The Martin-Baker MB.5 design was the best to come from the company during World War 2 - though only a single prototype was ever realized.
Authored By: Staff Writer | Last Edited:
Credit: Image from the Martin-Baker company image archives.
Martin-Baker, who would go one to become a well-known aircraft ejection seat-maker, originally was in the business of aircraft-making, establishing operations in 1929 and becoming the "Martin-Baker" brand in 1934. Its first foray into aircraft design became the civilian market MB.1 which incorporated weigh-savings construction and low-maintenance/operational requirements to produce a lighter, cheaper-to-produce airframe for serial manufacture. The sole prototype was lost to a fire but paved the way for a series of military fighter-minded machines to come.
The MB.2 continued the construction techniques employed in the MB.1 and was evolved along the lines of a possible fighter for service in the Royal Air Force (RAF). The design was not adopted after it showed little improvement over competing types already in service which led to the MB.3, the most modern offering to date for Martin-Baker and, again, developed to a standing Air Ministry fighter requirement. However, just one of the three ordered MB.3 series aircraft flew and this sole example crashed during a test flight - taking the life of company co-founder Valentine Baker with it. From there, the MB.4 was briefly entertained on paper as a Rolls-Royce Griffon-powered fighter retaining many of the physical features of the earlier MB.3. However, this fighter only appeared in drawings and was never seriously furthered.
The culmination of the MB line arrived with the MB.5 - the definitive model in the Martin-Baker wartime family of fighter prototypes - and continued the evolution of the aircraft that began with the MB.1 some time earlier. Its sole prototype actually emerged from the MB.3's development for it was formed from the second - incomplete - prototype that was revised to a newer standard and finished as the impressive MB.5. The aircraft was constructed during early 1944 with the prospect that this product could still fulfill a fighter requirement for the Air Ministry - even though several major participants, namely the Supermarine Spitfire, were holding their own in the advancing war.
The key shift in the MB.5's design approach was the installation of the Rolls-Royce Griffon 83 series liquid-cooled engine of 2,340 horsepower - the most powerful to be fitted to any Martin-Baker aircraft up to this point. Indeed, the Griffon was originally intended for the MB.3 but the powerplant remained in-development and the Merlin was substituted instead (even then, the finalized MB.3 ultimately carried a Napier-branded engine). First flight of the MB.5 prototype was finally had on May 23rd, 1944.
The resulting design was sleeker and more modern in appearance than even the MB.3 before it. The fuselage was well-streamlined from "spinner to tail". The engine, mounted ahead of the single-seat cockpit, drove a pair of three-bladed propeller units in contra-rotating fashion. Up to this point, Martin-Baker fighters employed either two- or three-bladed propeller units in conventional arrangements. The cockpit itself was fitted slightly ahead of midships and utilized a largely unobstructed canopy which provided excellent vision for the pilot. An air scoop was featured under the belly (ala the North American P-51 "Mustang" fighter) and the tail unit incorporated a single vertical tail fin and mid-mounted horizontal planes as seen in previous Martin-Baker aircraft. The undercarriage was wholly retractable as it was in the MB.3, their design somewhat reminiscent of the Supermarine Spitfire (though with a noticeably wider track).
The MB.5's first flight proved it a largely sound aircraft though stability issues soon crept in. This forced a reworking of the rear fuselage section which led to a new tail fin of larger surface area being fitted to help eradicate the encountered longitudinal stability. In 1944 the call came down from the Air Ministry that the MB.5 would not be accepted for adoption nor serial production though it remained in testing even as the war in Europe came to a close during May of 1945.
As impressive as it appeared, the MB.5 also became recognized as an impressive performer with a listed maximum speed of 460 miles per hour and a service ceiling reaching 40,000 feet. Rate-of-climb was 3,800 feet-per-minute and operational range was out to 1,100 miles. The MB.5 was exhibited in the first post-war aircraft flying collection at RAE Farnborough in October 1945 but its flying time was eventually marred by the main section of canopy coming loose on approach and an engine issue stained its impressive display in front of British Prime Minister Winston Churchill himself. Despite this, the aircraft was landed safely with no loss of life.
Evaluation of the aircraft continued as the months ticked on and it grew an excellent reputation as a responsive and high-performance aircraft. The pilots lucky enough to fly her placed her in high regard - its stability perfected and its agility unmatched. Some observers critiqued diving speeds and others its rate-of-climb when compared to contemporaries but few could find any major fault in the overall product. Even throughout the latter part of the 1940s, the MB.5 was still being flown at a time when many in-development wartime projects had been given up to the scrap heap.
An official review cited some failings in the aircraft but these were not shared by test pilots for some considered it the best piston-engined aircraft to ever fly. It is noteworthy that the airframe was never outfitted and flown with the intended cockpit armoring or its battery of 4 x 20mm Hispano Mk II cannons in the wings so it's true performance figures would (and could) never be realized (performance under combat loads was a very different beast to judge an aircraft by).
Its flying days ended sometime in the late 1940s (its last flight may have occurred in 1947) to which the airframe remained under RAF ownership and may have (rather unfortunately) been expended as a target or in some other unflattering training exercise. Such came the end of the impressive MB.5.
Even so, the design endeavors of the MB series were quite a journey for the Martin-Baker company. It ended its aircraft-making days when it shifted priorities to pilot safety and became an industry stalwart in providing ejection seats for many jet aircraft of the Cold War period (1947-1991). The company continues in this respect.
[ 1 Units ] : Martin-Baker - UK
United Kingdom (cancelled)
- X-Plane / Developmental
37.73 ft (11.5 m)
35.10 ft (10.7 m)
14.76 ft (4.5 m)
(Showcased structural dimension values pertain to the Martin-Baker MB.5 production model)
9,237 lb (4,190 kg)
12,092 lb (5,485 kg)
(Showcased weight values pertain to the Martin-Baker MB.5 production model)
1 x Rolls-Royce Griffin 83 V-12 liquid-cooled inline piston engine developing 2,340 horsepower driving 2 x three-bladed propeller units in contra-rotating fashion.
(Showcased powerplant information pertains to the Martin-Baker MB.5 production model)
460 mph (740 kph; 400 kts)
39,993 feet (12,190 m; 7.57 miles)
1,100 miles (1,770 km; 956 nm)
3,800 ft/min (1,158 m/min)
(Showcased performance values pertain to the Martin-Baker MB.5 production model; Compare this aircraft entry against any other in our database)
PROPOSED (never fitted):
4 x 20mm Hispano Mk II cannons in wings.
(Showcased armament details pertain to the Martin-Baker MB.5 production model)
MB.5 - Base Series Designation; sole prototype completed and ultimately scrapped.
The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com.
Part of a network of sites that includes AnvilOfWar.com, GlobalFirepower, a data-driven property used in ranking the top military powers of the world, and WDMMA.org, the World Directory of Modern Military Aircraft.