Pemberton-Billing P.B.29E

One of the most extraordinary interceptor fighters flown during World War I, the P.B.29E twin-engined quadruplane was conceived as an anti-airship aircraft. Intended to be capable of prolonged cruise at low speeds during the nocturnal hours, the P.B.29E featured high aspect ratio wings with a pair of 90hp Austro-Daimler six-cylinder water-cooled engines underslung from the second mainplane and driving pusher propellers. The entire wing cellule was braced as a two-bay structure, the fuselage being attached to the second wing and accommodating two crew members, and a gunner with a single 7.7mm machine gun occupying a nacelle that filled the gap between the centre sections of the upper mainplanes. The P.B.29E was flown in the winter of 1915-16, and was destroyed comparatively early in its flight test programme, but aroused sufficient interest to warrant development of the P.B.31E of similar concept. No data relating to the P.B.29E are available.