2009 Proposed US Contest Rules Changes

Hi Race Fans
The proposed contest rules changes for 2009 are available at the SSA
web site under Sailplane Racing/Rules& Process. Due to a long time in
developing some of these changes the comment period will be quite
short. Please comment to RC members by 1/7/2009. Debate on this site
will be used as grist for coming activities but is not considered
formal feedback.
Respectfully submitted
For the Rules Subcommittee
H Nixon RC Chair

On Jan 3, 3:31*pm, wrote:
Hi Race Fans
The proposed contest rules changes for 2009 are available at the SSA
web site *under Sailplane Racing/Rules& Process. Due to a long time in
developing some of these changes the comment period will be quite
short. Please comment to RC members by 1/7/2009. Debate on this site
will be used as grist for coming activities but is not considered
formal feedback.
Respectfully submitted
For the Rules Subcommittee
H Nixon *RC Chair

(quote) Rule 10.8.6 has been changed such that starts will only
receive distance credit for distance flown from the“front” half of a
start cylinder.

The distance of the first task leg shall be taken as the distance from
the Start
Position to the control fix at the first turnpoint, but not greater
than the distance
from the Start Point to that control fix. (end quote)

The change to rule 10.8.6 appears to be intended to discourage starts
from the back half of the start cylinder. The comment suggests that
any start from the front half will score actual distance flown.
However, it appears that pilots starting near the back boundary of the
front half may fly non scoring distance without realizing it.

Consider the following worst case: Start cylinder 5 mile radius, area
task with first control area of 30 mile radius, center of first turn
area is 40 miles from start point. This gives a minimum first leg of
5 miles.

The proposed rule states - The distance of the first task leg shall be
taken as the distance from the Start Position to the control fix at
the first turnpoint, but not greater than the distance from the Start
Point to that control fix. This means the full score area of the
start cylinder is defined by an arc drawn from the first area control
fix through the start point. If the control fix happens to be near
the center of the first turn area then the arc will intersect the
start cylinder edges close to the straight line that defines the front
half. However, if the pilot chooses to turn anywhere except on a
straight line drawn through the start point and the first control
point, the arc will intersect the start cylinder away from the front
half line. The extreme case appears to be when the first turnpoint
control fix is on the edge of the turn area at a point that is on a
tangent drawn from the start point. There are two such points.

The worse case scenario is realized when a pilot starts the task close
to the edge of the back half on the assumption he will fly to one
tangent point and, because of a change in conditions, actually flies
to the other tangent point.

In a simple graphic analysis of the defined task I estimated a
distance of over 8 miles of start cylinder circumference between the
intersections of the two extreme case arcs and the start circle. In
other words, the potential front half circumference of approx 31.4
miles is reduced to a no risk arc of approx 23.4 miles. Someone with a
greater enjoyment of math will come up with a more accurate answer.

How, with the proposed rule change, is the pilot expected to know
whether the selected start cylinder exit point will result in a
devalued first leg distance?

Andy

On Jan 6, 3:25*pm, Andy wrote:
On Jan 3, 3:31*pm, wrote:

Hi Race Fans
The proposed contest rules changes for 2009 are available at the SSA
web site *under Sailplane Racing/Rules& Process. Due to a long time in
developing some of these changes the comment period will be quite
short. Please comment to RC members by 1/7/2009. Debate on this site
will be used as grist for coming activities but is not considered
formal feedback.
Respectfully submitted
For the Rules Subcommittee
H Nixon *RC Chair

(quote) Rule 10.8.6 has been changed such that starts will only
receive distance credit for distance flown from the“front” half of a
start cylinder.

The distance of the first task leg shall be taken as the distance from
the Start
Position to the control fix at the first turnpoint, but not greater
than the distance
from the Start Point to that control fix. (end quote)

The change to rule 10.8.6 appears to be intended to discourage starts
from the back half of the start cylinder. *The comment suggests that
any start from the front half will score actual distance flown.
However, it appears that pilots starting near the back boundary of the
front half may fly non scoring distance without realizing it.

Consider the following worst case: *Start cylinder 5 mile radius, area
task with first control area of 30 mile radius, center of first turn
area is 40 miles from start point. *This gives a minimum first leg of
5 miles.

