Type 150 Vanox

Bomber prototype designed to meet Specification B.19/27.
Vickers Type 150 Vanox 12 deg sweep 1930 RAF Pageant The Vickers Type 150 B.19/27 J9131 prior to the 1930 RAF Display at Hendon.
The Vickers Aviation Type 150 was designed as a replacement for the Vickers Virginia to meet Specification B.19/27. In the event, it did not receive a production contract and was subject to progressive modifications as the Type 195 and Type 255, before ending its days conducting air-to-air refueling trials.
The specification had called for an aircraft of all-metal construction that would provide a steady bomb platform. A twin-engine design was assumed, with defensive armament and design for ease of maintenance. A speed of 120 mph was required at 10,000 ft with a bomb load up to 2,500 lb, alternative loads including 2 x 1,000 lb, or 4 x 550 lb, or 10 x 250 lb, or 16 112 lb bombs and 4 x 20 lb bombs for sighting or practice purposes. A range of 920 miles at 115 mph was also required as well as three Lewis guns required for self defence.
The design was a large, unequal span twin-engine biplane, with a single-bay outside of the engines on each side. The engines would be mounted midway between the two wings whilst moving tail surfaces comprised a pair of narrow chord rudders and an all-moving tailplane.
The design was initially configured around the use of the Bristol Mercury engine, but a change was agreed in August 1928, to the use of two Rolls-Royce F.XIV liquid-cooled engines. The sole prototype featured twelve degrees of wing sweep and three degrees of dihedral.
The prototype Vickers Type 150 B.19/27 (J9131) was flown for the first time on 30th November 1929, at Brooklands.
The two engines used were subject to life restrictions allowing for only 50 hours of flight testing by Vickers, although the aircraft was also shown at the 1930 Hendon Air Display at the end of June 1930. Significant problems were encountered with engine cooling with the engines overheating on the ground.
After initial test flying, new radiators were fitted although the aircraft later suffered a double in-flight engine failure, sustaining significant damage during the resultant forced landing.
During the rebuild a number of modifications were introduced, both to improve cooling and to address handling and stability problems that had been encountered.
Vickers Type 150 Vanox RR Kestrel III J9131 B.19/31 J9131 after rebuild with Kestrel III engines and large wheel spats.
The dihedral was increased to 3.5 degrees, with the fuselage torsional stiffness also being increased. Wheel spats were fitted with a view to reducing drag and a new steam condensing cooling system was also installed when the engines were replaced with 525 hp Rolls-Royce Kestrel III's.
At this stage, the name Vickers Vanox was adopted (by Vickers – but not officially) for the design.
In July 1931, further modifications were made which included a reduction in the wing dihedral to 2 degrees. At this stage, directional instability became much more pronounced. This resulted in severe criticism from the assessors at the Aeroplane and Armament Experimental Establishment (A&AEE) at Martlesham Heath who condemned both the aircraft’s lateral and directional stability. In attempting to solve this problem, the dihedral was further reduced to half a degree and the sweepback of the wing reduced from 12 degrees to 7 degrees. These figures subsequently remained unchanged through the rest of the aircraft’s life.
Vickers Type 150 Vanox Type 195 Pegasus The B.19/27 J9131 in May 1932 converted to Bristol Pegasus engines as the Vickers Type 195.
Problems with cooling the Kestrel engines resulted in a decision to replace them with a pair of air-cooled Bristol Pegasus IM3 radial engines. After this conversion, the Vickers type designation was also changed to the Vickers Type 195, the aircraft returning to Martlesham Heath for trials in this guise on 3rd June 1932.
In its revised form there were no major handling issues raised and the general performance of the aircraft was well received.
One further major modification was introduced in the form of an increased wing-span, resulting in the shift of  two bays outboard of the engines. This increased the span to 85 ft 6 in (upper wing) and 79 ft (lower wing) as well as the ability to increase the fuel load by 114 gallons, resulting in an overall maximum weight increased to 16,400 lb.
The Vickers designation was again changed to Vickers Type 255 and all the modifications were completed by 2nd February 1933.
Vickers Type 150 Vanox Type 225 The B.19/27 in its final form as the Type 225 with Pegasus engines and extended wing span.
By this time however, contracts had been placed for the more successful B.19/27 designs, these being the Handley Page Heyford biplane and the Fairey Hendon monoplane.
The sole Vickers Type 255 continued in RAF service, conducting experimental trials and is reported as taking part in a public display of flight refueling during 1937.
Its last flight with Royal Aircraft Establishment was on 7th January 1938.

Variants & Number Built

One aircraft (J9131) developed to the following:
Vickers Type 150 Flown with Rolls-Royce F.XIV engines, Kestrel III                                        
Vickers Type 195 Type 150 with Bristol Pegasus IM3
Vickers Type 225 Type 195 with increased wing span.

Specification (Type 150/195 Vanox)

Vickers Type 150
Vickers Type 195 (Type 225)
Two 480 hp Rolls-Royce F.XIVS
Two 622 hp Bristol Pegasus IM3
76 ft 6 in
76 ft 6 in (85 ft 6 in)
Maximum Weight
15,400 lb (15,877 lb after rebuild)
16,103 lb (16,400 lb)
Four crew; two Lewis guns, up to 2,200 lb bombs
Maximum Speed
143 mph at 12,500 ft
135 mph at 5,000 ft
920 miles




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