Turnpoint placement to support safer Tasking

[[email protected]]

It has been discussed that it is safest to prevent Out&Return/U-turn type tasks that have acute angles between legs.

Many turnpoint lists do not support this well because many of the turnpoints are not near another turnpoint to use for steering. So if you use the far out turnpoint and want to add a 90° turn, the next nearby turnpoint is really far, so it makes a huge impact to the task length.

I was thinking one solution might be to have turnpoints in pairs when possible. Maybe the ideal distance would be 10 to 20 miles to support a ~10 mile TAT turn area and a smaller one on the other.

Placing nearby and “perpendicular� to the home point would help most often to change Out & Return tasks to rectangular race tracks or bowties

I put some images here to illustrate the idea:
https://docs.google.com/presentation/d/1-9kS7KTO0-gZFoqaLCpWRbdOAp_EnsyeKSVGYYfU5kk/edit?usp=sharing

Related discussion “Task turn angles other than 180 degrees, when is it safe?�
https://groups.google.com/forum/?fromgroups#!topic/rec.aviation.soaring/lREopFrhl10

I think for the 30 mile radius TAT is it not needed so much. But this would help for AST, MAT and TATs.
Please share your thoughts and ideas, do you agree with 10-20 miles spacing? Maybe 8-12 miles would be good for closer in points.

Chris

[[email protected]]

Steering points seem like a good idea, but in reality, contestants often work a close in thermal then head for the turn. If needed, they often return right back to the known lift. This results in the very head on traffic we are trying to prevent. Years back, we had a fatal midair as both pilots were looking off their left wing, deciding exactly when to bank up and snap the picture. The exact details are not known, but it was believed they ended up one above the other. When one ship banked up to get the photo, his wing tip hit the cockpit of the other ship. The only answer is eyes out of the cockpit and head on a swivel!
JJ

[Sean Fidler]

And not allowing gliders to turn anywhere in the 1-mile MAT or assigned task turn point radius, which US rules allow and create chaos and unpredictability which will eventually cause an accident (and regularly creates close calls).

Example, glider A goes to the left edge and turns right 90. Glider B goes to the back edge and crosses glider A at a 90-degree angle and with 150 knots of closure while looking R to clear his turn R. Result, glider dust. I have witnessed this countless times. This is among the most pointless, dangerous and foolish rules in the US contest rules. Safety starts with smart rules. Allowing chaos in each turn area (MAT or AT) is not smart. It's quite dumb.

Of course, US unique (other countries refuse to use them) MAT tasks have gliders approaching the same turn from any angle occasionally, as well as finishing from numerous directions. Another prize of US rules stupidity. The MAT task should be immediately removed from the US rules for numerous reasons.

OK. I feel better now. Siiigh.

[Steve Koerner]

I agree with the original poster. Yes, more turnpoints are needed in contest databases. We are way past the point in time that we should have to support legacy computers with limited memory at the expense of everyone's safety. It is important that the angles be large.

Sean makes a very good point also. Let's get rid of the chaos inside the circles. Sean's concern seems to relate mostly to MAT tasks. I'd say the bigger worry is the chaos inside our area tasks. It occurs to me that there is a simple solution to that. Let's make the scored turning point the point at which you enter the turn area. This would still allow a large latitude of total distance, though a bit less than the turn-anywhere approach that exists in the present rules. If it's thought that we need to get back to the same amount of latitude (though I don't think we do) then the maximum circle might be allwed to be 35 miles or 40 miles. With everyone turning on the the circumference, we will all be able to fully anticipate the actions of their compadres and everyone nearby will assuredly be going the same direction around the task. It is far safer when we're all going the same direction.

