Paul Remde wrote:

I must respectfully disagree. If we just use sunset as the end of soaring
flight that gives an unfair advantage to a pilot that is far from home or at
altitude when the sun sets. He/she should have planned ahead and landed on
time.

And exactly which time would that be, Paul?

You seem to have lost track of the story so far:
Doug wants to be able to pick illegal flights on OLC but he's having
trouble deciding which flights are illegal because he doesn't know when
it's "sunset" (as 'un'defined in the FARs) at all the places OLC flights
go to. Last night two astronomers locked horns and are heading for the
jugular over when sunset might be.

Now read on:

I know this won't help but in Oz the rules a
1. "Night" is the period between the end of evening civil twilight and
the beginning of morning civil twilight.
2. CASA (FAA equivalent) publishes beginning and end of daylight graphs
for latitudes from 0 to 45 throughout the year.
3. Daylight flight occurs between those times after converting local
time to Standard/Daylight Time.

Note that daylight "ceases" at a particular longitude solely dependent
on its latitude. No allowance for terrain, etc.

But the following is also in the AIP:
"Users ... should note that the parameters used in compiling the ...
Graphs do not include the nature of the terrain ... other than a
cloudless sky and unlimited visibility ... Consequently, the presence
of cloud cover, poor visibility or high terrain to the west of an
aerodrome will cause daylight to end ... earlier than that extracted
from the appropriate graph.
Allowance should made for these factors when planning a flight..."

The rules are reasonable but are no help in maintaining a level playing
field for a gliding competition.

So, Doug. Make up your mind what arbitrary rule you would like to
implement for the SSA-OLC and publish it. Let's say - evening civil
twilight at the latitude.

Stop using the FAA as an excuse and a crutch. Stand on your own feet.
Make a rule. Publish it. Enforce it. Cop the flak.

GC