Royal Aircraft Factory S.E.4a

Royal Aircraft Factory · United Kingdom · first flew 1915 · fighter

The Royal Aircraft Factory S.E.4a was an experimental British single-engined scout aircraft of the First World War. Four were built.

Recognition (WEFT)

W — Wings	Mid-mounted, straight
E — Engines	1 × piston, nose-mounted
F — Fuselage	6.35 m fuselage
T — Tail	Conventional

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Spot it by:

Single-engined, single-bay biplane with noticeable stagger between upper and lower wings
Rotary engine driving a two-bladed propeller
Lewis gun mounted above the upper wing

The fuselage had a steel tube forward section and a wooden box-girder rear section. The wings had full-span control surfaces that could move as ailerons or together as camber-changing flaps.

Specifications

The Royal Aircraft Factory S.E.4a has a length of 6.35 m (21 ft).
It has a wingspan of 8.36 m (27 ft).
Its maximum speed is 145 km/h (90 mph).
Typical crew: 1.

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Henry Folland designed it in 1915 to investigate the relationship between stability and manoeuvrability. Despite its type number it had little or no relationship to the earlier S.E.4, and the first prototype flew on 25 June 1915.

Variants

The first prototype had a smoothly faired fuselage and an 80 hp Gnome rotary engine in a cowling, which overheated and was replaced. The other three had simpler flat-sided fuselages and engines including the Clerget and Le Rhône rotaries.

Where you'll see it

It proved easy to fly and showed excellent aerobatic ability but was overweight and underpowered, and was not developed further. Two were issued to Royal Flying Corps Home Defence squadrons in the winter of 1915 to 1916, and the third prototype was used for trials until September 1917.

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