Measuring Up

Handicapping Formula

The GCBSR uses a rating factor handicapping (also known as time on time) method for calculating the corrected time for each vessel.  Boats of similar rating factor should perform similarly. The corrected time is calculated:

Corrected Time = Actual Elapsed Time * Rating factor

where the rating factor is calculated:

Rating Factor = √Rated Length / √40

finally the rated length is based on the 1974 Off Soundings Club Rating Rule:

Rated Length=[ {L + (2 * √MSA * RA)} / 2.5 ]*PA
where L=PL +/- BC
PL=( LOA + LWL ) / 2
BC=2 * ( LOA / 4 – beam )
MSA=Measured sail area
PA=Propeller Allowance
RA=Rig Allowance

The critical elements of this formula are the boat’s dimensions, sail area, prop and rig type. Measured Sail Area is the theoretical area available for lowers, and reflects the rig type and size, not the boat’s sail inventory. There is no provision for spinnakers, topsails, etc. so boats carrying these sails have some initial advantage.

   

Because the rating factor based on rated length is only a first approximation of the boat’s performance, the rating factor is then further adjusted each year based on the cumulative performance of the vessel vis-à-vis the rest of the racing fleet in all previous races. Statistical methods are used to develop an accurate handicap for each vessel. The Rating Factor has been calculated for every boat that has participated in the Race since 1999.

Vessels with larger Rating Factors will wind up “owing time” to vessels with a lower Rating factor.  The list of 2019 Rating factors for schooners that have raced in the past 20 years can be found here. If you want to read more about the handicapping method, read Why and How.

FLEETS AND CLASSES

The handicapping method used allows any two boats to be meaningfully raced against each other, however, there is a desire among the GCBSR fleet to race similar types of boats against each other. Therefore, classes are established based on rig and vessel size. Classes have changed over the years, as has the course length for each class. This year’s classes will be:

AA: Traditional, larger vessels (rated length 35ft or greater)
A: Modern, larger vessels (rated length 35ft or greater)
B: Traditional, smaller vessels (rated length below 35ft)
C: Modern, smaller vessels (rated length below 35ft)

The criteria that define a vessel as modern are: unstayed rigs, fully-battened sails, marconi or staysail foresail rigs & spinnakers. Essentially, if it wasn’t in use in the 1920’s then it counts as modern. 

The dividing length between larger and smaller may be adjusted year by year to balance the size of the classes. 

There are two fleets that race in the GCBSR:

Thimble Shoal Fleet (118 nm course)
Class AA and Class A 

Windmill Point Fleet (83 nm course)
Class B and Class C 

The race committee reserves the right to make appropriate adjustments in rating factor or class placement until the vessel becomes competitive. The first time a schooner competes, she normally races without adjustment. The vessel’s previous performance will be used to adjust the vessel’s rating. If you question your rating, please review the issue with the race committee.