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Made Easy. Time on Time. By Robert S. Porter Assnt . Chief Handicapper PHRF – Lake Ontario. a PHRF Primer. Time on Time Made Easy. So easy, even Jim Teeters can understand it. Time on Time. Goal: To compare and contrast: Time on Time ( ToT ) and Time on Distance ( ToD )
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Made Easy Time on Time By Robert S. Porter Assnt. Chief Handicapper PHRF – Lake Ontario a PHRF Primer
Time on TimeMade Easy So easy, even Jim Teeters can understand it.
Time on Time Goal: To compare and contrast: Time on Time (ToT) and Time on Distance (ToD) Handicapping Made Easy Time on Time – a PHRF Primer
Time on Time Process: Handicap “standard” yachts in windward/leeward races of varying wind strengths. Made Easy Time on Time – a PHRF Primer
Time on Time Outcome: Identify result differences between ToT and ToD • Closeness of finish places • Distribution of finish places Made Easy Time on Time – a PHRF Primer
Time on Distance (ToD) Time on Distance Handicapping Arrives at a yacht’s corrected elapsed time by: Multiplying a yacht’s handicap in seconds per mile by the course length Then subtracting (or adding) the result from (or to) it’s elapsed time. It is independent of : a yacht’s elapsed time. Time on Time – a PHRF Primer
Time on Time (ToT) Time on Time Handicapping Arrives at a yacht’s corrected elapsed time by: Multiplying a yacht’s elapsed time (in seconds) around a course By a time correction factor (handicap multiplier). It is independent of : race course length. 12 9 3 6 Time on Time – a PHRF Primer
Race Course A one nautical mile course, sailed twice around (two upwind legs/ two downwind legs) 4 miles in length One Mile Time on Time – a PHRF Primer
Handicap Yacht’s Elapsed Time = Upwind VMG x 2 km + Downwind VMG x 2 km (in seconds) VMGs provided by US Sailing – Offshore Office Time on Time – a PHRF Primer
Handicap Time on Distance Handicap (sec/km) x Course Length (km) subtracted from the Yacht’s Elapsed Time = Corrected Time Time on Time – a PHRF Primer
Handicap Time on Time Yacht’s Elapsed Time x a Yacht’s Time Conversion Factor (TCF) = Corrected Time Time on Time – a PHRF Primer
Time Conversion Factor Time on Time [A yacht with a “0” handicap is expected to complete a one mile course in 650 seconds] Mean (0) boat’s sec/mi 650.000 650.000 + PHRF TCF = 0 boat’s sec/mi PHRF sec/mi As recommended by US PHRF Time on Time – a PHRF Primer
PHRF - LO Time on Time PHRF Lake Ontario has been using ToT scoring for the past 25 years. Currently, PHRF-LO has 1600 yachts racing with current certificates Each year PHRF-LO does a statistical analysis of 90% of all races (club & regattas) – mostly windward/leeward www.PHRF-LO.org Time on Time – a PHRF Primer
PHRF - LO Time on Time The PHRF-LO experience with using Time on Time has developed the following ToT formula. 566.431 401.431 + PHRF TCF = Time on Time – a PHRF Primer
PHRF - LO Time on Time [The median yacht in PHRF-LO is handicapped at 165 and the “0” yacht has been proven to complete a 1 km course in ~401 seconds] Mean boat’s (165) sec/km 566.431 401.431 + PHRF TCF = 0 boat’s sec/km PHRF sec/km As used by PHRF-LO Time on Time – a PHRF Primer
