Pensacola · 2026-11-08

• Race Team's tacks were the best in their band. At 20-22.5 km/h Race Team made 25.6 km/h through (18 tacks), against 24.9 for AUS (Valencia Fri), the best tacker that day, and 22.5 for NZL (Valencia Fri) (12). At 22.5-25 it made 26.8 (4), against 21.6-25.1 for the Halifax boats. It touched down once in 39 tacks at 12.5-25 km/h. NZL touched down in 3 of 44 at Valencia Fri and 9 of 26 at Valencia Sat. In Block 3's light air (12.5-15) the boat stayed on the foils through every tack: 32.4 km/h at the lowest against 21.9 for NZL (Valencia Sat), and level on VMG through (17.8 against 18.0).
• Against NZL's 10 best tacks at Valencia Fri, Race Team turns more slowly and keeps less speed. At 20-22.5 km/h Race Team's peak yaw rate was 23 deg/s against 29, its peak rudder 12.1 deg against 14.1, its lowest speed 31.3-31.8 km/h against 34.1, and 37.3-37.9 at +10 s against 40.3. Measured from the middle of the heading change, the down button and the wing invert came at the same moments: down button -4.0 and -3.8 s against -4.0, invert -0.1 and +0.3 against -0.1. The old board went up 0.6-0.8 s sooner (+1.4 to +1.6 against +2.2 s), and the new board carried 1.0-1.6 deg more rake input at T = 0 (1.8-2.4 against 0.8). Race Team still made more VMG through (25.7 and 25.5 against 23.4), the same share of its own straight-line VMG (75 % against 76 %). The speed NZL's best carry through the turn, 2.5-3 km/h more, is where the next gain is.
• Race Team's best tacks went in fast, used less rudder, and kept both hulls up. At 20-22.5 km/h only 4 tacks were good (80 % or more of straight-line VMG, no hull under 400 mm), so treat this as a pointer. They went in at 49.4 km/h against 47.7 for the other 14 and peaked at 10.2 deg of rudder against 12.5. The outside hull peaked at 1,448 mm against 1,358, the lowest hull stayed at 669 against 455, and they spent 2.2 s on two boards against 3.0. They came out at 38.6 km/h at +10 s against 36.6, for 28.3 km/h through against 24.9. Across the day 7 of the 9 good tacks came in Block 2, six of them Port to Stbd.
• Port to Stbd was a little better: 26.5 km/h through against 25.2 at 20-22.5 (77 % against 74 % of straight-line VMG). On the corrected wind the gap is half what it read before. The boards and the wing were timed the same both ways. As on 7 Nov, the starboard hull flew higher on Port to Stbd (1,455 against 1,260 mm) and the boat heeled more (3.4 against 1.7 deg). In Block 3 the two were level (17.3 and 17.7).
• Hedging: the data agree that a low inside hull slows the lock. They don't show that turning up early causes it, and today it didn't cost. In Blocks 1 and 2 the 12 tacks that turned most before the new board locked (24 deg of heading against 15) took 3.1 s from the down button to the lock against 2.4. Their inside hull was 184 mm lower at the lock (1,008 against 1,192). But they turned more slowly in the first second after the button (3.8 against 4.2 deg/s), and their inside hull was already 79 mm lower at the button. Those tacks were no worse: 26.3 km/h through against 25.7, with less outside-hull flare (1,326 against 1,406 mm). The day's two best tacks, 08:53:28 and 08:45:43, were among the four that turned most before the lock (34 and 32 deg). In Block 3's lighter air the two groups were close (17.3 and 17.7 km/h through, 6 tacks each).
• Upwind on the small jib, Race Team J2 and Jake FC beat every Valencia Fri boat. Race Team J2 at 20-22.5 km/h sailed 41.5 deg at 47.5 km/h, for 36.1 km/h of VMG (26 periods). NZL (Valencia Fri) sailed 42.7 deg at 45.3 km/h (33.3), DEN (Valencia Fri), the best upwind after NZL that day, 38.5 at 43.7 (34.3), and AUS (Valencia Fri) 40.8 at 45.1 (33.9). Jake FC at 17.5-20 sailed 41.6 deg at 46.3 km/h (35.1, 20 periods), about 3 deg higher than NZL, DEN and AUS (Valencia Fri) at the same speed (33.2-33.3). Jake on the wing sailed 2-3 deg lower than them at 17.5-20 (47.0 deg) with only 1 km/h more speed, and made 32.5.
• Downwind, B15 was 2-4 km/h of VMG behind NZL and AUS (Valencia Fri) at 17.5-22.5, and its wing was set up differently. At 17.5-20, Race Team J1 sailed 147.1 deg at 52.4 km/h (44.8), Jake FC 144.0 at 54.8 (44.6) and Jake on the wing 139.2 at 55.9 (43.2). NZL (Valencia Fri) sailed 142.6 at 58.4 (46.7) and AUS (Valencia Fri) 146.7 at 56.5 (47.6). Only Race Team J2 at 20-22.5 was level with NZL (49.8 against 49.1). B15 carried 14.2-18.2 deg of wing rotation and 16.5-19.5 deg of twist, with CA6 not inverted (+4 to +7). The Valencia Fri boats had 10.5-13.7 deg of rotation, 23.5-28.8 of twist and CA6 inverted (-8 to -1). Race Team J1's own fast quarter downwind had more twist (19.2 against 11.5 deg) and a lower CA6 (+1.5 against +14.3). Blair's dive sets out the numbers to test.
• The big jib wasn't quicker than the small one today, but it only had 7-11 periods where they overlap. At 20-22.5 km/h, the one band with enough of both, Race Team J2 made 36.1 km/h of VMG upwind against 35.1 for J1 (26 and 11 periods). Downwind it made 49.8 against 46.6 (16 and 7). J1 sailed only in the first block, and below 17.5 km/h it was mostly off the foils at the start. The expected J1 gain above 15 km/h needs the two jibs back to back in the same breeze.

