Flower Class Corvette - Armament

Armament

The original Flower class were fitted with a 4 inch (102 mm) gun on the bow, depth charge racks carrying 40 charges on the stern, a minesweeping winch, and a 2-pounder (40 mm) pom-pom gun on a "bandstand" over the engine room.

Due to initial shortages, a pair of Lewis guns was sometimes substituted for the pom-pom, which would have left the ship very vulnerable to aircraft attack in its envisaged role of coastal convoy escort and patrol in the North Sea. The long-range endurance of the vessels, coupled with early war-time shortages of larger escort warships, saw Flowers assigned to trans-Atlantic convoy escort where Luftwaffe fighter-bombers were rarely encountered. Vessels assigned to the Mediterranean Sea usually had their anti-aircraft capability significantly upgraded.

Detection capability was provided by a fixed ASDIC dome; this was later modified to be retractable. Subsequent inventions such as the High Frequency Radio Detection Finder (Huff-Duff) were later added, along with various radar systems (such as the Type 271), which proved particularly effective in low-visibility conditions in the North Atlantic.

The Flower class had been designed for inshore patrol and harbour anti-submarine defence; therefore, many required minor modifications when the Allied navies began deploying these vessels as trans-Atlantic convoy escorts. These small warships could be supported by any small dockyard or naval station, so many ships came to have a variety of different weapons systems and design modifications depending upon when and where they were refitted; there is really no such thing as a 'standard Flower-class corvette'

Several of the major changes that vessels in the class underwent are indicated below, in a typical chronological order:

• Original twin mast configuration changed to single mast in front of the bridge, then moved behind the bridge for improved visibility.
• Heavy minesweeping gear removed for deep-sea escort work and to improve range.
• Galley relocated from the stern to midships.
• Extra depth-charge storage racks were fitted at the stern. Later, more depth charges stowed along walkways.
• Hedgehog fitted to enable remote attacks while keeping ASDIC contact.
• Surface radar fitted in a "lantern" housing on the bridge.
• Forecastle lengthened to midships to provide more accommodation and better seaworthiness. Several vessels were given a "three-quarters length" extension.
• Increased flare at the bow. This and the above modification created the modified Flower design for subsequent orders.
• Various changes to the bridge, typically lowering and lengthening it. Enclosed compass house removed.
• Extra twin Lewis guns mounted on the bridge or engine room roof.
• Oerlikon 20 mm cannons fitted, usually two on the bridge wings but sometimes as many as six spread out along the engine-room roof, depending on the theatre of operations.

Note that any particular ship may have had any mix of these (including none), in any order, or other specialist one-off modifications. Ships allocated to other navies such as the RCN or USN usually had different armament (3 inch {76 mm}/50 cal) and deck layouts.

A major difference between the RN vessels and the RCN, USN, and other navies' vessels was the provision of upgraded ASDIC and radar. The RN was a world leader in developing these technologies, and thus RN Flowers were somewhat better equipped for remote detection of enemy submarines. A good example of this is the difficulty that RCN Flowers had in intercepting U-boats with their Canadian-designed SW1C metric radar while the RN vessels were equipped with the technologically advanced Type 271 centimetric sets. In addition, RCN vessels were incapable of operating gyrocompasses, making ASDIC attacks more difficult.