High-Speed Sailing

Vessel Name: Sailien
Vessel Make/Model: Experimental/custom
Recent Blog Posts
28 September 2013

The America’s Cup

I watched, with interest, the videos of the 34th America’s Cup. At last we have fast sailboats engaged in a competition that is fun to watch. The virtual images (such as course boundaries, distance grid lines, separation between boats, etc.) overlaid on the real images really helps to keep the race [...]

31 August 2013

100 Knots for Hydroptere?

The latest news from Hydroptere is that they have plans for a 100 knot sailboat. This was posted on 26 Aug 2013, so look for that date at this address. http://hydroptere.com/en/the-news/last-news/

17 November 2012

Aptly named Sailrocket, blasts off!

While yet to be ratified, Sailrocket posted an average speed over 500 meters of 59 knots. I will not be surprised if they increase their record into the 60 knot range during this record attempt.

02 January 2012

More drag for VSR2?

I want to start by pointing out that the whole VSR2 team has done a stellar job and has demonstrated conclusively that the forces that drive a sailboat can be aligned for roll stability without using ballast and without using any down-force. (Trifoiler achieved roll stability by using down-force, but [...]

18 December 2011

My analysis of Sailrocket

I copied a diagram of VSR2 (wing doesn’t show well) and added in the major force arrows that apply. Be aware that these arrows are not correct in terms of scale (length) and some of their locations are guesses, however I believe I’m correct enough for us to learn something about what VSR2 has been [...]

23 October 2011

60 is within reach, what’s next?

I have been watching Sailrocket’s progress with great interest and there’s no question they have a winner. I fully expect to see them reach 60kt in the near future. Sailrocket has now demonstrated what I first learned with my models and again with my full-sized prototypes, that if you get the forces [...]

Sailrocket has a winner

12 March 2011
I hope you've been checking out Sailrocket's new craft, VSR2. It is awesome! If you haven't, you can see their video at: http://www.sailinganarchy.com/article.php?get=7080
Also view their VSR2 at: http://www.sailrocket.com/

So what's my take on it? Well here goes: First off I'm happy to see that they will be moving the wing position relative to the main foil to control yaw (steering) at lower speeds. This should totally handle the yaw problems that VSR1 was having. Those of you that have been following my blog will recall that I suggested they do that in my post "This one's for Sailrocket" (12 Sept 2009), but I don't know if any of the Sailrocket team have been reading my blog or not. Note that moving the wing's position relative to the boat is the same as rotating the boat relative to the wing, just depends on which part you are sitting on.

I like that they will be using a forward rudder, it makes sense as iceboats and land yachts have been doing that for decades and high-speed sail boats are now in their speed range. Also angling the fuselage into the apparent wind to reduce drag is a good call (the craft will appear to "crab" to the lee.) I don't know if they got that from Greenbird but Richard set the tire direction off the centerline of Greenbird for the same purpose (he mentioned that to me in an email chat we had). You can watch Greenbird crab to the lee in some of the shots of his record run.

As an aside, it looks to me like Richard should have angled the tires even more than he did because the video shows the trailing edge of the wing to be on the lee side of the fuselage and it should be slightly on the windward side (about equal to the angle of attack to the apparent wind). Observe that on their web page "Design Criteria" Sailrocket's wing is positioned correctly in that respect.

I've stated before, that except for the control problems it experienced, VSR1 was capable of breaking 50 knots and the record of its time and I have every confidence that VSR2 can set a new record. I'm looking forward to it.

I wish Paul and all the crew the best of luck and "Get that record!!"

Bob
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