Designed in 1915 by Noel Pemberton-Billing, and built by the company bearing his name, the P.B.23E single-seat pusher fighting scout biplane was of wooden construction, but the nacelle mounted between the wings and accommodating the pilot was unusual for its time in being covered with light alloy sheet metal. Armament consisted of a single 7.7mm machine gun mounted in the nose of the nacelle and power was provided by an 80hp Le Rhone rotary. The P.B.23E was first flown in September 1915, but was not adopted in its original form, being further developed as the P.B.25.