PHRF (Performance Handicap Racing Fleet)

PHRF yacht handicaps are established by individuals or committees, whose intent is to base them on the observed performance of existing boats, and on the anticipated performance of new boats. PHRF handicaps are expressed directly in terms of seconds per mile. This places all PHRF boats in a single numerical hierarchy, with slower boats given higher handicap numbers, and faster boats given lower, even negative, numbers. In a PHRF race, a bigger, or faster boat ‘owes’ a time allowance to a smaller, or slower boat that is quantified by the difference in their numerical handicaps in sec/mi multiplied by the course length in nautical miles. Since this is the only mathematical calculation required under PHRF, it is more a ‘system’ than it is a ‘rule’, since a ‘rule’ is commonly assumed to involve mathematical formulae that calculate time allowances. PHRF has no need for any such formulae, as its arbitrary handicaps imply time allowances directly. PHRF offers simplicity, low cost, and elements of local control. However, it relies on owner input of basic hull and rig measurements, and it depends heavily on the sophistication and experience of its handicappers. These handicappers are in essence ‘umpires’, and like umpires they get many of their calls right, but inevitably some wrong. PHRF is said to be based loosely on the ‘Arbitrary Rule’ used on the West Coast in the 1940’s, and it has been in common use since the 1980’s. PHRF has possibly 25,000 ‘end users’, almost all of them sailing in US waters.

IRC (Formerly Channel Handicap System)

The Channel Handicap System (CHS) was developed cooperatively by English and French sailors in the early 1980’s. It was intended to suit cruiser/racers that were seen as disenfranchised by the flat out racers that had come to dominate big boat racing in the English Channel. During the 1990’s, CHS coexisted in parallel with the International Measurement System (IMS) in Channel racing, with the former generally suiting cruiser/racers, and the latter coming to serve mainly high end racers. Declining participation overseas suggested consolidating both groups under one rule, which led to the re-branding of CHS, essentially intact, as ‘IRC’ in 1999. Along with its new name, IRC took on new ownership, and in an arrangement unique in yacht handicapping, IRC is owned by a for-profit, Seahorse Rating Ltd, which is an offshoot of the magazine Seahorse. IRC’s commercial sponsorship is also unique, as has been its aggressive marketing. In response to a similar participation decline in US waters, East Coast race organizers likewise chose to consolidate big boat racing under one rule, and in 2005 they mandated the use of IRC in their races, to the exclusion of other rules, above an arbitrary boat size.

In addition to its for-profit ownership, IRC is unique in that its handicaps are produced via a combination of ‘hands off’ mathematical formulae and some limited human intervention. Basic hull and rig details, including displacement (weight), are physically measured, while some hull and appendage shape details that are troublesome to define by measurement are subjectively categorized, and related factors are used as modifiers to the base formulae. IRC is an unpublished ‘black box’ rule, so the precise workings of the rule are known only to its developers. IRC does not employ a computer ‘velocity prediction program’ (VPP) directly in establishing its handicaps, but it has been described as ‘VPP based’, so presumably VPP’s have been used as a tool in its development. IRC was initially promoted as a simpler alternative to IMS, but it is a tall order for a simple system to deal comprehensively with something as complex as predicting the performance of a wide variety of sailboat types. Stability, wetted area, and beam at the waterline are all primary performance parameters, but none of these are directly measured by IRC. Inevitably, IRC has been subject to heavy pressure from focused racers seeking competitive advantage, and over time some perceived ‘typeforms’ have been identified. As a result, top IRC race boats typically feature fractional rigs with swept spreaders, small ‘lapper’ jibs, low upwind sail area in smaller boats, large masthead spinnakers tacked to a bowsprit, deep ‘T’ bulb keels, and very broad beam aft. IRC certificates in the US numbered in the 700’s early on, but they have since declined to about 350.

