Q&A 2018-003
Rule A3; Starting Times and Finishing Places
In an event using a handicap/rating system, if no rule contains any provision for rounding a boat’s corrected time, rounding to any unit of time is incorrect.
Situation
In an event using a handicap/rating system, the notice of race and the sailing instructions make no reference regarding to how boats’ corrected times should be rounded (to the nearest second, up or down, how many digits, etc.).
The result may vary significantly depending on what system is used for rounding the result. For example: Two boats with corrected times of 02:23:14.5 and 02:23:15.4 would both round to 02:23:15. The 0.9 seconds in the above example reflects about 15 feet/4.5 meters when a boat is moving at 10 knots.
Question
Is it an error of the race committee to round the corrected time of the boats to the nearest second when the handicap/rating system makes no reference regarding rounding?
Answer
Yes. Rule A3 requires the finishing place to be determined by a boat’s corrected time.
Calculating a corrected time to any number of decimal places, implies a timing accuracy that does not exist. However, if no rule contains any provision for rounding a boat’s corrected time, rounding to any unit of time is incorrect.
Many rating systems, including IRC and ORC, specify that corrected times shall be rounded to the nearest second. In the absence of a provision in the rating system, the notice of race or the sailing instructions may contain such a provision stating that rule A3 is changed.