Sevenstones Lightship

Sevenstones Lightship, LV 7, decommissioned 2008
History
United Kingdom
OperatorTrinity House
General characteristics
TypeLightvessel
Sevenstones Edit this at Wikidata
Map
Coordinates50°03′37″N 6°04′20″W / 50.0603°N 6.0723°W / 50.0603; -6.0723
OperatorTrinity House Edit this on Wikidata
RaconO Edit this on Wikidata
Active light
Focal height12 m (39 ft) Edit this on Wikidata
Range15 nmi (28 km; 17 mi) Edit this on Wikidata
CharacteristicFl(3) W 30s Edit this on Wikidata

Sevenstones Lightship is a lightvessel station off the Seven Stones Reef which is nearly 15 miles (24 km) to the west-north-west (WNW) of Land's End, Cornwall, and 7 miles (11 km) east-north-east (ENE) of the Isles of Scilly. The reef has been a navigational hazard to shipping for centuries with seventy-one named wrecks and an estimated two hundred shipwrecks overall, the most infamous being the oil tanker Torrey Canyon on 18 March 1967.[1][2] The rocks are only exposed at half tide. Since it was not feasible to build a lighthouse, a lightvessel was provided by Trinity House. The first was moored near the reef on 20 August 1841 and exhibited its first light on 1 September 1841. She is permanently anchored in 40 fathoms (73 m) and is 2.5 miles (4.0 km) north-east (NE) of the reef.[3][4] Since 1987, the Sevenstones Lightship has been automated and unmanned.[1]

The Seven Stones lightvessel also acts as an automatic weather station.[5] A series of Trinity House lightships stationed near the Sevenstones Reef have measured significant wave heights (Hs or SWH)—the periodic average of the highest one third of waves in a spectrum—since the early 1960s using Ship Borne Wave Recorders (SBWR).[6] The Sevenstones Lightship is in a very exposed location and is open to most North Atlantic storms.

  1. ^ a b Jones, R. (2011). Lighthouses of the Southwest. Wellington: Halsgrove. ISBN 978-0-85704-107-4.
  2. ^ Gill, C; Booker, F; Soper, T (1967). The Wreck of the Torrey Canyon. Newton Abbot: David and Charles Limited.
  3. ^ Noall, Cyril (1968). Cornish Lights and Shipwrecks. Truro: D Bradford Barton.
  4. ^ Petrow, Richard (1968). The Black Tide. In the Wake of Torrey Canyon. London: Hodder and Stroughton.
  5. ^ Liddiard, John. "Seven Stones". Archived from the original on 12 December 2013. Retrieved 19 February 2012.
  6. ^ "Charting Progress: The State of UK Seas" (PDF). DEFRA. Archived from the original (PDF) on 21 February 2014.