This is an earlier experiment. Read the amendments below before treating its findings as current.
The question
In a 9 m/s wind, above the wing's 8 m/s cruise, lanes ended far off. Why?
What was tested
Twelve layouts per setting at 9 and 5 m/s wind, wings and ideal craft (they respond instantly), some with a higher limit on the pull back toward the lane. Traces recorded heading and ground speed.
What was found then
In 9 m/s wind the fleet is carried sideways: about 370 m off on lanes with a gentle crosswind, 2.5–2.7 km with a strong one. Craft have no drift correction, and the limited pull can ask for only about 2.6 m/s sideways. A higher limit shrinks offsets but adds close-call time. The into-wind lane barely moves forward. At 5 m/s wind, strong-crosswind lanes are still lost and gentle ones sit about 150 m off; ideal craft sit 40–100 m closer. The limit alone does not explain the gentle lanes.
What we learned later
The 2.6 m/s is a limit on what the lane rule asks for, not on the actual sideways speed; speed-matching also adds sideways push.
research/reviews/brief-c55.md
Ideal craft also use the speed-matching rule, so its part in the offsets was left open, not ruled out.
research/reviews/brief-c56.md
What changed
Nothing.
Numbers and source references
- 12
- seeds per fleet settingresearch/reviews/brief-c54.md
- ~370 m / 2.5–2.7 km
- late offset, 3.1 / 8.5 m/s crosswind lanes, 9 m/s windresearch/reviews/brief-c53.md
- 2.64 m/s
- sideways command allowed by the capped pull-backresearch/reviews/brief-c54.md
- 2.6 → 2.0 → 1.7 km
- strong-crosswind offsets, cap 0.35 / 0.7 / 1.0 of cruiseresearch/reviews/brief-c54.md
- +25 % / +45 %
- near-miss time with the raised caps (6.84 → 8.58 / 9.92)research/reviews/brief-c54.md
- 3.6 m/s; 55 %
- against-wind ground speed; late samples losing groundresearch/reviews/brief-c55.md
- 1.3–1.4 km; 148–158 m
- 5 m/s wind: strong-crosswind lanes; gentle lanes, wingresearch/reviews/brief-c55.md
- 109–110 m
- gentle lanes, reference craft, 5 m/sresearch/reviews/brief-c56.md