Read these before trusting a gap.

• B15's wind is corrected. In the same minutes, port read 11.5 deg more TWA upwind than starboard, and 1.3 deg less downwind, with boat speed and wind speed equal. A boat really sailing 11 deg lower would be several km/h faster, so it was the wind gear. Every wind channel was corrected before the app's pipeline: TWA and TWD by +5.75 deg upwind and -0.75 downwind, AWA and AWA-E1 by +1.6, and VMG worked out again. Port and starboard now agree to 0.0 deg upwind and 0.2 downwind. A single TWD offset couldn't do it: the best one left a 6 deg split upwind or downwind (Deep dives).
• What the correction changed. Before it, port's upwind VMG read about 4.5 km/h low, so the bar threw out port periods: 82 port and 128 starboard kept upwind. Now it's 116 port and 94 starboard, and the total is the same, because the bar always keeps a column's better sailing. The tables are now fair as built, so the commentary quotes them directly. T = 0 now falls at the same point of the turn on both tacks, where before it was 0.8 s apart.
• The correction is least certain in Block 3's light air (12.5-15 km/h), which had only 3 same-minute windows with both tacks.
• The reference boats' own sensors aren't corrected. Their tack mix moves them by up to about 1 km/h of VMG (AUS at Valencia Fri, 20-22.5).
• Clear air: our teams sailed alone. The reference days were racing: Valencia Fri (practice racing) and Sat had six races each (NZL in 2 and 3), and Halifax five (NZL in 2). Level numbers are encouraging, but they don't prove anything in traffic.
• Halifax was much windier (median 23.5 km/h), so it only meets today at 17.5-25 km/h. Valencia Sat was the light day (median 15.3).
• How the numbers are built: each column is the average of its own better sailing, at or above 95 % of its own median VMG, with periods trading speed for angle left out. A tack counts when it keeps 65 % of its crew's straight-line VMG and a gybe 70 %. BRA is left out of every comparison.