ORR (Offshore Rating Rule)

The same decline in ‘big boat’ fleet sizes that prompted the New York Yacht Club to orchestrate the implementation of IRC lead the Chicago Yacht Club, the Cruising Club of America, and the Transpacific Yacht Club to collaborate in forming the Offshore Racing Association in 2004. This organization is convinced that a sophisticated (if not ‘simple’) VPP-driven handicapping system that is based on comprehensive physical measurement is the only way to reliably and accurately handicap a diverse fleet. They believe that there is a place for this type of rule in the existing mix of available handicapping systems among sailors who want to be able to race boats of the type that they themselves prefer to sail, rather than a type that is favored by a rating rule. The group’s Offshore Rating Rule (ORR) was first used in 2006.

Like IRC, ORR is maintained in an unpublished ‘black box’ form in an effort to reduce its exposure to unduly aggressive optimization in seeking a competitive advantage. ORR’s lineage goes all the way back to the Pratt Project VPP, developed at the Massachusetts Institute of Technology in the 1970’s, and it is a direct descendant of USSailing’s ‘Americap’ adaptation of that VPP. ORR is under continual development by a US-based technical team, with changes to its VPP based both on hard science (e.g. test tank, wind tunnel, and CFD studies) and on informed observation of real world performance. ORR performance predictions are based on direct measurement of rig and sails, and integrated values for wetted area, stability, beam at the waterline, effective sailing length, and sailing displacement, all based on full hull and appendage shape definition. ORR is best known for its use in open water events such as the Bermuda and Chicago/Mackinac races, but its popularity in windward/leeward short course racing has seen growth. A recent count showed about 700 boats with active ORR certificates, all in the US.

ORCi and ORC Club

The Offshore Racing Congress (ORC) is responsible for the continued development and implementation of their ORCi and ORC Club rules. ORCi is a direct descendant of the International Measurement System (IMS). It is essentially the same VPP-based system with a new name, and it is a robust system suitable for high end international competition. ORC Club is a variant of ORCi with somewhat less rigorous measurement requirements, and it is intended for local and club level racing. ORCi and ORC Club are in use overseas only, and so have limited relevance in the U.S.

HPR (High Performance Rule)

The HPR is recently introduced rule that intentionally and aggressively type-forms towards very light displacement, high performance designs. HPR was initially focused on boats of this type around 40 feet in overall length that have not fared well under IRC, which is perceived to type-form towards considerably heavier displacement and smaller upwind sail area in this size range. HPR might be best described as a ‘bowl’ type rule, that identifies target characteristics and parameters that are located in the middle of various mathematical ‘bowls’. It imposes increasingly stiff rating disincentives to straying very far up the sides of the bowl, and away from the intended parameter targets at the center. The HPR formulae are simple and published, so that owners and designers can engage in ‘what if’ optimizations to the rule as they wish. The HPR is intended to suit a very thin, but presumably growing, slice of boats at the very top of the performance (and participation) pyramid. It has been taken under the umbrella of the Offshore Racing Association (ORA) as a counterpoint to ORR, the group’s more general purpose rule that is intended to suit a much larger group of owners further down that same pyramid. It is hoped that the HPR will take root internationally. So far, there are 10 boats with HPR certificates, all in the U.S.

TP52 (Formerly Transpac 52)

The TP52 is a class that is defined by a classic ‘box’ rule. A ‘box’ rule is one that manages a class of intentionally very similar boats by establishing quite narrow limits on critical performance parameters. If a boat’s characteristics fall within these limits, she fits inside the ‘box’ and she can race level, without handicaps, with other boats in the class. This ‘box’ rule approach is quite different from a ‘measurement’ rule concept, that uses a more comprehensive set of measurements from each boat as inputs to mathematical formulae, which in turn generate the time allowances that allow a variety of design types to race together via handicaps. The TP 52 box rule approach can be attractive because it is simple, it imposes few restrictions on design, and it can provide close racing among like boats on a no- handicap ‘first to finish wins’ basis. This approach can also lead to very rapid design development and obsolescence in a new class, and it is prone to condition specific designs; boats optimized for light air and big breeze can both fit into the same class ‘box’, which can pre-ordain race results in some conditions and at some venues. The TP52 class was first established on the US West Coast in 2001. Its center of activity quickly shifted to the Mediterranean, where it flourished at an unabashedly grand prix, fully professional level for a number of years. There are currently about 15 boats holding TP52 class certificates worldwide, with 4 of those based in the US.