At 01:09 PM 3/4/2002 -0800, Giles Douglas wrote:
>The total time it takes to run the event depends on the start time between
>cars.
This is pretty much true. However, you have to add in downtime, like the
midday course walkthrough, driver's meeting, worker changeovers, and any
event stoppages (red flags, course cleanup after an exploding engine,
massive course reconstruction after a 40 cone run, etc.).
>The start time between cars depends on the overlap of the course (ie the
>number of cars on course at one time).
Nope. The number of cars on course at one time is totally dependant on the
length of the course, and the start interval between one car and the next.
>The limiting factors here are the
>total the clocks can cope with, and the safety aspects of the course (and
>probably the relative speeds of the drivers).
The factors that determine the start interval are:
1. How fast the trailer crew can shuffle cards and get ready for the next car.
2. The speed differential between the car on course and the car being
started.
3. How fast the average course worker can go out and fix a hit cone.
4. Features on the course (like a crossover) that would have cars pointed
at each other, or otherwise doing something dangerous and unwise.
5. The esthetic beauty and balance of the course design, the cars, the
weather, and the site. The flow of chi through the event site. The
gestalt of the event.
(actually, this last one is just in honor of all of Katie's "Zen
Autocrossing" posts...)
>Therefore, the total time it takes to run an event depends on (but not
>only on) the number of cars on course at one time, and the length of the
>course. This is the opposite of the earlier poster's comment that
>"Actually the number of cars on course simultaneously has very little to
>do with how many cars can get through the event" since the event time is
>usually constrained by the site.
Nope. The length of the course is a very minor part of the overall event
duration - it ends up being added to the calculations as the time necessary
for the very last car to complete it's run. The number of cars on course
at one time has absolutely nothing to do with the overall event duration.
Let's do some examples. First, let's say we have 100 cars doing 1 run
each. With a 70 second course, and a 25 second start interval, we end up with:
100 x 25 = 2500 seconds + 70 = 2570 seconds.
Now, let's say we have the same 100 cars doing 1 run each, with a 25 second
start interval. But this time, let's say we have a 10 second course. We get:
100 x 25 = 2500 seconds + 10 = 2510 seconds.
In the first example, the course is long enough to always have 2 cars,
sometimes 3, on course simultaneously. In the second, the course only has
one car on it at a time, and more often than not, is empty. However, the
overall duration of the event is approximately the same.
Of course, the number of cars on course simultaneously does determine the
impact of a red flag, or a car stopped for a down cone. If there are many
cars, you have to give them all reruns. If there's only one car on course
at a time, then the hit is only one rerun.
>However, it is still true that if you just lengthen the course by 15
>seconds to let you have one more car on the course at the same time then
>you might not, in fact, gain anything, which I think is the point the
>original poster was trying to make.
Whether you lengthen or shorten the course really doesn't matter - do the
math. The overall duration of the event is mostly determined by the
interval between starts.
Jim
|