The only feature film made in Dufaycolor, a single-strip color process that had been used previously in two sequences of Radio Parade of 1935 (1934).
The main young actors playing cadets - Simon Lack (24) Nigel Stock(19) and Peter Shaw (21 and later husband of Angela Lansbury) all took part in WW2. Leslie Banks and Cecil Parker had both served and were injured during WW1.
The Dartmouth train station that Leslie Banks enters to catch a train, never saw a train. The line to Dartmouth finally terminated on the opposite side of the Dart river at Kingswear. The building on the Dartmouth side became a ticket office but to catch the train passengers had to take the chain ferry (ferry pulled across by mechanically operated chain pulley). The ferry still operates as does the steam train which is a heritage line.
The external shots of Dartmouth cadets features the cadets of the day as extras. Most of these young men were commissioned onto their ships at the start of and during the early part of the war. Many will not have survived.