• 08:53:28 (14:53:28 UTC) Race Team, Port to Stbd: the best tack at 20-22.5 km/h, 29.4 km/h through (86 % of straight-line VMG), lowest hull 910 mm, 34 deg turned before the lock
• 08:45:43 (14:45:43 UTC) Race Team, Port to Stbd: 26.8 km/h through in 25.5 km/h of wind (84 %), 32 deg turned before the lock, 3.6 s from button to lock
• 08:48:22 (14:48:22 UTC) Race Team, Port to Stbd: 28.4 km/h through, neither hull under 845 mm
• 08:46:25 (14:46:25 UTC) Race Team, Stbd to Port: the best Stbd to Port tack in breeze, 28.3 km/h through (83 %)
• 08:54:06 (14:54:06 UTC) Race Team, Stbd to Port: a hull to 204 mm with 14.8 deg of rudder, 24.1 km/h through
• 08:58:12 (14:58:12 UTC) Race Team, Port to Stbd: the day's touchdown. The down button came 10.1 s before T = 0, the board took 7.1 s to lock, and the inside hull was at 237 mm when it did
• 09:03:46 (15:03:46 UTC) Race Team, Port to Stbd: came in from a reach (144 deg), 19.5 km/h through
• 08:54:58 (14:54:58 UTC) Race Team, Port to Stbd: the outside hull to 1,653 mm, the highest of Race Team's day, 28.3 km/h through (83 %)
• 10:25:29 (16:25:29 UTC) Race Team, Port to Stbd: the best light-air tack, 21.5 km/h through in 14.2 km/h of wind (89 %), 0.5 deg of heel
• 10:29:51 (16:29:51 UTC) Race Team, Port to Stbd: bore away to 86 deg after the tack
• 08:08:40 and 08:09:59 (14:08:40 and 14:09:59 UTC) Race Team: the first two tacks, in 11-12 km/h, came off the foils

On the small jib, Race Team J2 and Jake FC beat every Valencia Fri boat. Elsewhere B15 was level with the references or a little behind. B15's wind is corrected (Deep dives), so these are the tables' own numbers.

• 20-22.5, small jib: Race Team J2 sailed 41.5 deg at 47.5 km/h, for 36.1 km/h of VMG (26 periods). NZL (Valencia Fri) sailed 42.7 deg at 45.3 km/h (33.3), DEN (Valencia Fri) 38.5 at 43.7 (34.3) and AUS (Valencia Fri) 40.8 at 45.1 (33.9). Race Team J2 was 1.2 deg higher than NZL and 2.2 km/h faster. Jake FC sailed 43.7 deg at 46.6 km/h (34.4, 20 periods): 1.1 ahead of NZL (Valencia Fri) and level with DEN and AUS.
• 20-22.5, big jib: Race Team J1 sailed 41.3 deg at 47.0 km/h (35.1, 11 periods). AUS (Halifax) sailed 42.7 deg at 47.9 km/h (36.1) and SWE (Halifax), the best upwind that day, 35.9 at 44.5 (36.0). NZL (Halifax) sailed 48.5 at 49.2 (32.2).
• 22.5-25: Race Team J2 sailed 42.0 deg at 47.0 km/h (36.5, 8 periods). Only the big-jib Halifax boats were here: NZL 34.4, SWE 38.0 and AUS 39.0.
• 17.5-20, big jib: Race Team J1 sailed 43.3 deg at 46.6 km/h (35.5, 8 periods), against 39.7 deg at 44.7 km/h (34.5) for SWE (Halifax).
• 17.5-20, small jib: Jake FC sailed 41.6 deg at 46.3 km/h (35.1, 20 periods). NZL, DEN and AUS (Valencia Fri) sailed 44.4-45.0 deg at 45.9-46.6 km/h (33.2-33.3), so Jake FC was about 3 deg higher at the same speed. Jake on the wing sailed 47.0 deg at 47.4 km/h (32.5, 23 periods): 2-3 deg lower with about 1 km/h more speed, 0.7-0.8 behind.
• 15-17.5: Jake on the wing sailed 48.6 deg at 46.6 km/h (30.8, 28 periods) and Race Team J2 49.9 at 42.5 (28.4, 9). On the small jib, NZL (Valencia Fri) sailed 40.2 deg at 44.8 km/h (35.0, 13 of 14 periods on port) and AUS (Valencia Fri) 49.2 at 48.0 (31.9). The big-jib Valencia Sat boats made 25.8 in light racing.
• 12.5-15: Race Team J2 sailed 54.7 deg at 44.1 km/h (26.5, 26 periods). AUS (Valencia Sat) sailed 53.3 at 41.8 (25.8). NZL (Valencia Sat) sailed 44.9 at 43.3 (32.4), all 9 periods on port.

