First of all, my earlier post was more or less a brief summary of a few pages in my Textbook about Hydrodynamics on foils and ships (I'm a student at the Department of Marine Technology here in Norway, civ.ing degree), so that text is not false.

Erice, I wouldn't be too suprised of your top speed not being higher. Or, put in other words, 16+ knots on a Nacra 5.2 is fast! My dad and I sail a Taipan 5.7, which really is a fast cat (rated faster than F18s for instance), and we have never logged a better top speed than 19.7 knots. We are both certain that that particular blast isn't our fastest ever, so we consider our top speed as being just above 20 knots. This was done when a big puff(I'm guessing around 10 m/s) hit the boat, me out on the trap, dad inside on the helm, no spi up. No doubt, a better and more experienced crew could probably yank a couple of knots more out of the boat, but not a whole lot.

As for the 18ft skiffs, according to Frank Beathwait those monsters topped out at more than 30 knots in big winds and sailing with small rigs. There's a spectacular picture of a skiff screaming along in crazy conditions in his book. Around a course a Tornado would outsail them, as for sheer top speed however, I think the skiffs are way faster.

I assume you mean the Hurricane 6.5? What a monster!

I've seen them, sailed around with them, but never sailed one!

A quick google for "Hurricane 6.5 catamaran" came up with:

this

We even have a gallery on Catsailor here

This one is Reg White helming the rack boat:



This one is Rob White helming the ladder boat:



Here is a pic of a yellow one:



Some old stuff in german I think

I think he was referring to the Hardcore Hurricane, which was apparently a 16' boat (listed here), but there may be a connection to the Hurricane 6.5... Here's an article that indicates that the Hurricane 6.5 was aka the Roake 21 (and links to those photos here at catsailor). I guess this is the one Mary was referring to.

Edit: Indeed, one of the other images confirms this connection...

http://www.catsailor.com/gallery/displayimage.php?album=81&pos=8

Wouter,

My argument is not "smoke and mirrors", I am merely pointing out that "Mediatis-Region Aquitane" is a very succesful boat, contrary to what you seem to be trying to indicate in your post.

Regardless of the fact that there are three trimarans that have since beaten Yves Parlier's 24 hr solo record, I still can't see how you can maintain that this boat is not a winner, unless you are so desperate to never admit that you have made a stupid statement.

For people who are not familiar with this 60ft catamaran and who may take Wouter's statement at face value:-

As far as the 24 hr record is concerned, the boat is the fastest solo catmaran ever, it is the fastest fully crewed catamaran under 100ft and has proved itself to be up there with the best of the trimarans regardless of size. I will leave it to each individual to decide wether that makes it a "winner" or not.

Gareth

Ok, much more important!!!

What... is the Airspeed Velocity of an Unladen Swallow?

Well the Laden Swallow airspeed can be calculated by using the pi r round theory, thus the Unladen Swallow is calculated by subtracting the square root of the volume of recently ingested food times 1.23174 divided by its inverse factor to get EXACTLY what we think it will acheive (optimally). <img src="http://www.catsailor.com/forums/images/graemlins/smirk.gif" alt="" />

Of course this assumes the bird hasn't had sex in a while which could make it much faster given its looking for a mate!

JMO,

Clayton
BS Engineer (and we know what the BS stands for)

African or European?

Is that one of those "Like you or love you....swallow vs spit" arguements?
Airspeed of her spit of an unladen swallow? Sorry for the triple XXX but Andrew brought it up. <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" />

Dave, swallow (the bird, not the act of)



and now for something completely different

and now for a different, something completely different

The Hardcore 16 was the Hurricane 500, but I'm not sure if it received the hull(skeg enlargement and reduced rocker) and rig changes of the 500. Great boat but too much volume low down for singlehanding in light winds. It was not a 'dog' as often quoted but did not have enough 'Bite' in the water without either a crew of two to load up the leeward hull or enough wind to generate lift from the skegs . Using a hurricane sport jib I had to slow down once to let the safety boat catch up. I had previously clocked the safety boat at 25.8 mph on gps and my hurricane 5.9 at 22.9 mph around the bouys. Pity it was not built with daggers or given a proper rig. John Pierce apparently tried to buy the moulds, but white formula wouldn't sell. So JP made the stealth.

Cheshirecatman

We must be talking about different boats entirely.

Now you are putting up a characture of my post that you can then knock down.

I never wrote that "Mediatis-Region Aquitane" was a failure. I wrote that it wasn't a winner and it is exactly that. In direct comparison with other design in its class, the forced mode displacement trimarans of the ORMA 60 rule it failed to show a clear advantage. And it is currently second in its 24 hour speed record (in all categories) to such a forced mode displacement tri.

I refer to this example as to show that by simply going to a planing design one must not expect to automatically have superior speed. There are many counter examples that argue against such a oversimplification. This includes "Mediatis-Region Aquitane".

Sory mate, you have to read more carefully.

As do we as your argument totally dependent on the fact that no other (singlehanded) true racing catamaran has been build in the 50-100ft length range. By being the only one in this length range it is indeed the fastest of IS KIND. Big deal. Of course you top the range off at 100 ft or else you have to included craft like Orange 2. That is the smoke and mirrors part my friend. Afterall we all know that the Hobie 16 is the fastest boardsless, spinnakerless and strict One Design beachcat between 16 and 16.5 foot length.

So what are trying to do here ? Taking a piss at my personally and confusing everybody else.

Wouter

I think this thread needs some Doug Lord.

Is forced mode faster than fifth mode?

Apart from the personal attacks, I think this thread has some technical merit.

I'm no expert, but doesn't a trimaran mostly operate with a planing center hull and a forced displacement outrigger at the same time? If so, that would seem to complicate matters...

I must say, this is all quite mind-boggling... 42 is looking better and better all the time, I need to enlarge my hatches so I can take my towel along when sailing. One never can tell...

I have really appreciated any sensible criticism or feedback as I have discovered several threads of thought that will help, a man who reports he was happy sailing a beach cat at 25 knots, the fact that very credible modern designs do not and while my efforts might not mean much they are efforts I appreciate help with.
I want to be clear I am not trying to create a buoy racing cat. I just want to successfully, without huge changes make my old hard chined cat do 25 knots.
I have however had interesting side results such as not losing much overall speed in any area and that the boat is well faster and much easier to helm solo than My old Nacra 14sq. So much so I sold the Nacra as it was not worth pulling the sail up on what with the TS being lighter on the beach as well.

As to where I sail in the Bay. Anywhere but mostly Te Rawhiti way.
You must have seen the Te Puna inlet which is a fabulous low chop high wind area.

By the way, to the swallow guys as the bird which flew out in front of my car yesterday, taking up residence in the grill, forced mode can reach 75 miles an hour while passing.

was he african or european?

Forget all of this theoretical BS that only about 1/4 of us can understand or care to understand. Let's see some GPS screen shots at speed. Describe the boat and conditions. Step out of the theoretical and into the real world.

Lat and Long would equal off the coast of Yemen, pretty tough shore break

How right you are! Right in the Gulf of Arden (I think thats right...)

Clayton