John Seabourne Sr. directed the "Lobster Pot" scenes in the North Sea despite being seasick the whole time.
Actor Emrys Jones (Bob Ashley, wireless operator and footballer) was an international soccer player before the war. The character was made to be a footballer because he could already play well.
Feature film debut of Peter Ustinov.
One day Noel Coward visited the set and after seeing how the crew staged and wrapped up an elaborate sequence in about 2 hours decided to use most of them on his film In Which We Serve.
The character Sir George Corbett (played by Godfrey Tearle) was reported to be fashioned after the real life Sir Arnold Talbot Wilson. In 1939 he joined the RAF at age 55. He died in 1940 when his airplane crashed in France.
The extra squadron members were all active members of the RAF (XVI) squadron.
The film has no musical score at all (a rarity). The opening titles play over the sound of the bomber's engines.
The model of Stuttgart used in the bombing raid was made by David Rawnsley at the Riverside Studio, Hammersmith and filmed by Frederick Ford.
This film's closing epilogue states: "That was going to be the end of our story. BUT - first, the Actors . . . - and then the Technicians - . . . all of them wanted to know what happened afterwards to the crew of the B for Bertie. So - three months later - . . . THE NETHERLANDS WILL RISE AGAIN!"
This film's opening prologue inter-title states: "B. for Bertie crashed on Sunday Morning, 0431, but our story starts some sixteen hours earlier . . . . . . "