 | ||
Example of a sector light
An example of a sector light is the light of the Fisgard Lighthouse in British Columbia. The lighthouse as built to guide ships through the entrance of Esquimalt harbour. The white sector is an isophase light of 2s from 322° to 195°. If the ship sees this white light, it can pass safely. The rest shows a red light from 195 to 322°. If a vessel sees this light, it should alter its course.
Another example is the PEL sector light at Diego Garcia. The PEL sector light was constructed to guide US Navy vessels into the Diego Garcia port through a narrow entrance in the lagoon. The PEL sector light produces 3.5 million candela and is visible for 10 nautical miles (18.5 km) by day. The beam with 3 colors is narrow at 1.6°. This was required because the PEL sector light was built over 7NM (13 km) from the atoll entrance and it had to illuminate a safe entrance which is only 228 meters wide.