Martin-Baker MB.1

The M.B.1 was built primarily to demonstrate Martin's original patented system of lattice-girder construction patented by James Martin in 1931. Designed during the late summer of 1934 and was a two-seat low-wing cabin monoplane.

The entire primary structure was built from thin gauge high-tensile steel tube, cut to a precise length with a hacksaw. The tube ends were secured to each other either by brazing or (more frequently) by flattening, brazing and drilling the ends, then fastening with a bolt to a castle-nut brazed inside a small cylindrical insert fixed in the adjacent tube. The advantages of this type of metal structure were simplicity and lightness of construction, versatility, and the benefit that unskilled labour could be utilised during manufacture. Martin was especially concerned that his new aircraft, known simply as the MB.1, should be straightforward to construct and maintain. Because very little light alloy was used in the manufacture, delay and cost through heat treatment and anti-corrosion processes was avoided to a great extent. All the elements for the tubular structure, inserts, saddle--washers and castle-nuts, were produced in-house.

The low set monoplane wing of the MB.1 wing spar was based on three span-wise thin-gauge steel tube booms, two forming the aft surface, one mounted almost vertically above the other, and the third forming the leading-edge. These booms became thinner, and tapered towards each other towards the wingtip. The wide base of this pyramidal spar, together with the large diameter of its component booms, provided considerable strength, especially in torsion. Inserts and bolts secured linking tubes which were used to add to the spar strength. Wing-ribs constructed from brazed small-diameter T.5 tube were then bolted to the spar, as were the wing stringers. Welded aluminium fuel tanks of long, thin triangular section were mounted inside the spars. The wings of the MB.1 were designed to fold, to minimise storage space, the folding procedure being a one-man operation. The same method of manufacture was also used on the tail surfaces.

The rear section of the fuselage was also of bolted tube. Machined, flanged steel sleeves, attached to the longerons at focal points, provided stringers, the area being faired by light metal hoops of near-oval shape. The mid and forward fuselage construction was principally of brazed tube. Evidence of Martin's attention to systems detail was provided by the cock assemblies, for fuel supply, pump isolation and other functions which were loaded with a spring-ball giving 'feel' when they were actuated.

The MB.1 was powered by a 160hp (119kW) Napier Javelin IIIA six -cylinder inverted in-line engine, with electric starting, lent to Martin-Baker by Napier. A fixed-pitch two-bladed wooden airscrew was fitted, the engine installed in a brazed tubular mounting. The practical nature of the MB.1 was particularly evident around the nose where the doping pump had connections to both the carburettor and the induction pipe, the inlet manifold being lagged and warmed, the fuel and oil filters being easily accessible.

The cowling side panels could be supported from their hinges in a horizontal position to form shields should maintenance be necessary while the engine was running.

The MB.1 was entirely fabric-covered apart from the fin and the wing walkways which wore Duralurnin skins. Undercarriage arrangements were very simple and again employed tubular construction with uncomplicated shock absorber struts and low-pressure tyres.

By the end of March 1935 the aircraft was completed and it was taken by road to Northolt. It was eventually given the civil registration G-ADCS, and Capt Baker took the aircraft for its first flight in April 1935, painted black overall. He found that it possessed good flying qualities and had a maximum speed of 125 mph. The company recorded that 'DCS had "sound inherent flying qualities".

With severe cash flow problems, only one MB.1 was built, flying for only a few hours before being placed in storage at Denham after work began on the M.B.2, but in August 1939 the M.B.1 was inspected (and rejected) byAir Ministry representatives for possible impressment into national service.

It is 99 per cent certain that it was burnt in an April 1940 fire at Denham, which destroyed the existing factory. It was definitely not lost in a fire in March 1938.

Engine: One 160hp (119kW) Napier Javelin IIIA six-cylinder in-line piston
Max cruising speed 140mph (225kph)
Stalling speed 50 mph (80kph)
Endurance 3 hrs 30 mins
Empty weight 1,5601b (707kg)
All-up weight 2,3501b (1,065kg)
Wing span 37ft (11.2m)
Length 28ft 10in (8.7m)
Height 9ft 9in (2.9m)
Wing area 206sq.ft (19.1sq.m)