Another view of the P.B.31E, later called Nighthawk, at the Woolston works. The star louvres behind the nose-mounted searchlight were to provide cooling air to the auxiliary ABC engine that powered the light. The aircraft is fitted with a Lewis gun on the nose mounting and a recoilless Davis gun in the upper gun position.

The completed P.B.29E at RNAS Chingford in early 1916. The Austro-Daimler engines were mounted in pusher configuration and drove four-bladed propellers. Ailerons were fitted to all four wings.

A previously unpublished photograph of the P.B.29E under construction at Woolston in 1915. The aircraft was designed and built in little more than two months, such was the need to counter the Zeppelin menace, which was threatening to undermine public morale. The aircraft was transported to Chingford and flown in January 1916.

A poor-quality but very rare photograph of the P.B.29E following its completion. Note the searchlight mounted in the nose and the gun-equipped nacelle between the centre-sections of the upper wings.

The P.B.31E Nighthawk after its completion; it was deemed an improvement over the P.B.29E “Battle Plane", but still struggled to impress.

The completed Nighthawk, minus guns and searchlight, awaits its delivery to Eastchurch in December 1916. One of the most distinctive features of the P.B.31E was its extensively glazed cabin, in which the pilot sat forward of the leading edge of the third wing. Glazed panels in the fuselage served to improve the view downwards.

Огромный для своего времени, Supermarine Night Hawk мог находиться в воздухе до 18 часов. P.B.31 имел размах крыла 18,29 м, максимальную взлетную массу 2788 кг и массу топлива 1016 кг.
The P.B.31E proved to be underpowered, and was scrapped in March 1917. Pemberton Billing (whose name had no hyphen, despite his attempts to adopt one) continued to work on his unorthodox, but often innovative, concepts for aviation, including an unbuilt pre-Second World War concept for a flying-bomb. He died in 1948.

Two P.B.31Es were ordered by the RNAS in November 1916, and were allocated serials 1388 and 1389. The first is seen here at Woolston with Pemberton Billing staff. Fourth from left in the group standing by the machine, in the back row, is R.J. Mitchell, who joined the company in 1915. The second machine was never completed.

A fragment of Pemberton Billing company drawings of the P.B.31E, signed by a young draughtsman by the name of R.J. Mitchell and dated September 18, 1916. It is unknown whether the future designer of the Spitfire had any input into the P.B.31E, but it is more likely he was only providing drawings at this time.