Just a little exercise I did with some recent results of a club race.
"Sail to your PHRF #"
According to PHRF;
J-92 PHRF = 111 Pearson 26 PHRF 222
J-92 in light air 3600/(111+600) = 5.06kts PHRF's predicted average speed for light air
P-26 in light air 3600/(222+600) = 4.37kts PHRF's predicted average speed for light air
kt = knots; ktm = nautical miles
J-92 covered 4.5ktm in 2 hrs & 7 minutes or 2.17 hrs
4.5/2.17 = averaging 2.125 kts
P-26 covered 4.5 ktm in 2 hrs & 21 minutes
4.5/2.35hrs averaging 1.914 kts
J-92 5.06 - 2.12 = 3.04 ( predicted speed - actual speed)
P-26 4.37 - 1.91 = 2.46 ( predicted speed - actual speed)
The Pearson 26 sailed closer to what PHRF predicted he should sail in light air then the J-92.
Therefor the P-26 wins !!!!!
Roy
Note:
For medium air replace 600 with 550
For heavy air replace 600 with 480
neither boat sailed even close to what PHRF predicts.
Bottom line -- you are racing against the clock, not the other boats .....
Hershey
Posts: 424
Joined: Mon Jul 08, 2013 9:48 pm
Location: http://chelseayacht.org
Boat Name: Hershey II
Sail Number: 427
Boat Type: Wing Keel Standard Rig
"Sail to your PHRF #"
According to PHRF;
J-92 PHRF = 111 Pearson 26 PHRF 222
J-92 in light air 3600/(111+600) = 5.06kts PHRF's predicted average speed for light air
P-26 in light air 3600/(222+600) = 4.37kts PHRF's predicted average speed for light air
kt = knots; ktm = nautical miles
J-92 covered 4.5ktm in 2 hrs & 7 minutes or 2.17 hrs
4.5/2.17 = averaging 2.125 kts
P-26 covered 4.5 ktm in 2 hrs & 21 minutes
4.5/2.35hrs averaging 1.914 kts
J-92 5.06 - 2.12 = 3.04 ( predicted speed - actual speed)
P-26 4.37 - 1.91 = 2.46 ( predicted speed - actual speed)
The Pearson 26 sailed closer to what PHRF predicted he should sail in light air then the J-92.
Therefor the P-26 wins !!!!!
Roy
Note:
For medium air replace 600 with 550
For heavy air replace 600 with 480
neither boat sailed even close to what PHRF predicts.
Bottom line -- you are racing against the clock, not the other boats .....
Hershey
Posts: 424
Joined: Mon Jul 08, 2013 9:48 pm
Location: http://chelseayacht.org
Boat Name: Hershey II
Sail Number: 427
Boat Type: Wing Keel Standard Rig