How steady the boat was (ride-height and heel deviation inside each 6 s period). At 20-22.5 km/h Race Team J1 had 70 mm and 0.7 deg, Race Team J2 72 and 0.6, and Jake FC 93 and 0.8. The references had 55-83 mm and 0.6. At 15-17.5 Race Team J2 had 53 mm and 0.5 deg, and Jake on the wing 73 and 0.8, against 56-76 mm and 0.4-0.6 for the references.

What differs on the same wing, boards and rudders (the settings table is below):

• Jib lead was 57-81 % on our columns at 17.5-25 km/h, against 40-67 % for the references. That's the same gap as on 6 and 7 Nov.
• Jib sheet: the big jib was eased 32-36 % against 16-19 % for the small jib on B15. The big-jib references at Halifax were 17-27 %.
• Wing: at 20-22.5 rotation was 9.5-10.4 deg, like the references' 8.4-10.9. Twist was 29.7-32.6 deg and CA6 -13 to -16, against 25.3-33.3 and -8 to -15. Rotation and AWA-E1 are in Blair's dive.
• Leeward cant: each column's fast quarter carried 3-6 deg more cant than its slow quarter, as on 7 Nov (Deep dives).

Downwind B15 was 2-4 km/h of VMG behind NZL and AUS (Valencia Fri) at 17.5-22.5 km/h. Only Race Team J2 at 20-22.5 was level, and the big jib was level or ahead in the light air.

• 12.5-15, big jib: Race Team J1 sailed 134.6 deg at 47.0 km/h, for 32.4 km/h of VMG (14 periods). That was level with AUS (Valencia Sat), at 133.2 deg and 45.9 km/h (32.1). It was ahead of NZL (Valencia Sat), at 130.0 deg and 45.9 km/h (30.7): 4.6 deg deeper at a little more speed.
• 15-17.5: Race Team J1 sailed 139.2 deg at 46.8 km/h (35.6, 11 periods), level with NZL and AUS (Valencia Sat) (35.6-36.2). Jake on the wing sailed 138.8 deg at 55.4 km/h (42.2, 7 periods), against 43.5 for NZL and 45.4 for AUS (Valencia Fri).
• 17.5-20: Race Team J1 (big jib) sailed 147.1 deg at 52.4 km/h (44.8, 15 periods). Jake FC sailed 144.0 at 54.8 (44.6, 10) and Jake on the wing 139.2 at 55.9 (43.2, 10). On the small jib, NZL (Valencia Fri) sailed 142.6 deg at 58.4 km/h (46.7), AUS (Valencia Fri) 146.7 at 56.5 (47.6) and CAN (Valencia Fri), the best downwind after NZL that day, 141.1 at 56.6 (44.0). So our small-jib teams were 0.6-3.6 km/h slower through the water than NZL and AUS at a similar angle, and 2-4 km/h of VMG behind. Jake on the wing sailed 3.4 deg higher than NZL. Race Team J1 was as deep as AUS but 4 km/h slower.
• 20-22.5: Race Team J2 sailed 150.4 deg at 57.2 km/h (49.8, 16 periods), level with NZL (Valencia Fri) at 148.0 and 58.0 (49.1). Race Team J1 sailed 150.9 at 53.5 (46.6, 7) and Jake FC 148.8 at 54.4 (46.4, 18), both 2.5-2.7 behind NZL.

