific, proving the concept, but no one followed in his footsteps for 30 years. Why? Dunno.
jon

Exactly! We haven't gotten much farther with foiling sailboats than the Williwaw in nearly 50 years. If racing 'rules' are the main driver holding back development... its time to break the rules!