The Felixstowe/ Porte Baby was a three engined flying boat that was developed as an alternative to the Curtiss H-4 ‘Small America’, but that was only produced in small numbers after the success of the Felixstowe F.2A,
The most important figure in the development of the British flying boats during the First World War was John Porte. After he was invalided out of the Navy in 1911, he developed an interest in flying boats. This led to a move to American in April 1914 to help Glenn Curtiss with the design of the Curtiss H-1 ‘America’, which was being built to fly across the Atlantic. However the First World War broke out just as it was about to make the attempt, and Porte returned to Britain. He joined the RNAS, and was given command of the RNAS base at Felixstowe.
In his new position he was able to convince the Admiralty to purchase both of the H-1s and place orders for the improved Curtiss H-4. These aircraft performed well in the air, but were found to be rather too fragile on the water. Porte and his teams carried out a series of experiments with new hulls, producing the single Felixstowe F.1 by fitting the new hull to the wings of the Curtiss H-4. This was followed by the Felixstowe F.2, which again used Porte’s hulls, this time with the wings from the Curtiss H-12 ‘Large America’. The F.2 entered production as the F.2A, and was the start of a family of Felixstowe flying boats.
At the same time Porte began work on a new flying boat of his own design. The new, much larger, flying boat, was almost immediately nicknamed the ‘Baby’, and that name has stuck. The ‘Baby’ was significantly larger than the standard Felixstowe F boats. The single-step plywood covered hull was 56ft 10in long – 10ft longer than the Felixstowe F.2A. Wing span was 124ft, 30ft wider than the F.2A. It was more than twice as heavy, with a empty weight of over 18,000lb. To compensate for the extra weight it was given three 250hp Rolls-Royce engines, two tractors and a central pusher. It had an enclosed cockpit and could carry a crew of five.
The prototype of the ‘Baby’, serial number 9800, made its maiden flight on 20 November 1915. Early tests revealed problems in a following sea, which were solved by extending the bows by 3 ft. It was also underpowered, and could only reach a top speed of 78mph.
The single prototype was followed by ten production aircraft (9801-9810) and ten hulls (9811-9820). Most of the completed aircraft were powered by three Rolls Royce Eagle VIIs of 325hp or Eagle VIIIs of 360hp, although others used a less powerful 260hp Green engine in the central position. The more powerful engines did give the ‘Baby’ a better top speed, but it still wasn’t enough of an improvement to justify putting the larger boat into full production.
The production aircraft were delivered between May 1916 and March 1917, and were used on anti-submarine patrols, mainly from the RNAS bases at Felixstowe and Killingholme. The large boat could be very robust. On 1 October 1917 aircraft 9810 was attached by two German seaplanes and one landplane near the North Hinder Lightship, two of her engines damaged, and forced to land. She survived further German attacks, and her crew were able to fix the engines enough to allow them to taxi slowly across the North Sea, reaching land at Sizewell gap, near Orfordness!
The prototype was used for several experiments. It was fitted with a six-pounder Davis recoilless gun, although there is no evidence that the large gun was actually fired while installed. It was used to carry two torpedoes, one under each wing. The most impressive was its use as a small aerial aircraft carrier, testing out the ‘piggy back’ fighter idea. On 17 May 1916 it took off with a Bristol Scout attached to the upper wing. The Scout successfully detached at 1,000ft, and was able to safely return to land under its own power.
Engine: Three Rolls Royce Eagle VII inline engines
Power: 345hp each
Span: 124ft 0in
Length: 63ft 0in
Empty weight: 14,700lb
Gross weight: 18,600lb
Max speed: 87.5mph at 2,000ft
Climb Rate: 6,500ft in 25 min 5 seconds
Service ceiling: 8,000ft
Armament: Three Lewis guns