I did some analysis on the ORC handicapping system in preparation for the upcoming Harvest Moon regatta, which we’ll be doing on Mike’s Olson 30. The race is a 150 mile slog down the beach to Port Aransas, from Galveston. The start of the race is exiting, with over 200 boats strung out on the starting line off the Flagship Hotel in Galveston. The race is typically a tight reach in 10 to 20 knots of wind; probably the Olson’s worst point of sail. It’s virtually un-winnable if we get a tight reach all the way to Port A. But if we get a norther on the day of the race, we could be fighting for line honors. A big norther came in last year, and a Hobie 33 was very nearly the first monohull to finish.
I’m a little unsure of the results of my analysis because I was guessing at units to use in the ORC formulas. But the spreadsheet values seem close, so I’ll assume, for now, that I got the units right. I used a 150 mile race and ran the calcs for 5 boats as if they all finished at the same time for 15 hour, 20 hour, and 25 hour races, using the ORC Performance Line Offshore calculations.
For funsies, I also did calculations on Windward Leeward, and Circular Random ORC performance numbers. It is my understanding that we will use the Performance Line Offshore for Harvest Moon.
It’s useful to compare the Olson 30 and the J105. The J105 owes the Olson 30 somewhere between 30 and 60 minutes, depending on how long the race takes and whether the J105 registers with PHRF sails or class sails. In simpler terms, the rating supposes that the J105 is somewhere between 12/secs per mile and 24/secs per mile faster than the Olson 30. In light air (light air = long race), the Olson gets less of a bonus per mile because its’ distance factor is large, relative to the J105. In heavy air (heavy air = short race) the Olson maintains its’ time advantage, again because the distance factor is large, relative to the J105. The distance factor overwhelms the calculation for long races of short duration. The time factor plays more into the equation for short races that take a long time.
All that said, we get hosed on ORC if it is upwind all the way to Port Aransas. But we knew that before we entered. The same would be true of PHRF. The Olson needs to go downwind to justify its’ rating.
What seems a little weird is the Circular Random and Windward Leeward comparisons of the J105 and the Olson30. It looks as if the J105 owes the Olson 30 much *more* time for these types of courses. I’ve raced lots of windward/leewards in the Olson, with J105s on the same course, and I can tell you with confidence that the Olson competes quite well with the J105 on a windward/leeward. It’s on the reaches that the J105 really shines, especially if they can carry their asymmetrical chute.
For all cases, it looks as if the 1D35 will owe the Olson 30 close to 3 hours, and the Beneteau 50 will owe the Olson close to 2 hours. The Beneteau 50 will probably crush us on a medium+ air tight reach.