The proposed rule states - The distance of the first task leg shall be
taken as the distance from the Start Position to the control fix at
the first turnpoint, but not greater than the distance from the Start
Point to that control fix. *This means the full score area of the
start cylinder is defined by an arc drawn from the first area control
fix through the start point. *If the control fix happens to be near
the center of the first turn area then the arc will intersect the
start cylinder edges close to the straight line that defines the front
half. * However, if the pilot chooses to turn anywhere except on a
straight line drawn through the start point and the first control
point, the arc will intersect the start cylinder away from the front
half line. * The extreme case appears to be when the first turnpoint
control fix is on the edge of the turn area at a point that is on a
tangent drawn from the start point. There are two such points.

The worse case scenario is realized when a pilot starts the task close
to the edge of the back half on the assumption he will fly to one
tangent point and, because of a change in conditions, actually flies
to the other tangent point.

In a simple graphic analysis of the defined task I estimated a
distance of over 8 miles of start cylinder circumference between the
intersections of the two extreme case arcs and the start circle. *In
other words, the potential front half circumference of approx 31.4
miles is reduced to a no risk arc of approx 23.4 miles. Someone with a
greater enjoyment of math will come up with a more accurate answer.

How, with the proposed rule change, is the pilot expected to know
whether the selected start cylinder exit point will result in a
devalued first leg distance?

Andy

I had to read that one three times -- and get out my daughter's high-
school geometry textbook ;-)

I had a similar reaction - but without the analytic rigor. Andy, I
assume you were using the minimum first leg distance (is there a
minimum beyond the cylinders not touching?) coupled with the maximum
turn area radius (30 mi). It's a problem in that the acceptable start
locations are not defined until after a pilot starts, and even if it
were defined, it's hard for a pilot to know for certain if they are in
the "front half".

I am assuming that the problem this is designed to solve is the one of
pilots starting out the top near the back of the cylinder and bumping
gaggles on the way to the front. Maybe others have seen this happen
but I have not, and I can't imagine anyone starting out the back side
of the cylinder. So I wonder if it is worth the complexity to solve a
problem that may not exist - at least not to a significant extent.

9B

9B

On Jan 6, 5:26*pm, wrote:
On Jan 6, 3:25*pm, Andy wrote:





On Jan 3, 3:31*pm, wrote:

Hi Race Fans
The proposed contest rules changes for 2009 are available at the SSA
web site *under Sailplane Racing/Rules& Process. Due to a long time in
developing some of these changes the comment period will be quite
short. Please comment to RC members by 1/7/2009. Debate on this site
will be used as grist for coming activities but is not considered
formal feedback.
Respectfully submitted
For the Rules Subcommittee
H Nixon *RC Chair

(quote) Rule 10.8.6 has been changed such that starts will only
receive distance credit for distance flown from the“front” half of a
start cylinder.

The distance of the first task leg shall be taken as the distance from
the Start
Position to the control fix at the first turnpoint, but not greater
than the distance
from the Start Point to that control fix. (end quote)

The change to rule 10.8.6 appears to be intended to discourage starts
from the back half of the start cylinder. *The comment suggests that
any start from the front half will score actual distance flown.
However, it appears that pilots starting near the back boundary of the
front half may fly non scoring distance without realizing it.

Consider the following worst case: *Start cylinder 5 mile radius, area
task with first control area of 30 mile radius, center of first turn
area is 40 miles from start point. *This gives a minimum first leg of
5 miles.

The proposed rule states - The distance of the first task leg shall be
taken as the distance from the Start Position to the control fix at
the first turnpoint, but not greater than the distance from the Start
Point to that control fix. *This means the full score area of the
start cylinder is defined by an arc drawn from the first area control
fix through the start point. *If the control fix happens to be near
the center of the first turn area then the arc will intersect the
start cylinder edges close to the straight line that defines the front
half. * However, if the pilot chooses to turn anywhere except on a
straight line drawn through the start point and the first control
point, the arc will intersect the start cylinder away from the front
half line. * The extreme case appears to be when the first turnpoint
control fix is on the edge of the turn area at a point that is on a
tangent drawn from the start point. There are two such points.

The worse case scenario is realized when a pilot starts the task close
to the edge of the back half on the assumption he will fly to one
tangent point and, because of a change in conditions, actually flies
to the other tangent point.

In a simple graphic analysis of the defined task I estimated a
distance of over 8 miles of start cylinder circumference between the
intersections of the two extreme case arcs and the start circle. *In
other words, the potential front half circumference of approx 31.4
miles is reduced to a no risk arc of approx 23.4 miles. Someone with a
greater enjoyment of math will come up with a more accurate answer.

