Farman HF.30

The Henry Farman HF.30 was a two-seat biplane designed as a fighter in France in 1916 and powered by a single, water-cooled radial engine. It showed poor flight characteristics and only one was built, though it was modified twice. It should not be confused with the similarly named Farman F.30 of 1915, a completely different aircraft which was used in large numbers by the Imperial Russian Air Service.

Design and development
The Henry Farman HF.30 was amongst the last Farman aircraft to be produced under Henry Farman's name, before the brothers formally joined forces. It represented a departure from the pusher configuration with which they had previously been associated, in which the propellor was mounted amidships at the rear of the engine, and the tail was only a lightweight framework for the control surfaces. The HF.30 adopted what was becoming the more conventional aeroplane design, with the propeller at the front and a continuous streamlined fuselage. It first flew in December 1916.

The HF.30A was a metal framed biplane with considerable overhang of the upper planes, a fairly common feature of Henry Farman's designs (as in the F.40), though possibly it was not strictly a sesquiplane. The inner part of the wing structure, out to the tips of the lower wing, formed a single bay unit, without stagger and braced by simple parallel interplane struts. These struts continued above the upper surface, with the outer parts of the upper wing wire braced to them. Ailerons were fitted to the outer, upper wings.

The fuselage was mounted between the wings on central struts above and below and was circular in cross-section, tapering towards the tail. The horizontal tail surfaces were rectangular, and the rudder and wide chord fin formed a shallow triangle. There were two cockpits, seating the pilot under the wing and the gunner further aft with a large radiator between them. The 260 hp (120 kW) water-cooled Canton-Unné X-9 radial engine gave the HF.30A a short nose. Its simple conventional undercarriage had a single mainwheel on each main leg and radius arm.

By May 1917 the HF.30A was undergoing official evaluation by la Section Technique de l'Aéronautique (STAé ) at Villacoublay. They disliked the positioning of the radiator between the two crew and found the handling poor, rejecting the aircraft. Farman then modified it by shortening the upper span and using a more powerful engine, another water-cooled radial, the 260 hp (195 kW) Salmson 9Za. They returned to the STAé with it, now designated HF.30B. After more test flights the STAé called for further changes, requiring the wing area to be increased from 34.7 m2 (374 sq ft) to 54 m2 (581 sq ft). Farman did this with an increase of span, the larger upper wing now extending 14.0 m (45 ft 11 in) from tip to tip. Trials of what was now known as the HF.30B-AR 2 at the STAé resumed at the start of 1918 but by April the lack of both lateral and longitudinal stability caused tests and the aircraft's development to be abandoned.

Variants

 * HF.30A
 * 160 hp (120 kW) Canton-Unné X-9 water-cooled radial engine. Flew December 1916.


 * HF.30B
 * Modification with 260 hp (195 kW) Salmson 9Za 9-cylinder water-cooled radial. Span shorter by 1.79 m (5 ft 10 in), fuselage longer by 1.0 m (3 ft 3 in). Flew July 1917.


 * HF.30B-AR 2
 * Modification of HF.30B, with upper wing span extended to 14.0 m (45 ft 11 in). Flew 1918.