The Cape Hatteras Lighthouse is not flashing.
The spindle motor that causes the light to beam seaward every 7.5 seconds has stopped working. The Coast Guard is working on the problem and is not certain when it will be fixed, said Petty Officer 2nd Class Nate Littlejohn, a spokesman.
The Aids to Navigation Team is looking for a replacement motor and parts, Littlejohn said. The Coast Guard has been issuing an hourly marine broadcast to notify mariners of the problem, he said.
Since 1950 the light has used a DCB 224 aerobeacon, a device where two 1,000 watt bulbs protected by aluminum drums burn in front of parabolic reflectors, according to a University of North Carolina website. The motor and drive gears just below make the lights rotate. The Coast Guard regularly maintains the light, wiring and gears, Littlejohn said.
An automatic switch turns the light on and off 30 minutes before sunset and 30 minutes after sunrise, allowing for the lengthening or shortening of the day.
Mariners depend on GPS but still look for the 210-foot black-and-white-striped tower with the flashing light that can be seen at least 20 miles offshore.
For centuries, ships attempted to navigate the dangerous shoals as they passed the North Carolina coast. Often, vessels struck bottom and sank.
The area is still known as the Graveyard of the Atlantic.
The beacon was first constructed in 1802 at the Hatteras point. But the first structure was short and the light too dim. The latest structure was erected in 1870.
In 1999, the entire lighthouse was lifted and moved inland 2,900 feet to escape the encroaching ocean.