The Westland IV commercial monoplane (British)three "Cirrus III" engine
A 1929 NACA aircraft circular, issued through the NASA Technical Reports Server, documenting the British Westland IV three-engined commercial monoplane with Cirrus III engines for an engineering audience. The pictures are mostly sharp black-and-white photographs and technical line drawings of the airframe, including a three-view general arrangement with dimensions and a wing area table, plus close photos of the cowling and a mechanic's footstep. A designer could draw on their clean diagram layouts, grid-based captioning, and the stark, utilitarian tone of early aviation documentation.
