That makes a lot of sense to me. Avenal is really just
flat fields everywhere. And I can see how deconflicting with other
traffic is important (although Minden seems pretty lightly
used for GA).

I guess remote cylinders or remote control points are
either not available to CDs or just not popular. 1000ft
seems like a lot of altitude to sort things out, so maybe this isn't
that critical, and at a huge airport like Avenal or Minden
(with lots of runways) it seems like there are still lots of options
even at low energy.

Thanks for the response!

In article ,
Marc Ramsey wrote:
Mark James Boyd wrote:
How many CDs choose cyclinders? Of theses cyclinders, how many
are centered at the airport, and how many are remote (centered away
from) the airport?

If remote, are they 2-5km out at 1000ft minimum? What is the
cylinder radius? Is it 1/2km like the previous poster's
"control point"?

A finish cylinder doesn't have to be remote, as you pull up at the edge,
not the center. If you need to keep high speed finishers away from the
airport, you increase the radius (up to a maximum of 4 miles) and raise
the floor.

I've flown in five sanctioned contests that used GPS finishes (I also
did the finish gate dance in pre-GPS days). Of those, four used finish
cylinders and one used a finish gate.

Out of the four cylinders, all were centered on the airport (at an
identifiable point, like a wind triangle), two (Montague and Tonopah)
used the standard 1 mile radius and 500 foot floor, the other two were
at Minden where a 2 mile radius and 1000 foot floor is used, to minimize
conflicts with non-contest traffic.

The finish gate was used at Avenal, the standard 1 km wide, adjacent and
running perpendicular to the center of the west side of the runway.

Marc


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Mark J. Boyd