Onboard Video - Hydrofoil Trimaran Broomstick

Sailing my foiler Broomstick had to take a back seat to other activities in 2011, so there's very little progress to report for the year. However, my 90-year old mother in Florida sent me a GoPro Hero for a birthday gift last spring. Just for fun, I've put together a short video of clips from 3 outings last summer.

http://vimeo.com/34164014

Comments are welcomed. Just don't be too hard on me; this is my first attempt at any real video editing (other than just extracting pieces).

Doug Halsey

 

Broomstick

Doug, for me the video is stopping every few seconds and stopped for good about a third of the way thru. The earlier test version worked straight thru ok.
A question: how much wind to get on foils? How high can you point?

PS- the speed shots are out of sight! Video stopped less third time-don't know if its my machine or what......

 

She's a beauty Doug, great video. I noticed some runs had an ama on the ends of the beams and not on other runs, what is the reason for this? different conditions?
Crashes were interesting and the end of the video was great!
Thanks

ps the video worked fine for me

 

Great video and congratulations in creating something which looks great fun.

Be great to see some more shots of the craft and hear more about its design and construction.

 

Problems Viewing the Video

I'm sorry you're having these problems. Maybe posting HD video isn't the best idea ?
Here's the suggestions from Vimeo Support :

To which I would add :

It could also be that the music files that I added to the video didn't come through Vimeo's conversion process as well as the original audio. I'll try to look into this.

Doug Halsey

 

Video ran fine for me without interuption, I've found a Word document you wrote Doug on foils.org which has provided a lot more information.

 

========================
Doug, when I used your link to go to the "old" video it didn't require the password and looked like the new video-until it started running: no music and no stops whatsoever! The boat looks so good!
PS- I haven't had a problem on vimeo before......everybody else seems to be ok-don't get it-as far as I know I have up to date stuff.
----
A bit more on Broomstick: http://www.boatdesign.net/forums/mu...ng-hydrofoil-trimaran-without-amas-23293.html

 

Doug,

This was great, congratulations on getting up on foils. I know it is more common now but lots of people have had lots of trouble.

You have obviously discovered the problem with pure foils on the cross beam, little ability to get started. The amas were a good idea, I would like to see video of you starting from a dead stop. My guess is that a bigger ama would make the crashes and the start much easier.

Do you have pictures from the side? What rig are you using?

Are you willing to show the foils? I don't want to steal any ideas, but it is interesting to see what is working.

How much does the boat weigh?

Great Video. Thanks

Marc

 

More Information on Broomstick

For many viewers, this video is just a general introduction to the boat. I'm hoping to eventually put together some more informative videos to explain various aspects of designing & sailing surface-piercing foilers.

In the meantime, more information about Broomstick can be found at :

1. http://www.foils.org/gallery/071111 Broomstick_4.htm
This is a pretty long writeup for one of the International Hydrofoil Society's newsletters, written in Fall, 2007 when I was struggling just to break 20 knots.

2. http://www.boatdesign.net/forums/sailboats/foiler-design-2447-64.html#post358563
This is a more recent summary (April 2010).​

3.http://www.boatdesign.net/forums/multihulls/broomstick-breaks-25-knots-22504.html
This was posted in May,2008.​

4. http://www.boatdesign.net/forums/mu...ng-hydrofoil-trimaran-without-amas-23293.html
This was posted in July,2008.​

I'm also glad to answer questions in this thread, but I only have a limited amount of time that I afford to spend on the computer these days, so you might not get quick answers.

Thank you (everyboby) for your comments.
Doug Halsey

 

Doug(and anyone interested in more Broomstick info), I've moved the 2010 Foiler Design material(still there) to the new thread in the "Hydrodynamics and Aerodynamics" forum under Sailing Foiler Design.
http://www.boatdesign.net/forums/hy...foil-assist-full-flying-40894.html#post513022

 

Doug,

Looks like I should have researched further before making useless suggestions (putting on amas).

 

Version of Video With No Music

In case there are others still having trouble viewing the video, I have removed the password-protection feature from the earlier test version that I had previously asked Doug Lord to review & that he referred to in the above quote. This version has no music - just the boat's sounds, as originally recorded.

http://vimeo.com/32782915

Doug Halsey

 

looks like a ton of fun

 

Sailing With or Without the Amas

A couple of people have asked about this.

When I posted about "Taking Off the Training Wheels ..." back in 2008, I had only sailed without the amas once & considered it something of a stunt. Now, it's by far my preferred mode. The amas are useful for sitting at a mooring, for sailing in very light air, & for tacking & jibing, but whenever the boat has any speed at all, it's better without them.

In addition to the obvious advantages to sailing without amas (less weight & windage), I've found 2 more :

1. Less drag due to heeling in semi-foiling mode.

This requires some explanation. Being a fairly "conventional" surface-piercing foiler, Broomstick doesn't have large enough foils to fly much of the time, so it's performance when the main hull is at least partially in the water is of major concern to me. Going to windward, it's takeoff speed of 12 knots or so just isn't going to happen until the wind is up in the mid-teens. But the foils still are effective for combatting heeling. When the boat heels enough for the leeward ama to just touch the water, I can instantly feel the extra drag & sometimes it feels like the ama actually grabs the water & makes it heel more. (What I think is actually happening is that the extra drag slows the boat, causing less lift on the foil & hence less righting moment.) Without the amas, it sails to windward much more smoothly & is far easier to sail.​

2. Easier to right when turtled.

With the amas, it's impossible for me to right it. I have to remove one before my weight is enough to sink one side. Without the amas, the boat is more likely to turtle if it capsizes, but it's no real problem if it does.​

Because my amas are attached to the crossbeams with loops of bungee cord, they only take a minute or so to attach or detach. (Here, I'm referring to the 7' amas that I use when I'm sailing Broomstick as a foiler. I also have a set of 11' amas & a daggerboard that I can use for sailing as a conventional trimaran without the foils.) On a typical day, I usually attach the amas for rigging at anchor, get warmed up a bit by sailing with them attached for a while, then remove them for some more "serious" sailing. If the wind is particularly fluky, or I'm feeling more like taking it easy or writing notes, etc, sometimes I'll just leave the amas attached. But, as I said above, I very much prefer sailing without them.

Doug Halsey

 

Great stuff, Doug. Like I said before, you've got courage, a better man than I am, Gunga Din. The crashes reminded me of a certain previous boat of mine, now defunct ... but being sort of resurrected by another crazy (Mickey Knuckey) on Waiheke Island; he motored there with the broken beam and ama across the boat, a proa; quite an ordeal because it blew up to 25 knots and the hatch was lost, he baled with a paper coffee cup ... which failed.
Here's Sid - working on getting the full wing bearing correct at the moment.