Sailrocket 2 set to launch

=================
Steve, it might help if you'd read the whole thread or at least the last few days worth. Paul Flados, Magnus Clark and at least one other made good arguments that the boat is not a foiler which I "mostly" agreed with. That was before I read the "Facts" section of the SailRocket website.
Specifically posts 157, 159,161,162,163,164,167,172.

 

Doug, when you say the "Facts" on the website, you mean this which you've quoted "
* Found these under "Facts" on the website
•The back of the boat will lift onto the curve of the foil at around 25 knots. The leeward float will begin to fly clear of the water over 50 knots. Only the main foil, the rudder and the ‘step’ of the forward float will be in the water at high speed.
--
•The curve of the main foil determines how high the boat rides

I agree with you on the fact that the rear is lifted out of the water by hydrofoil action of the inclined main foil, ie the longest part of it, but as Sailrockets facts point out, once beyond 25knots the curve of the foil is semi-submerged ie half in half out,controlling ride height, so at this point the long part of the main foil is also flying, and no longer contributing lift to the boat. In fact lift is the last thing they would want at this point, as the 'claw' of the foil is holding the boat down against the pull of the wing.
The front-on diagram P. Flados posted recently actually shows how similar Sailrocket is in concept to the kitesurfers, and perhaps why the kitesurfers were able to go much faster than the windsurfers, given that the forces are opposing and balance out. When I look at how much spray the kiters (and sailrocket) generate, I struggle to understand how that can be faster than a windsurfer generating much less water disturbance, but the proof is in the numbers and the windsurfers are left somewhat behind.

 

Sail Rocket

SailRocket Facts: http://www.sailrocket.com/node/292
I don't see the functional similarity to kitesurfers at all but that doesn't mean anything.
There is a "device" called "Sea something" which I saw the other day and didn't save- it uses a hydrofoil for downforce to allow the kite guy to fly along in the air.

 

I think we can all agree that vessels of the SR type are in a class of their own and should not be lumped with kiters, foilers or other types working on different principles. They are all sailing craft, so's my kayak when I use an umbrella on downwind stretches, and that's about as close as they get to each other. I have a Bruce foil which pulls down on the starboard tack when the kayak is carrying a "real" sail, but it is hardly a SailRocket.

Any contact SR may have with the water when in full flight is as much for altitude control and steering as it is for buoyancy. Actually lifting off would be a disaster: it is designed to operate as close to disaster as it can without quite arriving.

We're starting to sound like a bunch of lawyers looking for a higher court ruling to use as a precedent, but SR's success is unprecedented. Maybe this is a good time to move the task of finding an appropriate name elsewhere: perhaps the Boat Jokes thread . . .?

 

Hi Doug, from the Sailrocket 'facts' which were written before they even know exactly what the facts would actually be :
"If the main foil fails at high speed, the back of the boat will lift. The result will be that the wind will push down on the beam rather than lifting it like it did on the first boat. It must do this before the boat gets too nose down."
This is what I've been saying.

"At low speed, the boat will be predominantly steered by moving the beam and wing fore and aft by up to 3 meters. At low speed it is forward to help the boat turn away from the wind. As the boat accelerates the beam is moved aft until it is at 90 degrees to the fuselage."
They designed the boat with this in mind, but never actually operated it this way, so we shouldn't always take the facts as being altogether factual, until after the fact ..

 

The video of that thing flying over water is amazing!

 

SailRocket-Inclined rig Hydrofoil Proa.

===================
Terry, its already been named-read the description of equipment in post 179.

 

- oops, missed that, but I don't think "Inclined rig Hydrofoil Proa" is a name so much as a technical description!

 

Doug,

I am in total agreement that the main foil is a hydrofoil that provides passive altitude control for the rear.

The planing surface provided by the front pod functions a lot like the front "feeler" on the windward side of Longshot and the Trifoiler boats.

However, calling the boat a "foiler" sells it way short. Kind of like calling a SR-71 Blackbird a "jet airplane".

VSR2 is a Bernard Smith inspired, full flying, balanced primary forces, passive altitude control (planing up front, hydrofoil to the rear) Proa.

All of this terminology discussion is "just for fun" at this point given the results.

Once the dust settles, we could petition Paul Larson to see if he would go along with calling all "Bernard Smith inspired, full flying, balanced primary forces, passive altitude control" boats as "sailrocket class" boats in tribute to what they have done.

 

Sail Rocket

My submission: "Balanced Forces Hybrid Planing Foiler"
Depending on who actually filled in the form below Paul Larsen may have already spoken:

 

My nomination is “Fast Inclined Rig Proa” although some may not like the acronym FIRP, but FIRPer comes handily to mind and is nicely reminiscent of foiler.

- FIRP is also the acronym for "Funny - I'm Really Puzzled" which sums up the current understanding of SailRocket in the boating world . . .

 

I think it should just be called a Sailrocket. Boats that are designed to operate in a similar way should just be known as "sailrockets". There. Easy..

 

SailRocket

More from Africa: http://sailrocket.com/node/650 Another run today-maybe.
-----
The Magic Mile video-watch this if you haven't already-multiple camera angles:
http://www.youtube.com/watch?feature=player_embedded&v=sZVIj5TUSKE

 

Sail Rocket-going for 60+ today

from Africa: http://sailrocket.com/node/660

Paul from a post on SA today:

Hi all... well I'll burn up some of my nervous energy here for a moment. Today is building into a big day. There has been some interesting points raised that do need answering. For us it was pretty simple what we were aiming to do with this boat. Simply we were aiming to see how fast you can go using wind and water. We chose this Bernard Smith based concept for the performance it could deliver with a focus on power and stability at the edge. Of course we could make a tacking version... but practicality is not the focus. We only have to go one way over 500 meters to show some form af stability and directional control. The reason we only have to go one way as against a cars record is because we are obviously wind powered... whereas they can't have any wind 'assist. In a funny way, VSR2 is actually a very practical boat. It can be sailed with 3 people. We can have it out of the tent and rigged quicker than a Hobie 16 (mast down). It's a pretty sorted boat in that respect. If we were to have started with a daysailor version... not many people would have understood the possibilities of the concept. If, on the other hand, we go out and do it now, after setting an outright world record, then people will pay a lot more attention. The concept is proven beyond doubt. Once again, our focus was getting the record and we believed that this was the best means of stability and control available. Bernard Smiths concepts are now firmly on everyones radar. Full credit to a very deserved man. As another note... to be fair, I believe that the kite and wind surfers get driven to the top of the course after a run in Luderitz. I have no problem with that. I know that they too could technically sail back up as we too could technically build a tacking version of VSR2 (which would look super cool with twin inward inclined rigs and a simple vertical central board). The outright record is simple and pure. It allows you to focus on pushing the limits of wind and water. What people take from these newly illuminated limits will be of great interest to us. It would be interesting to still have a record which requires you to sail in both directions... but I'm afraid this would only exaggerate the advantages of a Bernard Smith style boat which does its best on a beam reach. Our next boat will be a bit more practical... and you will know without doubt where we are coming from. A lot has to happen between now and then i.e. survive today.
Cheers, Larso.
============================
Preliminary:

Ok mental speed,s!!! On the GT-31 gps 67.74 and an average 500m 65.37! Yihaaaaaaaaaa...

14:21:19 Today
========
Thats 77.9mph peak and 75.18mph average(tentative?) wow!

 

For my "And the job is (and has been since Longshot) finding a foil that will break through the cavitation barrier." in post 111, I think we can say "Job complete" and well done.