Handicapping
Handicapping is the single most device topic in any form of sailing that is not pure one design. The following information provides some explanation of two main handicapping systems used in trailer sailer racing. CBH (Class Based Handicap) and PHS (Performance Handicap System).
Despite the amount of effort and emotion expended in developing handicap systems there is no such thing as a perfect handicapping system. They all have limitations including CBH and PHS. Both CBH and PHS are appropriate handicapping systems for trailer yachts and are as effective as any of the alternatives.
Read the definitions and explanation below of each so that you understand how the handicapping systems work and why there is little value in expending any energy in arguing with the handicapper. The handicappers job is simply to apply a predetermined mathematical equation using the time you took to sail around the course.
At the end of the race you know whether you sailed well or not. You can also tell if you sailed well by where you finish relative to the boats around you. If you sailed well and you finished in front of the boats you normally finish behind then be very satisfied with yourself that you had a good day out!
Sailing is a challenging sport and it is all about sailing well and making less mistakes than your competitors. If you sail well and are lucky enough that the weather conditions and course are ideal for your design of boat, it may be your day and you will get onto the handicap podium!
Despite the amount of effort and emotion expended in developing handicap systems there is no such thing as a perfect handicapping system. They all have limitations including CBH and PHS. Both CBH and PHS are appropriate handicapping systems for trailer yachts and are as effective as any of the alternatives.
Read the definitions and explanation below of each so that you understand how the handicapping systems work and why there is little value in expending any energy in arguing with the handicapper. The handicappers job is simply to apply a predetermined mathematical equation using the time you took to sail around the course.
At the end of the race you know whether you sailed well or not. You can also tell if you sailed well by where you finish relative to the boats around you. If you sailed well and you finished in front of the boats you normally finish behind then be very satisfied with yourself that you had a good day out!
Sailing is a challenging sport and it is all about sailing well and making less mistakes than your competitors. If you sail well and are lucky enough that the weather conditions and course are ideal for your design of boat, it may be your day and you will get onto the handicap podium!
Trailer yacht regatta's should endeavour to provide results using both the CBH and PHS handicapping systems. An individual yacht that podiums under CBH should not be eligible for a PHS result. Share the silverware and accolades far and wide.
Whilst more work for the regatta officials further interest can be created by estimating the race duration (normally targeted at 90 minutes) and calculating the start time offset for each competing trailer yacht such that their result is determined by their relative position over the finish line.
Whilst more work for the regatta officials further interest can be created by estimating the race duration (normally targeted at 90 minutes) and calculating the start time offset for each competing trailer yacht such that their result is determined by their relative position over the finish line.
Corrected Race Time
Corrected time = a trailer yachts elapsed race time in minutes x the trailer yachts handicap (CBH or PHS)
Corrected time = a trailer yachts elapsed race time in minutes x the trailer yachts handicap (CBH or PHS)
Class Based Handicap (CBH). CBH is a basic measured rule and uses a suite of measurements to estimate the theoretical performance of a trailer yacht. These measurements include; sail area, overall length, water line length, maximum beam, keel & rudder type, overall weight, keel weight, construction material, mast/boom/spinnaker pole size and materials, standing & running rigging.
The CBH calculation is based on the old Junior Offshore Group (JOG) rule that was a measurement system developed in the UK in the 1950's for small yachts. Where necessary the theoretical handicap figures generated by this measurement system are adjusted on the basis of actual performance information (ie race results) and other empirical evidence to ensure a fair and even system of rating the potential performance of trailer yachts. The national CBH ratings are administered by Austrailian Trailer Yacht & Sports Boat Rule Technical Committee under Australian Sailing and are periodically reviewed.
As noted the CBH system uses basic measurements to calculate a theoretical performance handicap after which the technical committee overlay some subjective evidence based experience to "tweak" the handicap in the interests of fairness. As such whilst the CBH system is a basic measured system it is not a pure measurement system and can be compromised for the average sailor when a particular class of trailer yacht is sailed by exceptionally skilled sailors or when there are very small numbers of a particular class of trailer yacht. It can also be compromised by individual trailer yacht modifications that move particular trailer yachts away from class standard.
