Maryland School of Sailing · vídeo

Qué cubre este vídeo

A paddlewheel speed sensor on an Island Packet 40 named Navigator read 15 percent high, confirmed by a calibration run on the Chester River in October 2020.2:23 Tom Tursi describes a 10-step procedure for measuring and correcting a boat's water speed and distance instruments using two fixed navigation aids rather than floating buoys.0:45 The measured course ran 0.6 nautical miles between Channel Junction Light LC and Green dayboard G1 on bearings of 276° and 096° true, oriented perpendicular to current flow to minimize current error.4:56 The crew motored at 2,400 rpm, timed each leg with a stopwatch, and computed speed over ground by dividing chart distance by elapsed time.6:58 Dividing SOG by indicated water speed yielded a speed correction factor of 0.85 outbound and 0.86 return, averaging 0.855.10:15 Because the same paddlewheel drives both speed and distance readouts, the distance correction factor equals the speed factor.11:17 Five runs across multiple cruises produced correction factors of 0.85–0.88, and applying the factor to dead reckoning plots and running fixes improved consistency over uncorrected readings.12:19 The procedure also covers TVMDC compass conversion, use of the US Coast Guard light list to calculate inter-NAVAID distance, and the critical distinction between water-referenced speed and GPS ground speed.5:29

Barcos en este vídeo

Más de Maryland School of Sailing

Chat 21 - Updates to Crew Overboard Techniques and Equipmentsept 2026Captains Tursi and Mummert Answer Questions Posed By Participantsago 2026Classic Navigation In The Modern Worldago 2026Ocean Passage Wrap Upago 2026

De Maryland School of Sailing — mira el barco del canal, la tripulación y cada vídeo analizado.

The Sailing Directory Newsletter

Un correo electrónico con los mejores hallazgos de la flota: los momentos, barcos e historias que merecen tu tiempo de visionado. Introduce tu dirección para recibir tu propia copia.