This is an earlier experiment. Read the amendments below before treating its findings as current.
The question
Why are crossing-lane craft within reach 200–300 m before the crossing, and do they arrive before a craft turns away?
What was tested
No new runs: for each crossing passage, which came first, neighbour or turn; and each craft's time far off its lane.
What was found then
Where both happened, the neighbour came first in 75–88 % of passages, about 20 s before the turn, even with no crossing craft near at the start. Early neighbours were crossing-lane craft 258–307 m off their own lane, at the edge of its spread. With heading copying on, 10 % of ideal-craft (instant-response) positions are over 219 m off lane; with it off, 99 % are within about 89 m, and no early neighbour appeared in 23,500 passages. Most ideal craft (84–88 %) stray for about a minute, and nearly all wing craft stray. Whether craft react or pass the disturbance on stayed open.
What we learned later
Counting all passages, the neighbour came first in about 7 in 10 (68–73 %), and the 'one in twenty' share where the turn came first is not a hard minimum.
research/envelope.md:5229
Withdrawn: 'the wing turns before any neighbour arrives' (a mistake in the search window). There is no sideways wall in the code, so the 89 m is an observed spread, not a limit.
research/envelope.md:5152
Withdrawn: 'excursions mostly start in mid-flight'. About half follow the craft being put back at the lane start after reaching its end. Counted across those restarts, an excursion lasts 70–75 s (cycle 103).
research/envelope.md:4991; research/envelope.md:4940
What changed
Nothing.
Numbers and source references
- 75–88 %
- passages with both events where the neighbour came firstresearch/envelope.md:5229
- 20 s
- typical lead of the neighbour over the turn (17–22 s)research/envelope.md:5229
- 258–307 m
- median off-lane distance of early crossing-lane neighboursresearch/envelope.md:5152
- 219 m
- 90th percentile off-lane distance, ideal craft, copying onresearch/envelope.md:5152
- 89 m
- 99th percentile off-lane distance with copying offresearch/envelope.md:5152
- 23,500
- passages with copying off and no early neighbourresearch/envelope.md:5152
- 84–88 %
- ideal craft that spend time more than 200 m off laneresearch/envelope.md:5094
- about a minute
- typical excursion before returning (fragment median)research/envelope.md:5094
- 98–100 % / 28–49 %
- wing craft visiting the far-off-lane state / their median share of time thereresearch/envelope.md:5094