One of the most obscure piston powered aircraft projects ever conceived by a British corporation has to be the Martin-Baker MB series. The small English company, founded by James Martin and Val Baker in the early 1930s, was at the outside looking in terms of the British Royal Air Force’s design and development programs. But that changed in the summer of 1938 (August 3rd) when the company’s MB-2 single seated fighter, powered by a Napier Dagger engine, took to the air on its maiden flight. The aircraft flew flawlessly prompting the RAF to take a hard look at the, by that time, unknown corporation. Martin-Baker followed the success of the MB-2 with the MB-3. The new air platform was design around a May 1939 Ministry of Defense (MoD) specification, F-18.39, which called for an aircraft that can ascertain speeds above 400 mph within a heavily armed airframe. The new 3 version would have been able to achieve the stated speed at an operational ceiling of 15,000 feet. It was designed with a powerful six 20mm cannons fitted along its wing structures. Only one MB-3 sample, unit R2492, flew. It did so on August 3rd 1942. Unfortunately the unit was lost a month later when during a routine testing exercise; the aircraft staled in mid air prompting the sample to plumb to the ground. The crash, not only put the entire MB-3 program in jeopardy, but the death of the test pilot, company founder Baker; was a serve blow that would have dire consequence for the small company in the years ahead.
Constant development and production delays assured that the MB-3 would never achieve full production status. In the sprig of 1943, the MoD canceled its pre-production order for the 3 version. With the end of the company’s biggest contract up to that date, James Martin was finally free of government constraints. Free to pursue his life log dream. Free to design the company’s greatest air structure, the MB-5. The version 5 of the basic MB concept was basically a redesigned MB-4, an air platform that was never developed past mockup status, with a more powerful engine base and a streamline fuselage. The new power plant planned for the 5 version was the Rolls-Royce Griffon engine. The engine, coupled with a new teardrop canopy design and rear fuselage radiator gave the 5 a distinct flying capability.
The MB-5 in flight. (photo, via author)
Although different in many aspects from the 3 unit, the 5 was also loosely based on the same 18.39 specification. Martin’s new airplane made its maiden flight on the morning of May 23rd 1944. It only took one flight for Martin and the rest of his dedicated staff to know they had something special in the aircraft. With a top speed profile of 460 mph, the MB-5 was able to outrun the best of the Luftwaffe’s piston engine fighters. It flight operational ceiling was 20,000 feet which again, was better than any German piston aircraft of the times. The 5 unit was an overwhelming success that an Aircraft and Armament Experimental Establishment’s Boscombe Down report called the basic MB-5 design “an excellent and infinitely better, from the engineering and maintenance point of view, than any other similar type of aircraft”. The plane was also a big success with all the pilots who flew it. Its streamline airframe made it easy to maneuver it and its reinforced wing structure gave it the stability to become one of the world’s best gun platforms. Despite the high acclimates the aircraft ran into the same problem as the 3 version, delays. Add to this the fact that World War II has just ended, and the “writing was on the wall” when it came to the future of the whole 5 program. In the fall of 1945, the company finally pulled the plug on its most successful aircraft design.
Martin will go on with the design and development two jet powered aircraft, but by the late 1940s the company shifted its overall philosophy towards the production of ejection seats and area that made this little British company a household name.
– Raul Colon
The Royal Air Force and Aircraft Design 1923 to 1939, Colin Sinnott, Frank Cass 2001
Bristol Aircraft since 1910, C.H. Barnes, Putman Books 1964
Planemakers II, David Mondey, Jane’s Defense, 1982