| NISSENHUT | Prefabricated steel structure, widely used during World War II (6,3) |
| NISSEN | Surname of the inventor of a prefabricated steel structure, made from a half-cylindrical skin of corrugated steel, designed during the First World War |
| COLT | What make of pistol was most widely used during the American Civil War? (4) |
| TELESCOPE | Steel structure, manage to slide inwards |
| NODEHOUSE | Prefabricated shelter used by welders during the construction of an oil rig (4,5) |
| OFLAG | Type of German prisoner-of-war camp for captured enemy officers, chiefly used during World War II (5) |
| ENIGMA | German encryption machine used during World War II (6) |
| READYMADE | Prefabricated (5-4) |
| KILROY | James J ?, US shipyard inspector believed to have originated a popular expression used during World War II (6) |
| MERLIN | Small species of falcon; also the type of Rolls-Royce engine used during World War II in the Hurricane and Spitfire (6) |
| MAEWEST | Actress who gave her name to yellow life preserver jackets used during World War II (3,4) |
| SPITFIRE | Fighter plane used during World War Two (8) |
| ANDERSON | _ shelter, a small prefabricated air-raid shelter used during the Second World War (8) |
| HORIZONTAL | ____ bar, a steel structure used for swinging and vaulting exercises in gymnastics (10) |
| PYLON | Steel structure only demolished under pressure |
| KEEL | The lengthwise timber or steel structure along the base of a ship (4) |
| RESOLUTE | Our steel structure is unbending (8) |
| LIBERTYSHIP | Prefabricated vessel, one of many massproduced in the US during the Second World War (7,4) |
| BAILEYBRIDGE | Prefabricated structure that is quickly erected in emergencies (6,6) |
| TERRAPIN | Temporary portable prefabricated structure, especially a school classroom (8) |
