On Jan 8, 1:45*pm, wrote:
Guys, I think we're all stressed from lack of flying and need to calm
down a bit and stop over-analyzing this one.

Yes, the point of the "front half" business is to further discourage
starting out the back or back of the top and bumping gaggles along the
top edge of the start cylinder.

Yes, the area in which you get full credit for distance is described
by a gentle semicircle defined by the first turn fix. *Therefore, yes,
you don't know exactly where the area is before you get to the first
turnpoint.

However, nothing terrible happens to you if you start outside of the
"front half." No penalties, no invalid starts, nothing. You just don't
get full credit for distance. In typical starts out the top, a half
knot of extra thermal strength will be much more important than even
being a mile outside of the extra credit area. Remember, people used
to start out the top back when they got no credit at all for extra
distance. Knowing the exact location of the "extra credit" area is
just not that important.

Thus, if you want to start out the top, the right strategy is to look
for the best possible thermal in the front half to two thirds of the
start cylinder. Programming semicircles into your flight computer and
staring at that isn't going to do any good compared to looking for a
good thermal.

In these extreme situations such that you might be heading 30 degrees
to the left or right of "courseline" into a huge first turn area, let
me suggest that if you have no idea before start whether you're going
to head 30 degrees to the left or 30 degrees to the right, you need to
do some better pre-start thinking rather than worry about start
geometry!

Yes, this means that the very back of the start cylinder is
disadvantaged for starts out the top. The RC is very worried about the
"bump the gaggle" business, especially if the first leg is downwind.
We judged that at least to start with the benefit outweighs the cost.

In the future, we can remove or relax this rule if it is proving too
constraining. Another possibility is to remove some of the "last valid
start" language and let this simple rule alone police the "bump the
gaggles" problem. But clearly if we see bump the gaggles behavior, or
heaven forbid a crash, the whole start anywhere concept will be in
danger. Hence, we thought it better to start conservatively.

Let us know your experiences this year

John Cochrane BB

We do turn into tire-biters in the winter don't we?

Now, back at it:

John - I take your points on the scenarios probably being relatively
low probability If risk of traffic conflict in the start cylinder is
the big concern I can totally understand the RC taking a conservative
approach - the last thing you'd want to do is make a rule change that
gets somebody hurt or their glider broken. It's a big responsibility.

The conundrum is that the conservative approach is kind of like the
old joke about clapping your hands to keep the elephants away - the
only way to know if it works is to stop clapping, but who wants to
risk it? Inch by inch we add little complexities into the rules
because we can imagine something that might not be right about the
simple version. That of course means that it can be hard to work
these things out of the rules because you never know at what point the
elephants come back. But what if the elephants are just in our
imagining? It's not an easy question and please don't take this
discussion as criticism of what you guys do. I, for one, am just
trying to figure out what it means so I don't have to deal with in on
the fly next year.

Tuno's recommendation is a good one - which is to look at a reasonable
sample of 2007, 2008 and 2009 contests from the east and west, big and
small (especially big), with MSHs in all the various relationships to
top of lift and cloud base to see what pilots actually do differently.
The RC may do this already in some form. Obviously individual feedback
is the only way to know how people feel about the operational and
workload aspects of it.

Andy