Race Boats Select PHRF Let us identify 3 US Sailing PHRF “Standard” Yachts to compare sailing under ToT and ToD. J24 C&C 35 J35 Time on Time – a PHRF Primer
Race Boats J35 Boat Preparation Crew Ability Skipper Ability Sails It is defined that all yachts are equally prepared and sailed. They sail at 100% of VMG Time on Time – a PHRF Primer
168 sec/km x 4 miles = -672 sec Race Boats J24 ToDHandicap: ToTHandicap: 566.431 401.431 + 168 TCF = 0.9947 Time on Time – a PHRF Primer
129 sec/km x 4 miles = -516 sec Race Boats C&C 35 ToDHandicap: ToTHandicap: 566.431 401.431 + 129 TCF = 1.0679 Time on Time – a PHRF Primer
72 sec/km x 4 miles = -228 sec Race Boats J35 ToDHandicap: ToTHandicap: 566.431 401.431 + 72 TCF = 1.1964 Time on Time – a PHRF Primer
Lets Go Sailing! Time on Time – a PHRF Primer
Wind Race #1 6 knots of wind Lets Go Sailing! Race #2 12 knots of wind Race #3 20 knots of wind Wind is perfectly constant during each race, and parallel to the race course Time on Time – a PHRF Primer
Race #1 6 knots of wind Lets Go Sailing! J24 @ 1283.1 sec/km @ 1231.2 sec/km Total elapsed time 5028.6 sec (83:48.6) Time on Time – a PHRF Primer
Race #1 6 knots of wind Lets Go Sailing! C&C 35 • @ 1225.3 sec/Km • @ 1137.1 sec/km • Total elapsed time 4724.8 sec • (78:88.8) Time on Time – a PHRF Primer
Race #1 6 knots of wind Lets Go Sailing! J35 @ 1034.5 sec/km @ 1071.9 sec/km Total elapsed time 4212.8 sec (70:12.8) Time on Time – a PHRF Primer
Wind Race #1 6 knots of wind Lets Go Sailing! How did we do? ToD Boat ET Hdp CET J24 5028.6 -672 4356.6 C&C 35 4724.4 -516 4208.8 J35 4212.8 -288 3924.8 Time on Time – a PHRF Primer
Wind Race #1 6 knots of wind Lets Go Sailing! How did we do? ToT Boat ET Multiplier CET J24 5028.6 x 0.9947 5001.9 C&C 35 4724.8 x 1.0679 5045.6 J35 4212.8 x 1.1964 5040.2 Time on Time – a PHRF Primer
Wind Race #1 6 knots of wind Lets Go Sailing! How did we do? ToD 1st J35 0.0 2nd C&C 35 284.0 3rd J24 431.6 ToT 1st J24 0.0 2nd J35 38.3 3rd C&C 35 43.7 Time on Time – a PHRF Primer
Race #2 12 knots of wind Lets Go Sailing! J24 @ 893.9 sec/km @ 679.2 sec/km Total elapsed time 3146.2 sec (52:26.2) Time on Time – a PHRF Primer
Race #2 12 knots of wind Lets Go Sailing! C&C 35 @ 844.3 sec/km @ 622.6 sec/km Total elapsed time 2933.8 sec (48:53.8) Time on Time – a PHRF Primer
Race #2 12 knots of wind Lets Go Sailing! J35 @ 720.9 sec/km @ 594.7 sec/km Total elapsed time 2631.2 sec (43:51.2) Time on Time – a PHRF Primer
Wind Race #2 12 knots of wind Lets Go Sailing! How did we do? ToD Boat ET Hdp CET J24 3146.2 -672 2474.2 C&C 35 2933.8 -516 2417.8 J35 2631.2 -288 2343.2 Time on Time – a PHRF Primer
Wind Race #2 12 knots of wind Lets Go Sailing! How did we do? ToT Boat ET Multiplier CET J24 3146.2 x 0.9947 3129.5 C&C 35 2933.8 x 1.0679 3133.0 J35 2631.2 x 1.1964 3148.0 Time on Time – a PHRF Primer
Wind Race #2 12 knots of wind Lets Go Sailing! How did we do? ToD 1st J35 0.0 2nd C&C 35 74.6 3rd J24 131.0 ToT 1st J24 0.0 2nd C&C 35 3.5 3rd J35 18.5 Time on Time – a PHRF Primer
