timeline item
Here is the information we have
on the item you selected
More like this
| |
sign up for our newsletter
© 2017 Engineering Timelines
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
Seven Stones Lightvessel
between Land's End in Cornwall and the Scilly Isles
associated engineer
Not known
date  not known exactly, estimate 1960s
era  Modern  |  category  Lighthouse  |  reference  SW087257
The Seven Stones lightvessel is anchored 24km west north west of the Longships lighthouse off Landís End, in the most exposed position of any British lightvessel. These vessels, which act as lighthouses at sea, are maintained in England and Wales by Trinity House, just like their land-based relatives.
Lightvessels have to be towed to and from their stations as they have no means of propulsion. To make them conspicuous in daylight, all have red-painted hulls. The Seven Stones lightvessel has a metal hull and is some 41m long with a beam of 6m — about the same size as a large trawler. She has a single mast in the bow and the lantern is mounted on a tower amidships. A helicopter landing pad was built onto her stern in 1978.
The vessel was manned originally by a crew of ten keepers, with five on station at a time. However, she has been unmanned since 1987, when most of the accommodation and storage was stripped out and replaced with foam to ensure that she stays afloat even if a collision should occur. She has broken free of her moorings on several occasions, and is now secured by some 550m of heavy chain — each link 44mm thick — to a 4 tonne anchor. She carries two spare cables and anchors.
The present lamp flashes white three times every 30 seconds, and is visible for 40km. The fog signal sounds three blasts every 60 seconds.
Although there has been a lightvessel in this location for a long time, probably since the Victorian era, the actual ship has been replaced several times. In October 2007, Trinity House announced that the present vessel will be withdrawn and a replacement established. The new lamp will be positioned at least 12m above the water line and will have a nominal range of 24km.
Records show that a meteor exploded over a previous incarnation of the Seven Stones lightvessel, at 2am on 13th November 1872, showering the deck with cinders.
Research: ECPK
"Cornwall's Lighthouse Heritage" by Michael Tarrant
Twelveheads Press, Truro, 1993

Seven Stones Lightvessel