NFS-Delta
About 10 years ago, the Speed Potential (handicap) for No Flying Sail (NFS) boats was decoupled from that of the Flying Sail (FS) handicap. This increased the work-load of Central Council and has also resulted in a tendency for the two handicaps to move apart. The current project is aimed at fixing many of the issues in the NFS handicaps and to rationalize the difference between the FS and NFS handicaps (Delta). This new Delta is solely based upon Velocity Prediction Program (VPP) analysis of optimum boat performance both with and without flying sails. In other words, a boat’s best performance downwind with a spinnaker compared to its best performance with only genoa and mainsail.
Genoa adjustments
Genoa size adjustment was also studied using the same database and the VPP. This has results in new values in the genoa size adjustment table. These changes are more in the nature of a smoothing rather than major changes although the small jibs do get significantly bigger allowances. At the same time we have started to drop the 3 sec increment for individual adjustment and in future adjustments will be rounded to the nearest whole number. The total adjustment and ASP will therefore not be an increment of 3.
Prop adjustments
It has long been felt that the current allowance for fixed blade props is not adequate to cover the lost performance due to drag. In order to improve fairness for cruising boats a range of boats sizes has been analyzed to determine the drag due to fixed 2 blade and 3 blade props. The resulting changes to the adjustment table are not large enough to cause skippers to move from folding to fixed but at least will create a more level field for the cruiser racer fleet.
Central Council review
Rest assured that Central Council, in the light of performance data, will scrutinize the application of these adjustments and the NFS Delta. Expect to see changes in both the FS and NFS handicaps for 2012.
This whole project, which will have taken nearly two years to complete, is part of a general movement to improve the objectivity within the PHRF-LO handicapping system. VPP is a very powerful tool and it is teaching us a lot. You may expect more developments as we discover soft spots in the system.
Regards,
Brian Thomson – Chief Handicapper PHRF-LO
Andrew Sensicle – Technical Advisory Committee PHRF-LO
Links:
2012 - Handicappers Manual - Jib/Genoa adjustment table **
2012 - Handicappers Manual – Downwind Jib adjustment table **
2012 - Handicappers Manual - Propulsion adjustment table **
2012 – Class List with NFS-Delta
** Unfortunately, incorrect adjustment tables were initially being displayed on Dec 29th. All files have now been corrected.