How steady the boat was at 17.5-20: ride-height deviation was 70 mm for Race Team J1, 72 for J2, 92 for Jake FC and 81 for Jake on the wing, against 98-118 for the Valencia boats. Heel deviation was 0.4-0.9 deg against 0.6-0.7. B15 sailed alone, and the references were racing.

What differs at 17.5-20 (the settings table is below):

• The wing is the biggest difference. B15 carried 14.2-18.2 deg of rotation against 10.5-13.7. Twist was 16.5-19.5 deg against 23.5-28.8 (Race Team J2's 5 periods: 26.4). CA6 was +4 to +7, not inverted, against -8 to -1, and CA1 22.1-23.7 against 20.1-22.8. AWA-E1 read -3.8 to +0.4 against 2.9-7.1. Every team's fast quarter on 7 Nov, and Race Team J1's today, had more twist and a lower CA6 (Deep dives, and Blair's dive).
• Jib sheet was eased 25-41 % against 20-34, and the lead set at 72-80 % against 61-69.
• Clew was nearer the centre: -120 to +126 mm against -88 to -244 (+ = leeward).

No starts today, so there are no reaches. A reach is only start line to M1.

Every turn is measured from T = 0, the moment the heading passes through the turn's own mean TWD (+ 180 on a gybe). The mean is TWD over 10 s either side of the app's TWA crossing, as long on each tack, so a wind sensor that reads the two tacks differently cancels out of it. That covers the tables, tracks, time series, the wing invert and the deep dives, and the app now uses the same T = 0. Each track is drawn to its turn's own wind, so every track points straight up the page at T = 0. T = 0 comes 0.3-1.0 s before the TWA crossing on tacks and 0.2-1.9 s on gybes, and within 0.2 s of the zero in the 6 and 7 Nov reports, so board and wing times read as they did there. On Race Team's tacks it falls within 0.1 s of the middle of the heading change on both directions. A tack counts when it keeps at least 65 % of its crew's straight-line VMG and a gybe 70 %. Race Team's tacks and gybes are one column, both jibs pooled. With BRA left out, ESP was the best tacker at Valencia Sat and Halifax and AUS at Valencia Fri. SWE, DEN and AUS were the best gybing boats.

Tacks at 20-22.5 km/h: Race Team was the best in the band. It made 25.6 km/h through (18 tacks), against 24.9 for AUS (Valencia Fri) (7), 23.5 for ESP (Halifax) (2) and 22.5 for NZL (Valencia Fri) (12). It went in at 48.0 km/h and held 31.7 at the lowest, within the references' 30.9-33.8. It turned more slowly: 6.5 s from 10 to 90 % of the heading change against 4.0-4.8, a peak yaw rate of 22.8 deg/s against 23.4-28.3, and 3.0 s on two boards against 4.0-5.0. Jake FC made 23.5 (4).

22.5-25: Race Team made 26.8 km/h through (4), against 21.6-25.1 for NZL, ESP and AUS (Halifax), 2 tacks each.

17.5-20: Jake FC made 23.7 (6) and Jake on the wing 21.7 (5). The references made 22.8 (ESP, Halifax), 22.4 (ESP, Valencia Sat), 21.9 (NZL, Valencia Fri, 8) and 21.6 (AUS, Valencia Fri, 14).

15-17.5: Jake on the wing made 21.3 (7) and Race Team 18.2 (2), against 18.6-18.7 for NZL and ESP (Valencia Sat) and 16.6 for AUS (Valencia Sat).

