User talk:Sic Transit
Fleetwood Lower (Beach) lighthouse
[edit]Thanks for creating Beach Lighthouse (Fleetwood). I intended to do it when I uploaded the picture but never got round to it.
Do you have a cite for the lighthouse being 44 ft tall? I had always assumed 34 feet. Oddly enough, I measured it by triangulation when I was at primary school when we were doing the Pythagoras triangle stuff, and I remember distinctly 34 feet. I think the light (maybe 4 or 5 feet from the topmost point) is 44 feet above high tide. --Stevew2022 04:36, 2 February 2008 (UTC)
-- The sources for the heights of the Pharos and Beach Lights are not definitive. The problems are several. Charts give the height of the lights focal plane above MHWS (mean high water spring) while the tradition from Denhams time was to measure lights from the median height of the tide. Neither is an accurate height of the structure. The sources I have found suggest the Pharos is either 89 or 90 feet and the focal plane is 93ft. Beach is 43 with a focal plane of 46ft. The greater focal plane presumably the height from sea level ? I have asked the Fleetwood harbour master for clarification, better yet would, as you point out be an angle measurement. Sic Transit (talk) 18:25, 6 February 2008 (UTC)
-- Let's see what the harbourmaster has to say; it's useless to speculate without any definitive information. Having said that, I am surprised there is such a minimal difference (3 to 4 feet), on both lights, between the structure height and the the height of the light's focal plane above mean high water. Assuming the position of light itself is, say 4 to 6 feet below the height of the structure (a reasonable assumption), that implies that the bases of both structures are only, say, 7 to 10 feet above mean high water. That sounds an underestimate to me, especially for the upper light. Unfortunately, I'm not in a position to repeat the triangulation experiment as I now reside several thousand miles from Fleetwood. Maybe the Surveyor's office at Wyre Borough Council can help?. --Stevew2022 21:58, 6 February 2008 (UTC)