Race Replay: Abilyn vs. In Theory in the 2026 Bitter Ender Regatta

Abilyn (J/120) against In Theory (JPK 10.80), Oct. 17-18, 2026 during the LYC/STC Bitter Ender Regatta. In Theory started just after 1200, at the beginning of the starting window, which ran from 1200-1600. By contrast, Abilyn started at around 1500. In Theory’s track is shifted by approximately +3 hours so that, for purposes of this replay and visualization, both boats started at the same time—at 14:59:42 EDT.

Camera
Overlays
Click the map to pause or resume. Drag to pan. Pinch (or Ctrl/⌘ + scroll) zooms in small steps; double-click zooms in. Click the View options bar or the Live readouts panel to expand or collapse it; both start collapsed, and View options folds away when you press Play. The finish line runs 180°M from the pin (shown as 168°T).
Elapsed00:00:00
Distance ahead along the course, in nautical miles. Click or drag a chart to move through the race.
Sails carried, as reported by each crew. M is the mainsail and H is the headsail.
Difference is Abilyn minus In Theory, in knots. Blue favors Abilyn, orange favors In Theory.
Each row is one sail setup. Speeds also reflect wind, current and sea state, so they show what happened under each setup, not what the sails caused.
Abilyn polar performance by leg, from the Expedition log. In Theory has no polar data.
Course is the rhumb-line distance: start area to Mark 1 to Mark 2, then Mark 2 to the point where that boat crossed the finish line. Legs 1 and 2 are the same for both boats, and leg 3 differs because the boats crossed at different points. Sailed is the distance each boat actually covered. SOG is sailed distance over time. VMC is course distance over time.

The dashed lines through each boat are square to the rhumb line of the leg it is sailing (parallel to the finish line on leg 3). The lead is the distance between them, measured along that rhumb line, and the black bar on the map shows it. The distance to the next mark is the straight-line distance from each boat to that mark, or to the finish line on leg 3. It can differ from the lead because it does not use a fixed axis.

Polar % is Abilyn’s boat speed as a percentage of the polar target at the logged wind (the PolBsp% and TWS columns of the Expedition log extracts), so 100% means on polar. The 1-second samples are averaged into the same 5-second bins as the GPS tracks. Positions in the log match the GPX track to within 0.01 nm. The figure depends on the polar file and the boat-speed and wind calibration in Expedition, which I have not audited. In Theory has no equivalent, so polar % shows how Abilyn sailed against her own targets, not directly how she compared with In Theory.

Mark 1 is New Haven Harbor Lighted Whistle Buoy Nh (41°12.1248′N, 72°53.7836′W) and mark 2 is Old Field Point Gong Buoy 11a (40°59.2169′N, 73°7.289′W). Leg times run to each boat’s closest approach to a buoy; both boats passed within 0.05 nm of both. The finish line is the pin position and 180°M you gave, with 12°W variation assumed for the true bearing. The “Along the course” lead readout uses each boat’s distance to that line, so both boats reach zero at the finish.

Sail information comes from each crew’s recollection, not from the GPS files. Dashed outlines mark approximate times, hatching marks sails changed back and forth or during a window, and dotted outlines mark sails not stated by the crew that I assumed.

“Over ground” is distance sailed divided by time, measured from both tracks at the same 5-second spacing. Raw 1-second GPS jitter would otherwise inflate In Theory’s distance by about 1.4%. VMC is velocity made good on course: progress along the straight line to the next mark divided by time, so it discounts distance spent off that line. On the last leg the line runs from Mark 2 to the point where that boat crossed the finish line. It is measured along a fixed line for each leg, not toward a live bearing. “Along the course” in the lead readout projects each boat onto start, mark 1, mark 2 and the finish line and compares the two distances. No wind or current data is in these files.