navy) were adapted to replace it. No. 5 (Operational) Dress Operational dress uniforms are designed for wear in combat conditions. They are intended to be adjusted for comfort and practicality; therefore only naval combat dress has lettered variants. With the elimination of work/garrison dress, operational dress uniforms are now commonly worn whenever service dress is impractical. Naval Combat Dress (NCD): Worn by all RCN shipboard personnel. Consists of black trousers and jacket with a blue shirt, made of Nomex for fire protection and designed for wear by ships' crews. No. 5: full NCD, including jacket No. 5A: No. 5 without jacket No. 5B: No. 5A with sleeves rolled No. 5D (tropical shipboard): No. 5B with shorts and knee socks in place of regular trousers. Worn only aboard ship in hot climates. Field combat clothing: Worn by all army and air force personnel, as well as navy personnel assigned to army or air force units. The CAF combat uniform consists of loose-fitting Canadian Disruptive Pattern (CADPAT) shirt and trousers and is designed to be worn in the field or for working around aircraft. This uniform is usually referred to simply as CADPAT. Flying clothing: Green flying suits are worn by CAF aircrew. Distinctive Environmental Uniforms Although the Canadian Armed Forces are a single service, the respective environmental commands are issued Distinctive Environmental Uniforms (DEU) unique to each command. Commands with their own DEUs include the Canadian Army, Royal Canadian Air Force, Royal Canadian Navy, and Special Operations Forces Branch. While DEU refers to all the different environmental uniforms used by the forces, in colloquial usage it refers to what is formally known as "No. 3 (Service) Dress". History Shortly after the armed services of Canada were unified into the Canadian Armed Forces, the service-specific uniforms (navy blue, khaki, and light blue) were abandoned in favour of the Canadian Forces rifle green, single-breasted, four-button tunic and pants, with beret or service cap uniform, commonly referred to as "CFs" or "CF greens". Though accommodation was made for army regiments' ceremonial dress uniforms, no allowance was made for the Navy or Air Force, with the exception of a rifle-green wedge cap for optional wear by the latter. The traditional Navy and Air Force rank names were replaced by the army equivalents, with naval-style rank badges for officers and army-style for non-commissioned members. Navy rank names were restored a few years later. However, the Air