AMOREST

Herewith BBC link to Launch Video of MV Hebridean Isles - Retired to be scrapped Today. Knock out the struts and run like **** 🤣...

There you go. Non-Return Valve. 25mm (1"), 38mm (1.1/2")

Somewhat like this. Whale LV1219 No-Return-Valve for 19mm ID Hose - buy online

App called Celestial Navigation - Sextant Sight Reduction does what you’re looking for. I used this on Transat last year. Set up...