12.5-15 (Block 3): Race Team made 17.8 (9), against 18.0 for NZL (Valencia Sat) (6), 17.0 for AUS and 16.8 for ESP. Race Team stayed on the foils (lowest 32.4 km/h, lowest hull 639 mm). The Valencia Sat boats came off (20.9-29.1 km/h at the lowest, 17-33 % touchdowns), so their light-air tacks aren't a like-for-like target.

Touchdowns at 12.5-25 km/h (every tack, kept or not): Race Team touched down in 1 of 39 tacks (08:58:12, 14:58:12 UTC), Jake FC 0 of 11 and Jake on the wing 0 of 19. NZL touched down in 3 of 44 at Valencia Fri, 9 of 26 at Valencia Sat and 0 of 10 at Halifax. AUS had 3-7 at each.

Gybes at 20-22.5: Race Team made 43.4 km/h through (10). That was level with AUS (Halifax) at 44.1 (5) and DEN (Halifax), the best gybing boat there, at 43.6 (3). It was ahead of NZL (Valencia Fri) at 41.7 (3); Jake FC made 41.0 (4). At 22.5-25 Race Team made 47.9 (3), against 48.5 for NZL (Halifax) (4) and 49.8 for DEN (Halifax) (3). Those three came 18-20 s apart at 08:44 (14:44 UTC) and turned only 51-65 deg, so they are linked turns more than clean gybes. They only just clear the 50 deg real-turn rule now that the heading change is read from the new T = 0, so treat that cell as a pointer. At 17.5-20 Race Team made 40.4 (7), against 40.9 for NZL (Valencia Fri) (15) and 39.0 for AUS (18). Jake FC made 37.7 (4) and Jake on the wing 35.0 (5). At 12.5-17.5 Race Team made 30.4-34.0 and Jake on the wing 38.3, against 24-36. Jake on the wing came out of its gybes with 20.5-23.8 deg of wing rotation at +10 s (Jake FC 21.8 at 20-22.5), against 15.1-18.4 for Race Team and 11-18 for the references (NZL's two Halifax gybes at 20-22.5 had 20.9). That's the same high rotation as in its straight-line sailing downwind (Blair's dive).

No starts or course today: training sessions only.

No course marks today.

The day. This morning every 2026 calendar day was searched for the 27.5 m wing, LAB2 boards and LARW rudders. The coach chose Valencia Fri 4 and Sat 5 Sep and Halifax Sun 21 Jun. Valencia Thu 3 Sep is left out because it was on the 24 m wing. The coach gave the jib for each: small (J2) on Valencia Fri, big (J1) on Valencia Sat and at Halifax.

Rudders checked independently of the setup channel. Rudder rake at the same pitch separates the rudders. Foiling at 15-22.5 km/h, B15 sat inside each reference fleet:

HSRW reads 5.1-5.9 upwind (Sassnitz, 7 Nov), so these are LARW.

Five columns. Race Team's straight line is split by jib: Race Team J1 (07:58-08:32) is read against Valencia Sat and Halifax, and Race Team J2 (08:40-09:05 and 10:20-10:31) against Valencia Fri. Jake FC and Jake on the wing were both on the small jib. The coach asked for the tacks to be pooled across the jib change, so Race Team's tacks and gybes are one column.

B15's wind is corrected before anything is worked out (next dive). The reference boats are as their sensors read.

One rule, with each boat's own bar.

• Periods: foiling for the tables, wing set (camber at least 15 deg), and not within 10 s of a turn.
• Speed for angle: periods where boat speed fell over 1 km/h inside the 6 s while turning up (upwind) or bearing away (downwind) are left out.
• Each boat's bar: a period must be at or above 95 % of that boat's or column's own median VMG in that band. The figures are averages of what clears it.
• Manoeuvres: away from marks, real turns only. A tack counts when its VMG through is at least 65 % of its crew's straight-line VMG (same band and point of sail), a gybe at 70 %. They are medians.
• The turn's zero (T = 0) is the moment the heading passes through the turn's own mean TWD (+ 180 on a gybe), interpolated between samples. The mean is TWD over 10 s either side of the app's TWA crossing, so both tacks count alike.