Modern technology means there is now the capability to adopt a pure measured handicapping system that uses the exact hull, appendage and sail form & mass. This information is then run through a computerised Velocity Prediction Programme to develop an accurate handicap for a fleet of trailer yachts. However, this is extremely time consuming and expensive (quite possibly more than the value of a trailer yacht!). It is for this reason that the CBH rating system remains appropriate for Trailer Yachts.
The CBH calculation is based on the old Junior Offshore Group (JOG) rule that was a measurement system developed in the UK in the 1950's for small yachts. Where necessary the theoretical handicap figures generated by this measurement system are adjusted on the basis of actual performance information (ie race results) and other empirical evidence to ensure a fair and even system of rating the potential performance of trailer yachts. The national CBH ratings are administered by Austrailian Trailer Yacht & Sports Boat Rule Technical Committee under Australian Sailing and are periodically reviewed.
As noted the CBH system uses basic measurements to calculate a theoretical performance handicap after which the technical committee overlay some subjective evidence based experience to "tweak" the handicap in the interests of fairness. As such whilst the CBH system is a basic measured system it is not a pure measurement system and can be compromised for the average sailor when a particular class of trailer yacht is sailed by exceptionally skilled sailors or when there are very small numbers of a particular class of trailer yacht. It can also be compromised by individual trailer yacht modifications that move particular trailer yachts away from class standard.
Modern technology means there is now the capability to adopt a pure measured handicapping system that uses the exact hull, appendage and sail form & mass. This information is then run through a computerised Velocity Prediction Programme to develop an accurate handicap for a fleet of trailer yachts. However, this is extremely time consuming and expensive (quite possibly more than the value of a trailer yacht!). It is for this reason that the CBH rating system remains appropriate for Trailer Yachts.
Performance Handicap System (PHS). PHS is a handicapping system that only considers the performance of an individual trailer yacht, crew and equipment relative to others. PHS handicaps can be compromised quite badly if there is no or little historical data for an individual trailer yacht/crew/equipment combination or through a skipper changing the crew, trailer yacht equipment or configuration.
There is no prescribed way to calculate PHS handicap's and depending on the methodology applied the handicaps can be stable (close to the CBH system) or continually varying. There are arguments both way's but generally a methodology that shares the results equitably across the fleet over time will satisfy most sailors.
The following methodology has proven to be quite effective. If there is no fleet or individual boat history then the CBH rating is good a starting place. The CBH ratings are also a good datum reference to ensure that PHS ratings do not drift too far. After the first race is run, start by selecting a "datum" boat that is approximately 45% from the top and is known to be a consistent performer. Using the datum boat, back calculate the handicap for each boat in the fleet such that it would end up with exactly the corrected time of the datum boat. One of two common approaches is then applied to "average" the back calculated handicaps to arrive at the handicap for the next race.
1. Average of the last 5 BCHs that were within 3% of the last PHS handicap equals the handicap for the next race
2 Exponential average. 1/3 BCH x 2/3 CBH equals the handicap for the next race
The first works well where there is good race history for the fleet. The second works well were there is little race history for the fleet. topyacht.com.au/web/wp-content/uploads/2017/03/PHS-handicapping-a-sailors-guide.pdf
There is no prescribed way to calculate PHS handicap's and depending on the methodology applied the handicaps can be stable (close to the CBH system) or continually varying. There are arguments both way's but generally a methodology that shares the results equitably across the fleet over time will satisfy most sailors.
The following methodology has proven to be quite effective. If there is no fleet or individual boat history then the CBH rating is good a starting place. The CBH ratings are also a good datum reference to ensure that PHS ratings do not drift too far. After the first race is run, start by selecting a "datum" boat that is approximately 45% from the top and is known to be a consistent performer. Using the datum boat, back calculate the handicap for each boat in the fleet such that it would end up with exactly the corrected time of the datum boat. One of two common approaches is then applied to "average" the back calculated handicaps to arrive at the handicap for the next race.
1. Average of the last 5 BCHs that were within 3% of the last PHS handicap equals the handicap for the next race
2 Exponential average. 1/3 BCH x 2/3 CBH equals the handicap for the next race
The first works well where there is good race history for the fleet. The second works well were there is little race history for the fleet. topyacht.com.au/web/wp-content/uploads/2017/03/PHS-handicapping-a-sailors-guide.pdf
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