[Tango Eight]

On Saturday, February 11, 2017 at 1:34:29 PM UTC-5, Steve Koerner wrote:
> I agree with the original poster. Yes, more turnpoints are needed in contest databases. We are way past the point in time that we should have to support legacy computers with limited memory at the expense of everyone's safety. It is important that the angles be large.
>
> Sean makes a very good point also. Let's get rid of the chaos inside the circles. Sean's concern seems to relate mostly to MAT tasks. I'd say the bigger worry is the chaos inside our area tasks. It occurs to me that there is a simple solution to that. Let's make the scored turning point the point at which you enter the turn area. This would still allow a large latitude of total distance, though a bit less than the turn-anywhere approach that exists in the present rules. If it's thought that we need to get back to the same amount of latitude (though I don't think we do) then the maximum circle might be allwed to be 35 miles or 40 miles. With everyone turning on the the circumference, we will all be able to fully anticipate the actions of their compadres and everyone nearby will assuredly be going the same direction around the task. It is far safer when we're all going the same direction.

"Chaos"? That's Sean playing an ******* marketing game where you plant seeds of doubt in the customer's mind about your competition with a nice, catchy, powerful key word. This is the same guy that claims that US start rules are dangerous. I suggest we give him all the attention he deserves here.... which is "none".

AAT is our best and most flexible task. Works as is.

-Evan Ludeman / T8

[[email protected]]

"Result, glider dust. Â*I have witnessed this countless times."

Sean, care to relay the dates, times and results of these "countless" midair collisions?

[Steve Koerner]

You're right Evan - the word "Chaos" overstates the issue. Yet crossing traffic is relatively hazardous. The more acute the angle, the more hazardous it is.

It turns out that a small revision to how we use turn areas will completely eliminate the crossing traffic problem. That's my point. The same idea applies to MAT and AST circles. Let's eliminate the crossing traffic in all turn circles please.

[[email protected]]

On Sunday, February 12, 2017 at 10:13:20 AM UTC-5, Tango Eight wrote:
> On Saturday, February 11, 2017 at 1:34:29 PM UTC-5, Steve Koerner wrote:
> > I agree with the original poster. Yes, more turnpoints are needed in contest databases. We are way past the point in time that we should have to support legacy computers with limited memory at the expense of everyone's safety. It is important that the angles be large.
> >
> > Sean makes a very good point also. Let's get rid of the chaos inside the circles. Sean's concern seems to relate mostly to MAT tasks. I'd say the bigger worry is the chaos inside our area tasks. It occurs to me that there is a simple solution to that. Let's make the scored turning point the point at which you enter the turn area. This would still allow a large latitude of total distance, though a bit less than the turn-anywhere approach that exists in the present rules. If it's thought that we need to get back to the same amount of latitude (though I don't think we do) then the maximum circle might be allwed to be 35 miles or 40 miles. With everyone turning on the the circumference, we will all be able to fully anticipate the actions of their compadres and everyone nearby will assuredly be going the same direction around the task. It is far safer when we're all going the same direction.
>
> "Chaos"? That's Sean playing an ******* marketing game where you plant seeds of doubt in the customer's mind about your competition with a nice, catchy, powerful key word. This is the same guy that claims that US start rules are dangerous. I suggest we give him all the attention he deserves here... which is "none".
>
> AAT is our best and most flexible task. Works as is.
>
> -Evan Ludeman / T8

Alternate facts.
So sad.
UH

[Steve Koerner]

I wish not to take away from the original poster's point about adding turnpoints to the database to facilitate wider turning angles. That is a very good point. I urge that idea to be followed as well. This past year, I complained to a CD about a task call with acute angles. They are dangerous.

[[email protected]]

On Sunday, February 12, 2017 at 10:49:58 AM UTC-5, Steve Koerner wrote:
> I wish not to take away from the original poster's point about adding turnpoints >to the database to facilitate wider turning angles. That is a very good point. >I urge that idea to be followed as well. This past year, I complained to a CD >about a task call with acute angles. They are dangerous.

Touching the perimeter might be better in some cases but requires a rule change to be most effective - and not necessarily my goal. [Or more accurately there is nothing to stop Sean or anyone else from touching the perimeter and leaving now.]
Even still that is not a full fix and would not be practical for larger TATs.
In the meantime I think additional turnpoints is relatively easy.

I would like to hear more feedback on if others agree this would help, how best to implement it, and any other changes to turnpoint files or tasking that would be better.

Thank you Steve for a valiant attempt to keep this thread on topic.

Chris