How, with the proposed rule change, is the pilot expected to know
whether the selected start cylinder exit point will result in a
devalued first leg distance?

Andy

I had to read that one three times -- and get out my daughter's high-
school geometry textbook ;-)

I had a similar reaction - but without the analytic rigor. Andy, I
assume you were using the minimum first leg distance (is there a
minimum beyond the cylinders not touching?) coupled with the maximum
turn area radius (30 mi). It's a problem in that the acceptable start
locations are not defined until after a pilot starts, and even if it
were defined, it's hard for a pilot to know for certain if they are in
the "front half".

I am assuming that the problem this is designed to solve is the one of
pilots starting out the top near the back of the cylinder and bumping
gaggles on the way to the front. Maybe others have seen this happen
but I have not, and I can't imagine anyone starting out the back side
of the cylinder. So I wonder if it is worth the complexity to solve a
problem that may not exist - at least not to a significant extent.

9B

9B- Hide quoted text -

- Show quoted text

How do I "clearly" know where to turn in the turn area now?
Hmmmm.......need something with maybe a red arc in the turn area from
the start fix from where I started in start cylinder. This is what I
"clearly" need.
It would be to "easy" to have just a start circle with a max. start
height, since now we can exit anywhere along the side of the cylinder.
We had the exit out the top because of only one prime exit point and
that was to help spread out the folks. But now we can exit anywhere
along the radius of the cylinder, so why do we still need to exit out
the top???? Hmmmmmmmm......where's that brown cow.......

Thermal tight, Soar high, spend more money and look inside...........
711.

On Jan 6, 5:26*pm, wrote:

I had to read that one three times -- and get out my daughter's high-
school geometry textbook ;-)

And I thought you would be the one that provided the answer to 4
decimal places!

Andy

"Andy" wrote in message
...
On Jan 6, 5:26 pm, wrote:

I had to read that one three times -- and get out my daughter's high-
school geometry textbook ;-)

And I thought you would be the one that provided the answer to 4
decimal places!

Andy

If I read this correctly, the scored first leg distance is unknown until the
first turn is made? Still, one never really knows how far you will fly, so
does it matter? The object is to run out the clock, and you don't really
know how it will go till about half the flight, and you see the conditions
ahead.

The power of prophecy would be very handy.

Hartley Falbaum
USA "KF"

On Jan 7, 7:20*am, "HL Falbaum" wrote:

If I read this correctly, the scored first leg distance is unknown until the
first turn is made?

No, while that is true, it is not the point I wished to make.

To understand the issue you need a picture of the task I described
showing the tangent points and the arcs that intersect the start
cylinder. Since I can't provide that you will need to draw it
yourself.

The point I wished to make is that the area of the start cylinder that
will give full credit for first leg distance is dependent on the
position of the first turn area control fix (the pilot selected turn
point). Since the position of that control fix is unknown when the
start point is selected, the pilot takes a risk when starting in some
areas in the front half. The no risk area of the start cylinder is
not the "front half" but an area that may be considerably smaller than
the "front half". That no risk area is defined by the area of overlap
between the two arcs drawn from the turn area tangent points.

Note that no start penalty will show on the score sheet, you just lose
distance that you thought was part of your first leg. This makes it a
hidden penalty and most pilots would not even realize they had lost
points as a result of the chosen start point.

This will be of particular interest to SW pilots that often start out
of the top and needs to be understood by anyone flying at R9 Parowan
unless the proposed rule change is abandoned.


Andy

On Jan 6, 4:25*pm, Andy wrote:

In a simple graphic analysis of the defined task I estimated a
distance of over 8 miles of start cylinder circumference between the
intersections of the two extreme case arcs and the start circle. *In
other words, the potential front half circumference of approx 31.4
miles is reduced to a no risk arc of approx 23.4 miles.

Don't want to re-open this but just in case someone reads it later I
need to correct the numbers. I should have said:

"The potential front half circumference of 16.7 miles is reduced to a
no risk arc of approx 8.7 miles."

My error was caused by starting with the full circle circumference
instead of the half circle circumference. The numbers were fine tuned
by 9B later in the discussion.

Andy

On Jan 12, 3:45*pm, Andy wrote:

"The potential front half circumference of 16.7 miles is reduced to a
no risk arc of approx 8.7 miles."

I'm digging myself a big hole here, but did say I was math averse!

Should be 15.7 and 7.7 of course.

Do the benefits of "start anywhere" outweigh the disadvantages?