Best boat. It's the best average VMG with the wind taken out, weighted by how much of today's sailing was in each band. BRA is never a comparison boat. NZL was first upwind and downwind at Valencia Fri, so the next boat is shown as the best. AUS is shown wherever it isn't best. A boat must cover at least half of today's sailing to be called the best. Valencia Sat's light air didn't, so no best boat is named there for the straight line, and neither is one for Halifax downwind.

B15 sails alone, so its wind gear can only be checked against itself. In the same few minutes the boat sails the same true wind angle on both tacks, so port and starboard should read alike. Today they didn't: port read 11.5 deg more TWA upwind than starboard, and 1.3 deg less downwind. AWA read 3.2-3.4 deg more on port. Boat speed and wind speed were the same on both tacks. A boat really sailing 11 deg lower would be several km/h faster, so this is the wind gear, not the sailing. (The split moves day to day: +4.1 deg on 6 Nov, -6.0 on 7 Nov.)

Why not one TWD offset. A single TWD offset turns the wind the same way on both points of sail, but the error ran opposite ways upwind and downwind. An offset on AWA alone fixes the angles but invents a wind-speed split that isn't in the data. Each was fitted to the 0.5 s straight-line foiling data, port against starboard in the same 4-minute windows (24 windows upwind, 18 downwind):

The correction blends linearly between 75 and 120 deg of TWA. AWA and AWA-E1 get +1.6 deg, which takes their split to 0.1 upwind and 0.2 downwind. VMG is worked out again from the corrected TWA (B15's VMG is boat speed x cos TWA), and wind speed is left as it read. It's applied to the raw data before the app's pipeline (config.WIND_FIX). So periods, the bar, manoeuvres, the turn tracks and T = 0 all come from the corrected wind.

After the correction, period by period (port minus starboard, each period against the other tack's within 4 minutes):

What it changed.

• Periods by tack. Upwind, the bar kept 82 port and 128 starboard periods before and keeps 116 and 94 now. Port's VMG had read about 4.5 km/h low, so the bar was throwing out good port sailing. The total kept stays at 385 of 765. The bar always keeps each column's better sailing, so a fair correction moves periods between the tacks rather than adding them.
• The tables are fair as built, so the commentary no longer needs to average the two tacks. Race Team J2 at 20-22.5 km/h reads 36.1 km/h of VMG, where it read 37.4 as built and 36.4 averaged over the tacks before the correction.
• T = 0. Before the correction, the TWA crossing fell 1.2 s after the middle of the heading change on Port to Stbd and 0.4 s after on Stbd to Port. That 0.8 s was all of the apparent timing difference between directions. T = 0 is now the heading through the turn's own mean TWD, which has both tacks in its wind, and it falls 0.0-0.1 s from the middle of the heading change on both directions.
• Least certain in Block 3's light air. Only 3 same-minute windows had both tacks there, and they suggest a smaller error than in breeze.

Get the wind gear checked before the next day.

Comparing a team with itself takes the setup out. These use each column's foiling periods with speed-for-angle periods left out and no bar, because a bar would remove the slow ones. They compare the fast quarter with the slow quarter at the same angle, with the wind taken out, as averages.

Upwind, all three columns with enough periods tell 7 Nov's story about cant again. Each fast quarter carried 3-6 deg more leeward cant than its slow quarter (-2.3 to +0.6 against +3.4 to +4.0), and less jib sheet eased (15-19 % against 22-24 %). It flew the leeward hull higher (1,080-1,154 mm against 900-1,080) with a little less rudder rake (3.4-3.6 against 3.8-3.9 deg). Race Team J2's fast quarter also had much more twist (33.1 against 27.3 deg) and a more inverted CA6 (-15.9 against -9.5).

