The Sikorsky S-61 disaster occurred when a helicopter operated by the British International Helicopters crashed into the sea off the Isles of Scilly. The helicopter was traveling from the Royal Naval Air Station at Culdrose to the St. Mary's airport when it suddenly lost altitude and plunged into the water, resulting in the loss of all 20 lives aboard. Witnesses reported hearing a distress signal just moments before the crash, but the exact cause of the failure remained uncertain. The search and rescue operation was launched quickly, but unfortunately, no survivors were found. The event not only left a deep impact on the families of the victims but also raised significant concerns regarding aviation safety protocols at the time.

In the aftermath, investigations were conducted to determine the contributing factors leading to the crash. Various factors, including mechanical failure and environmental conditions, were scrutinized. The incident led to renewed discussions about the importance of maintenance and operational safety within the aviation industry, particularly concerning commercial helicopter services. Following the tragedy, new regulations and guidelines were implemented to enhance safety measures for passenger aircraft, especially helicopters operating in challenging maritime environments.