Martin Baker - Ejection seat and escape system technology

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The first design of the MB1 was a low-wing monoplane design, and this in itself was heresy, for the first British monoplane, civil or military, had yet to fly operationally. Also unconventional was the installation of the Gipsy engine, mounted in the fuselage behind the seats, driving a fixed-pitch propeller through a shaft running horizontally between the pilot and passenger, who sat side by side. This arrangement and the general configuration of the aeroplane gave the pilot excellent all-round visibility, making it, with its low stalling speed, a very safe machine. At the same time its low structure weight and simple construction would have made it economical to operate and easy to maintain. Unfortunately, slender financial resources prematurely terminated work on this project, at a stage when all but the wings were completed; engine runs and other ground tests had been carried out in the astonishingly short time of three months.

It was at this stage, too, that the Company took on the construction of an interesting autogyro design by Mr. Raoul Haffner, which was later tested by Captain Valentine Baker at Heston. With some financial aid from a business friend with an interest in aviation, Martin now turned to the design and manufacture of a small, cheap two-seater aeroplane to exploit a simple but highly ingenious method of construction, using round-section thin-gauge steel tubing throughout the structure. The fuselage strut ends were flattened brazed, and drilled holes picked up on bolts supported in the steel longeron tubes. Machined, flanged steel sleeves, fitted on the longerons at focal joints, provided, by holes drilled around their periphery, a means of attachment of fuselage struts, the whole being faired by light metal hoops of near-oval shape. Based, like the fuselage, upon simple construction, the wing was built around a pyramidal spar consisting of three large-diameter but thin-gauge booms, braced by smaller tubes and converging towards one another at the wing tip. The wing struts and ribs, and also the tail unit components, were fastened to the spars in a similar way to the fuselage construction.

For economy of storage space the wings were designed to fold rearwards. Wing folding was a one-man operation, the front pin being on a screw operated by a handle, whilst the rear hinge was designed to prevent the wing falling backwards into the fuselage when the front pin was released; the wing in the closed position came finally against a stop. Long triangular welded-aluminium fuel tanks, designed to be quickly detachable, were carried in the centre of each wing spar. This machine became the MB1 and was powered by a neatly cowled Napier Javelin engine, a 6-cylinder in-line unit producing 160 h.p., flexibly installed in a tubular mounting with all parts accessible for easy servicing, electrically started and driving a fixed-pitch wooden propeller. A sturdy, yet light, tubular-construction undercarriage carried low-pressure tyred wheels and employed shock-absorber struts of simple design.Although the main interest of this aeroplane was in its simple design, much forethought was given to its cockpit layout and general facilities. A contemporary aeronautical journal reported, "The seats are comfortable and the cockpit is totally enclosed with an oval transparent hood. The windscreen is a sharp vee, with vertical front panes, which should not collect fine rain or snow and should obviate any reflection from internal or external lighting."
Aerodynamically a straightforward design, when flight tested in April, 1935, the MB1 was found to possess sound inherent flying qualities which later became a characteristic of the Martin breed of aeroplanes. Top speed was 125 m.p.h. Although the MB1 did not go beyond the prototype stage, many valuable lessons were learnt during its design, construction and testing, which were to be used in the production of the Company's next design.

Martin-Baker MB1