HMS Rainbow (N16): Lost Off Calabria in a Mystery That Endures

From Hong Kong to Alexandria

HMS Rainbow served the Royal Navy from 1930, and following Italy's declaration of war in June 1940, was sent from Hong Kong to the Mediterranean, joining the 4th Submarine Flotilla based at Alexandria in Egypt, part of the rapid redeployment of British submarines to meet the new threat in that theatre.

A Final Patrol Off Calabria

Under the command of Lieutenant Commander L.P. Moore, Rainbow sailed from Alexandria on 23 September 1940 for a patrol area off Calabria, a routine assignment that would prove to be her last. She failed to return, and her fate has never been definitively resolved.

A Disputed Loss

Historical accounts of Rainbow's loss remain divided. Some sources hold that she was sunk by the Italian submarine Enrico Toti, a claim now generally believed to have actually involved a different British boat, HMS Triad, while more recent research, developed since 1988, suggests Rainbow herself collided with the Italian merchant vessel Antonietta Costa on 4 October 1940 while attacking a convoy.

Neither candidate wreck has ever been properly surveyed, leaving the true circumstances of her loss honestly unresolved even today.

What is known for certain is the human cost: 57 men were lost in total, one earlier death in February 1937 and 56 more in the presumed sinking on 19 October 1940, a loss that deserves to be remembered with full seriousness regardless of which account of her final hours eventually proves correct.