From - Mon Mar 10 13:18:05 1997 Received: from beasley.cisco.com (beasley.cisco.com [171.69.2.135]) by cheerios.cisco.com (8.6.10/8.6.5) with ESMTP id MAA21727 for ; Mon, 10 Mar 1997 12:05:26 -0800 Received: from bolero.rahul.net (root@bolero.rahul.net [192.160.13.1]) by beasley.cisco.com (8.8.4-Cisco.1/CISCO.GATE.1.1) with SMTP id MAA00725 for ; Mon, 10 Mar 1997 12:05:23 -0800 (PST) Received: from waltz.rahul.net by bolero.rahul.net with SMTP id AA28144 (5.67b8/IDA-1.5 for ); Mon, 10 Mar 1997 12:05:19 -0800 From: Randy Devol Received: by waltz.rahul.net (5.67b8/jive-a2i-1.0) id AA12314; Mon, 10 Mar 1997 12:04:15 -0800 Date: Mon, 10 Mar 1997 12:04:15 -0800 Message-Id: <199703102004.AA12314@waltz.rahul.net> To: cliff.sojourner@cisco.com Subject: Blade Runnings 1 X-Mozilla-Status: 0001 Content-Length: 6682 Hi! (If you received this email, you are on the unofficial Trifoiler email list I maintain. About once per month, (or more often if the news is worthy) I try to update list members with information about the Trifoiler and what I have been doing with Blade Runner. If you do not want to me on the list, let me know.) It's winter here in the San Francisco Bay Area. I have been working on the Trifoiler (and the trailer) to make it easier to launch and recover. I have also started adding the instruments I want. I have named it Blade Runner. Thanks to Quest-7 for producing wonderful graphics. The name runs the entire length of the cockpit on both sides. The letters are 5 inches high and are the same color purple as the sails. Kewell! The trailer has new bunks with padding so that I can (almost) launch it by myself. (Thanks for the idea goes to Larry in Reno who did the same to his Trifoiler trailer.) After I get the shroud extenders installed on the guy wires, I will be able to easily launch it by myself. The most interesting addition to Blade Runner is the electric motor. It is most useful for light wind conditions where sailing a boat made to go fast has trouble going anywhere. (See Below) The motor and battery add about 80 lbs to the boat and are removable for getting back to "racing trim." Under motor alone, Blade Runner travels at about 3 knots (in forward. We did not try high speed reverse.) which gives me enough speed to have steerage. It is not really enough speed to motor to a destination very far away and the battery will not power the motor for more than about 3-4 hours. When not in use, the motor slides up on deck and out of the water. It kind of blocks the view ahead, but not completely. This motor is everything I wanted it to be (except free, less than one pound, and transparent). Race Results: Chris (my regular crew) and I took Blade Runner on a test sail with the motor and to check out the Richmond Yacht Club Small Boat Midwinters. The original thought was to race in the multihull division against Hobie 16's, Hobie 20's, and perhaps a Tornado. As it turned out, because the wind was so light, (3-5 knots) and because the large fleet favored a very maneuverable boat, we bailed. We did not start. It was fun to be out there watching 100+ well sailed small boats. There were lots of Lasers, Internation 14's, International Canoes, Moths (I think), Snipes, Bights (sp), El Toros, and others, all sailing faster than Blade Runner in those conditions. :-( Oh well. Our day will come. As an experiment, I removed the sensor off one ama and observed that the wake behind that ama became much less disturbed. I am sure that the slow performance can be improved by removing both sensors. But don't do this at home kids, unless you know you will be able to put them back before you *need* them. I considered it safe because the wind never got above 5 knots. There was No way we were going to get up on the foils. (Thanks go to Dave Culp for that suggestion.) New instrumentation: The new Trifoilers come with a compass. I added a compass too. I also added a Speedmate boat speed instrument. At first, I was sure that there was no way to have a water speed indicator that used an impeller. Once on the foils, there is no place physically large enough to mount conventional impellers; they are all about the size and shape of a juice glass (not an O.J. reference) and require a wire of some kind from the impeller to the display. The Speedmate elegantly avoids both problems. The impeller is about the diameter of a pencil and about 3 cm. long. It is designed to be pulled through the water and spin like a free-wheeling propeller. Inside the impeller is a magnet. As it spins, it generates a moving magnetic field around it. An induction coil (the size of a hockey puck) picks up the magnetic pulses and the display converts them knots or meters/sec. It also includes an odometer. Nice. (Are you listening Greg?) Assuming it passes the high speed tests, I plan to mount it on top of the mechanical display. :-) I installed the impeller behind the trailing edge of the rudder, as low in the water as the pitot tube opening for the mechanical speed display. It should be in the water at all times except during the almost-out-of- control reaches. On Blade Runner, the distance from the impeller to the pickup coil is about 25 inches. At that distance, slow speed sailing (below 2 knots) produces inaccurate results. At speeds above 2.5 knots the displayed speed corresponded very well to the perceived speed through the water (based upon wake from the amas). It also corresponded pretty well to the GPS speed if you averaged over minutes. I can't wait to get it up to speed! News flash!!!!! Joe Siudzinski, the Bay Area Multihull Association's official performance handicap setter has given Blade Runner a PHRF rating of -240. This is THE most negative number I have ever heard of. He derived the number with very little hard data and the number assumes that the entire race is spent up on the foils (which I don't expect will happen very often). The number will get adjusted each winter based upon race results. If things go well this season, I may have a more negative rating next season! (Not!) Just in case, he also gave Blade Runner a rating for races completed without getting up on the foils, but I don't remember what it was. The first YRA race will be the Vallejo Race, the last weekend in April. I have invited Greg Ketterman to join me, and he said he will if his schedule will allow it. Look for us at the finish line an hour or two after the start! Also look for me in the Delta Ditch Run, the Jazz Cup Race, the Silver Eagle, and any other reaching race. Look out Rocket 88! Look out current course records! -=O=- Randy |\ |\ Am I dating myself? | | | | | | | | No, but I *am* waiting by |\| |\| the phone for me to call! |_\__o~___|_\ o===\_/===o ~~~~~~~~~~~~~~~~~~l~~~~l~~~~l~~~~~~~~~~~~~~~~~~~~~~~~~ Blade Running P.S. F.Y.I. Wind Toys is the No. Cal. Trifoiler dealer. They are going to be at the Oakland Boat show at Jack London Square, April 20-28. They will have a Trifoiler in the water giving rides. I would like to give rides also on the 20'th and 21'st, if I am ready for the Vallejo race by then. Check them out. Their number is 800-499-7245.