Race #3 20 knots of wind Lets Go Sailing! J24 @ 828.5 sec/km @ 524.6 sec/km Total elapsed time 2706.2 sec (45:06.2) Time on Time – a PHRF Primer
Race #2 20 knots of wind Lets Go Sailing! C&C 35 @ 773.8 sec/km @ 484.9 sec/km Total elapsed time 2517.4 sec (41:57.4) Time on Time – a PHRF Primer
Race #3 20 knots of wind Lets Go Sailing! J35 @ 663.5 sec/km @ 456.1 sec/km Total elapsed time 2239.2 sec (37:19.2) Time on Time – a PHRF Primer
Wind Race #3 20 knots of wind Lets Go Sailing! How did we do? ToD Boat ET Hdp CET J24 2706.2 -672 2034.2 C&C 35 2517.4 -516 2201.4 J35 2239.2 -288 1951.2 Time on Time – a PHRF Primer
Wind Race #3 20 knots of wind Lets Go Sailing! How did we do? ToT Boat ET Multiplier CET J24 2706.2 x 0.9947 2691.8 C&C 35 2517.4 x 1.0679 2688.3 J35 2239.2 x 1.1964 2679.0 Time on Time – a PHRF Primer
Wind Race #3 20 knots of wind Lets Go Sailing! How did we do? ToD 1st J35 0.0 2nd J24 83.0 3rd C&C 35 250.2 ToT 1st J35 0.0 2nd C&C 35 9.3 3rd J24 12.8 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? Yacht 6kts 12kts 20kts Ave. ToD J24 3rd 3rd 2nd 2.67 C&C 35 2nd 2nd 3rd 2.33 J35 1st 1st1st 1.00 ToT J24 1st 1st 3rd 1.67 C&C 35 3rd 2nd2nd 2.67 J35 2nd 3rd 1st 2.00 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? Place 6kts 12kts 20kts Ave. ToD 1st 0 0 0 0.00 2nd 284.0 74.6 83.0 147.2 3rd 431.6 131.0 250.3 271.9 ToT 1st 0 0 0 0.00 2nd 38.3 3.5 9.3 17.0 3rd 43.7 18.5 12.8 25.0 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? Sec/km Place 6kts 12kts 20kts Ave. ToD 1st 0 0 0 0.00 2nd 71.0 74.6 18.6 36.8 3rd 107.9 32.7 62.6 68.0 ToT 1st 0 0 0 0.00 2nd 9.6 0.9 2.3 4.3 3rd 10.9 4.6 3.2 6.2 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? @ 90% vmg Lets take a look at how racing at 90% of VMG will impact race results. Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? @ 90% vmg Yacht 6kts 12kts 20kts Ave. ToD J24 3rd 3rd3rd3.00 C&C 35 2nd 2nd2nd2.00 J35 1st 1st1st 1.00 ToT J24 1st 1st 3rd 1.67 C&C 35 3rd 2nd2nd 2.67 J35 2nd 3rd 1st 2.00 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? @ 90% vmg Place 6kts 12kts 20kts Ave. ToD 1st 0 0 0 0.00 2nd 85.2 27.0 20.5 44.4 3rd 130.6 46.9 33.7 70.4 ToT 1st 0 0 0 0.00 2nd 10.6 1.0 2.6 4.7 3rd 12.1 5.1 3.6 6.9 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? Sec/km Place 100% vmg 90% vmg ToD 1st0.00 0.00 2nd36.844.4 3rd68.070.4 ToT 1st0.00 0.00 2nd4.24.7 3rd6.26.9 Time on Time – a PHRF Primer
Wind Compilation of Results Lets Go Sailing! How did we do? ToT – US S Race 6kts 12kts 20kts Ave. ToT 1st 0 0 0 0.00 PHRF-LO 2nd 38.3 3.5 9.3 17.0 3rd 43.7 18.5 12.8 25.0 ToT 1st 0 0 0 0.00 US Sailing2nd 42.6 4.0 10.5 19.0 3rd 48.8 20.5 14.2 27.8 Time on Time – a PHRF Primer
Wind Lets Go Sailing! Time on Distance must know exact course length error in course length = error in time adjustment. (1% error(60 ft) ~ 6-12 s/m) Racers know handicap at start of race Correction does not increase during “no-wind” conditions. Time on Time – a PHRF Primer
Wind Lets Go Sailing! Time on Time Racers do not know handicap at start of race Correction increases during “no-wind” conditions. Need not know course length Error in course length does not = handicap error Time on Time – a PHRF Primer