Commercial Fishing Sailboat

[Kanfish]

I can only smile at the idea of Sky / Kite sails flying high off a large ship.
All the photos are taken in ' Perfect ' conditions that I have seen and showing them working at their best when the reality is that as in Murphy,s law. If it can happen it will.

Those of you that will have sailed / raced small yachts using spinnakers will know that wind direction can change / drop in strength and quick reactions are required. A spinnaker under the bow of a small yacht is a force to be reckoned with when trying to clear it, right?

The picture of a kite sail suddenly dropping to touch the sea surface, the then loose control line then wrapped around the propeller as the vessel runs over it would do so much damage and disable the vessel I can see so clearly that it would not bear consideration.

I would think too the number of ' Ships Officers ' that would have any experience enough to use one of these effectively would be very small etc.

So good luck with these.

Cheers

[BATAAN]

Here's a boat for sale today.
http://cgi.ebay.com/ebaymotors/48-st...ZOtherQ5fBoats

[BATAAN]

Originally Posted by Kanfish

I can only smile at the idea of Sky / Kite sails flying high off a large ship.
All the photos are taken in ' Perfect ' conditions that I have seen and showing them working at their best when the reality is that as in Murphy,s law. If it can happen it will.

Those of you that will have sailed / raced small yachts using spinnakers will know that wind direction can change / drop in strength and quick reactions are required. A spinnaker under the bow of a small yacht is a force to be reckoned with when trying to clear it, right?

The picture of a kite sail suddenly dropping to touch the sea surface, the then loose control line then wrapped around the propeller as the vessel runs over it would do so much damage and disable the vessel I can see so clearly that it would not bear consideration.

I would think too the number of ' Ships Officers ' that would have any experience enough to use one of these effectively would be very small etc.

So good luck with these.

Cheers

So so true, and I'm sure a dozen more disasters-in-waiting. Traditional rigs were worked out to give the most return for the least investment, and also danger. They may be crude, heavy and inefficient but they work night and day, storm and calm on the real ocean and come from a Darwinian development process that cannot be duplicated on paper because it involves many generations of survivors and the real ocean in all its moods combined with human economics.

[Cattledog]

whose hull is this?

[brian eiland]

Originally Posted by BATAAN

Here's a boat for sale today.
http://cgi.ebay.com/ebaymotors/48-st...ZOtherQ5fBoats

You have a few vessels mixed together there in that spread?

[brian eiland]

I believe if you look back thru this subject thread (beginning with posting #6) you will find that MickT does NOT intend to fish under sail...only use sails as the ultimate range propellant, or fuel extender, or enjoyment aspect.

...so in that case an auxillary kite propulsion system could will work.

[BATAAN]

Originally Posted by brian eiland

You have a few vessels mixed together there in that spread?

No, it's the same boat under her original designed rig, and as modified presently.

Originally Posted by Kanfish

I can only smile at the idea of Sky / Kite sails flying high off a large ship.
All the photos are taken in ' Perfect ' conditions that I have seen and showing them working at their best when the reality is that as in Murphy,s law. If it can happen it will.

Those of you that will have sailed / raced small yachts using spinnakers will know that wind direction can change / drop in strength and quick reactions are required. A spinnaker under the bow of a small yacht is a force to be reckoned with when trying to clear it, right?

The picture of a kite sail suddenly dropping to touch the sea surface, the then loose control line then wrapped around the propeller as the vessel runs over it would do so much damage and disable the vessel I can see so clearly that it would not bear consideration.

I would think too the number of ' Ships Officers ' that would have any experience enough to use one of these effectively would be very small etc.

So good luck with these.

Cheers

Well, thats one opinion, others may have a different. The shipping companies operating the system at present, are quite satisfied with the results. And they are not the new boys on the block, they know what they are doing.

The theoretical scenario you describe above, is technically not possible. You should better gain some knowledge on that topic before making comments.

Apart from the fact, that the system is not available in the size required for a vessel the OP needs, I would recommend it, it is a proven, and reliable propulsion, meanwhile.

Regards
Richard

[Cattledog]

Another thing to remember about Kites is, you have to bring them down at night or it is a fouled prop...

Not practical.

My father motorsailed / trolled and longlined with the main up - but mainly to stabilize the boat. Then on the run back in, if and only if wind was totally favorable would he motorsail. Its two knots for free.

Fuel savings vs sail maintainence - well, his next boat was power only.

Revisit this when diesel is $10 / gallon.

Originally Posted by Cattledog

Another thing to remember about Kites is, you have to bring them down at night or it is a fouled prop...

Not practical.

And not true either!

As I said before, get familiar with the system, then make comments!

[Cattledog]

OK now... You win as you obviously have a great deal of real time experience using this type of product. Whereas, I whom flew kites competitively throughout the world, fly paragliders now and have probably more.... Oh, just forget it, it's not worth it.

When Evergreen or Maersk converts their entire fleet to this technology, then you may have something to dream about for a small boat. But until then... lol

[brian eiland]

Originally Posted by Cattledog

...Revisit this when diesel is $10 / gallon.

How far are we away from this reality, do you think? And I'm asking this question in a 'worldwide sense' because our fuel prices in the USA have been relatively low in the scheme of things.

...we should be working very diligently on alternatives...now, not later

You might find this video film and discussion interesting:
CRUDE oil that is.

[Cattledog]

The technology for this exists now... You can stack kites in chains to get desired amounts of lift. Procure 3 (two man size) large paragliders and rig them as a stack and you can pull your 50 to 60 ft displacement hull at hull speed quite easily in 20 knots of wind. Hook them to a deck winch for retrieval and you have your own SKYSAIL system for about $15,000. It is really that simple.

Problems:
1. Changes in wind speed
2. Changes in wind direction
3. Need to change course of vessel
4. Night time visibility of kite system – this is a big one – there are LED lighting systems but my guess is that the systems are pulled down at night
5. Wear – the fabrics currently used will chafe in constant use due to salt accumulation – my guess is that for every 1000 hours of deployment you need new canopies. This however, is nothing but a guess.

Assuming oil costs accelerate – we will see $10 / gallon fuel in 30 years. However, bunker oil that a commercial freighter burns is around $1.30 per gallon now so $10 is a very long way off for them.

But for giggles, let’s assume $3 per gallon now and per Skysail, you can get 10 percent savings in fuel costs. So we have 30 cents on a burn rate of 10 gallons per hour = 3 dollars per hour of savings. To pay for the system I have described, you need to operate the system for 5000 hours. Assuming 12 hours per day of operational capability you now have 2500 days to get a return on investment or 7 years before you see penny one of profit from the system. The canopies and lines won’t last that long so the system may never produce a return on your investment.

I’m just thinking out loud here…

[brian eiland]

I guessed the jump to $100 dollars per barrel to within a day. I will guess that 10/per gallon will be reached in less than 5 years...probably more like 3 years

[Cattledog]

not likely, but then your guess is as good as any...