[3][4] En route from the Persian Gulf to Rotterdam, The Netherlands, via a scheduled stop at Lyme Bay, United Kingdom, the oil tanker Amoco Cadiz, owned by the US-based petroleum company Amoco, encountered stormy weather with gale conditions and high seas while in the English Channel.

This was later found to be due to the shearing of threaded studs in the ram steering gear, causing a loss of hydraulic fluid.

At 10:20, Amoco Cadiz messaged that she was "no longer manoeuvrable" and asked other vessels to stand by, and a call for tugboat assistance was issued later at 11:20.

A successful tow line was in place at 20:55,[5] but this measure proved incapable of preventing the tanker from drifting towards the coast because of its huge mass and storm Force 10 winds.

Her crew was rescued by French Naval Aviation helicopters at midnight, and her captain and one officer remained aboard until 05:00 the next morning.

[6] Amoco Cadiz contained 1,604,500 barrels (219,797 tons) of light crude oil from Ras Tanura, Saudi Arabia, and Kharg Island, Iran.

Sub-surface oil separated into two or three layers due to the extensive sand transfer that occurred on the beaches during rough weather.

French authorities decided not to use dispersants in sensitive areas or the coastal fringe where water depth was less than 50 metres (160 ft).

[citation needed] At the time, the Amoco Cadiz incident resulted in the largest loss of marine life ever recorded from an oil spill.

Two weeks following the accident, millions of dead molluscs, sea urchins, and other bottom dwelling organisms washed ashore.

[9] Footage of the incident appeared in the film Days of Fury (1979), directed by Fred Warshofsky and hosted by Vincent Price.

In 1984, US District Court Judge Frank J. McGarr held that Amoco was liable for damages when he issued his trial verdict, after 3½ years of legal proceedings.