Fog has always been one of the most dangerous conditions a ship can encounter. Unlike a storm, it may leave the sea relatively calm while taking away the one thing sailors depended on most: their ability to see. Before radar, ships relied on lookouts, whistles, bells, and estimates of their position. A vessel could know where it was and still have no idea another ship was only minutes away. Slowing down was the safest response, but schedules, confidence, and misjudgments sometimes kept ships moving faster than conditions allowed.
SS Pacific (1875) — fog/poor visibility surrounding the collision with Orpheus. This shows the nineteenth-century problem when eyesight and sound were essentially all they had.
RMS Republic (1909) – The RMS Republic was a luxury White Star Line ocean liner that sank on January 24, 1909, after colliding with the Italian liner SS Florida in heavy fog off Nantucket, Massachusetts. It made history by using a Marconi wireless CQD distress call, which helped save about 1,500 lives.
Empress of Ireland (1914) — perhaps our best early twentieth-century example. Storstad and Empress saw each other before the fog swallowed them. When visibility disappeared, each captain had to judge what the other vessel was doing.
Andrea Doria / Stockholm (1956) — the perfect radar-era example. They had technology specifically designed to help in poor visibility, yet interpretation and navigation decisions still mattered. And we can briefly mention the proposed Stockholm radar-range error while clearly labeling it as a later reconstruction rather than established fact.
Technology changed. Fog didn’t.
Modern radar, GPS, and electronic tracking have made sailing through fog far safer than it was aboard the Pacific in 1875. But technology has never eliminated the danger. Equipment has to work, information has to be interpreted correctly, and someone on the bridge still has to make the right decision. The tools have changed dramatically over the past 150 years. The fog has not.
Later investigations suggested that Stockholm’s third officer may have believed his radar was set to a 15-mile range when it was actually set to five, making Andrea Doria appear three times farther away than she really was.
Radar greatly reduced the danger of sailing blind, but it could not eliminate human error. Ships could now see one another electronically, but captains still had to correctly interpret that information and act on it.