Course Theorem (Sailing)
Description
This applet visualizes how sail courses which maximize the speed of a sailcraft or its progress towards a direction are related to the efficiency of the sailcraft, which can be expressed in terms of the apparent wind angle (AWA or beta).
The apparent wind angle (AWA) can be less than 20° for foiling racing boats:
https://www.nauticed.org/sailing-blog/americas-cup-apparent-wind/
and less than 10° for iceboats:
https://www.nalsa.org/Articles/Cetus/Iceboat%20Sailing%20Performance-Cetus.pdf
For more information see:
https://en.wikipedia.org/wiki/High-performance_sailing#Beta_theorem
http://www.onemetre.net/design/CourseTheorem/CourseTheorem.htm
Garrett, Ross (1996). The Symmetry of Sailing: The Physics of Sailing for Yachtsmen. Sheridan House, Inc. p. 268. ISBN 9781574090000.
Kimball, John (2009-12-22). Physics of Sailing. CRC Press. ISBN 978-1-4200-7377-5.
https://books.google.de/books?id=Xe_i23UL4sAC&lpg=PP1&hl=de&pg=PA49#v=onepage&q&f=false
High-speed sailing, Wolfgang Püschl 2018 Eur. J. Phys. 39 044002
https://iopscience.iop.org/article/10.1088/1361-6404/aab982