At 12:20 15/07/2009, you wrote:
My 2 cents worth (using f3j experience). Timing to 1/10th of a second allows the human error of the timer to become a factor in the overall results. witness the last f3j world championship where after 4 fly off rounds the top 4 pilots where only separated by .7 of a second (I think). I'd suggest timing to the last completed second. Simple and effective. Regards Mark
Hi Mark,Please think twice, it is not as simple as that. With F3J you start the stopwatch at release from the towline and stop it once the glider touches the ground. Given a timepiece accuracy of 1/10 s and a reaction time of (with good timekeepers) also 1/10 s, the precision of the recorded flight time is in the region of 0.4 s (meaning, by the way, that the winning time for one flight cannot be more precise than 0.4 s, or several seconds for the final results in Turkey).
With the 5x2 task you are timing five flights in succession and the errors accumulate at launch and catch. A simulation I made shows that when timing to the full second, the total inaccuracy may reach 6 or 7 seconds. In other words, two pilots succeeding the exact same total flight time may find themselves separated by this amount in the official result. The problem is : is it acceptable for a final round that decides the winner ? The inaccuracy is less when timing to the nearest full second (but still up to 5 seconds in my simulation) and still less when timing to the tenth of second, although still more than one full second.
So the problem is : what is acceptable ?The problem is also : how to time ? I believe that in a few years' time we will end up with automatic timing, but it is probably too early to work on that. At this time, we must already realise that a final round with 8 pilots actually means 24 people on the field (pilots, helpers and timekeepers) and it may already be confusing for spectators.
Guy R.
