01/31/2008. Remarks by Johan Visschedijk: "In 1916 the Pemberton-Billing Ltd. designed and started construction of the P.B.31E airship fighter. The company was renamed The Supermarine Aviation Works Ltd. in December 1916, and the Supermarine P.B.31E (better known as the Night Hawk) was first flown by Clifford Prodger in February 1917.

Grossly underpowered with two unreliable 100 hp Anzani nine-cylinder air-cooled radial engines, the aircraft reached 10,000 ft (3,048 m) in 60 minutes and a maximum speed of 75 mph (121 kmh). Although two aircraft were ordered, s/n 1388 and 1389, only the first was flown briefly before the shortcomings of the aircraft were appreciated and on July 23, 1917, the project was cancelled and subsequently the first prototype and the partially complete second prototype were scrapped.

The five-seat quadruplane featured a heated and enclosed cockpit, and a nose-mounted searchlight that received its power from a generator driven by a 5 hp A.B.C. flat-twin engine. Armament consisted of a 1.5-pounder Davis gun with 20 shells, and two .303 in (7.7 mm) Lewis guns."