Downwind, Race Team J1's fast quarter had much more twist (19.2 against 11.5 deg) and a lower CA6 (+1.5 against +14.3), the same as every team's fast quarter on 7 Nov. That points the same way as the fleet's downwind wing setup (Blair's dive).

Each pair sat in the same wind to within 1 km/h. Load follows speed, so the sheet and cunningham loads may be the result rather than the cause. Cant and twist are the settings to test on purpose.

Each column's periods above its own bar, with the wind taken out.

Upwind, Race Team J1 was 0.7 km/h of VMG ahead, Jake FC 0.6 ahead, Jake on the wing level and Race Team J2 0.6 behind. Downwind, Race Team J2 was 2.9 ahead, Jake on the wing level, Jake FC 0.6 behind and Race Team J1 0.9 behind. Race Team was steadiest on the rudder downwind, with 0.65-0.71 deg of movement inside a period against 0.74 for Jake FC and 0.95 for Jake on the wing.

A spell counts when the boat was sailing upwind with the wing set and either both hulls were under 400 mm or a hull was under 200 mm for over 3 s. Race Team J1 had 21 spells (282 s), 4 near a turn, in a median 12.9 km/h of wind. That was the light start of Block 1, where half its upwind time at 12.5-15 km/h was in H1. Every other column had 3 spells (21.5-29 s). Above 15 km/h every column foiled 90 % or more of its upwind time.

Every one of Race Team's 42 tacks, timed from T = 0 (the heading through the tack's own mean TWD) on the corrected wind. Outside and inside hull, rake input and measured rake on both boards, and cant are 5 Hz data. Yaw, rudder and heel come from the app's 0.5 s data. Block 1 (07:58-08:32) was on the big jib, and Blocks 2 (08:40-09:05) and 3 (10:20-10:31) on the small jib. The jib changes the straight line, not the turn, so the tacks are pooled where the wind is the same. Blocks 1 and 2 were at 17.5-25 km/h and Block 3 at 12.5-17.5, so those are kept apart.

How each tack is judged: by VMG through it (distance made to windward over -10 to +15 s) as a share of Race Team's own straight-line VMG in the same wind band. That's the measure behind the 65 % rule. Good is 80 % or more with no hull under 400 mm. Poor is under 70 %, or a hull under 300 mm. 9 were good, 22 OK and 6 poor. Four came off the foils: the first two in 11-12 km/h, 08:28:12 at 18 km/h, and the touchdown at 08:58:12. One bore away afterwards.

• Block 2 had the run. Seven of the 9 good tacks came between 08:45:43 and 08:54:58, six of them Port to Stbd.
• The poor ones were 09:03:46 (in from a reach at 141 deg), 08:54:06 (a hull to 204 mm with 14.8 deg of rudder), and four in Block 3's lighter air (63-69 %).
• The touchdown, 08:58:12 (14:58:12 UTC): the down button came 10.1 s before T = 0. The board took 7.1 s to lock, the inside hull was at 237 mm when it did, and the boat fell to 20.6 km/h.

What the good tacks at 20-22.5 km/h had in common. There were only 4 of them, against the other 14 in the same band, so treat this as a pointer:

• They went in faster (49.4 against 47.7 km/h) and used less rudder (10.2 against 12.5 deg at the peak). The peak yaw rate was about the same (22.2 against 22.8 deg/s), so the boat turned as quickly on less helm.
• The outside hull flew higher at the peak (1,448 against 1,358 mm). Both hulls stayed higher afterwards: lowest hull 669 against 455 mm, and the inside hull lowest 702 against 458.
• They spent less time on two boards (2.2 against 3.0 s). From T = 0, the down button came 0.5 s later (-3.6 against -4.1 s) and the board locked 0.3 s later (-0.9 against -1.2). The up button was the same (+1.6 against +1.5 s).
• They came out quicker: 38.6 against 36.6 km/h at +10 s. Three of the four were Port to Stbd.

Every tack: