The Beardmore Inflexible, also known as the Rohrbach VI, was a giant shoulder-wing, three-engined all-metal prototype bomber aircraft built by William Beardmore and Company at Dalmuir, Scotland and developed in the late 1920s.
William Beardmore and Company had acquired a licence for the use of the Rohrbach principle for stressed-skin construction. Using these principles and drawings supplied by Rohrbach for the RoVI, the Beardmore company built a massive all-metal three-engined transport, the Beardmore Inflexible.
The aircraft was built in sections at Dalmuir between 1925 and 1927 which were shipped by sea to Felixstowe and from there delivered by road to the Aeroplane & Armament Experimental Establishment (A&AEE) at Martlesham Heath Airfield where it first flew on 5 March 1928.
It appeared at the Hendon RAF Display later in the year. The aircraft was structurally advanced for its time, proving the feasibility of all-metal aircraft and large monoplanes and had good flying qualities.
It was also a very large aircraft for the time, having a wingspan of 157 ft (48 m) – around 16 ft (4.9 m) greater than the Boeing B-29 Superfortress heavy bomber of World War II. However, with an all up weight of 37,000 lb (17,000 kg) it was underpowered and, with no interest forthcoming from the RAF for a production contract, the aircraft was dismantled at Martlesham Heath in 1930. It was then examined for the effects of corrosion on light-alloy stressed skin structures.
Combined with the financial crash in 1929, this resulted in little further interest and no production models were ordered.
Sources: YouTube; Wikipedia