Third prototype NK136 with remotely-controlled barbettes with four 20mm cannons
Evolution of the Vickers Windsor’s Defensive Armament
The intended defensive armament of the Vickers Windsor bomber underwent a notable evolution throughout its development.
Initial Concept (Specification B.5/41): The Windsor was initially conceived as a high-altitude bomber, operating under the assumption that it would be largely immune to enemy fighters at such altitudes. As a result, the original design called for minimal defensive armament, limited to a four-gun rear turret. This suggests a focus on speed and altitude for defense, rather than relying heavily on firepower.
Revised Specification (B.3/42): As doubts emerged about the effectiveness of high-altitude bombing, the Windsor’s specification was revised. The emphasis shifted towards speed and range, with the pressure cabin requirement dropped. This change in operational doctrine also influenced the defensive armament. While the sources don’t explicitly detail the armament at this stage, it’s clear that the focus on a high-altitude, minimally armed bomber was no longer the priority.
Introduction of Remote-Controlled Barbettes: As the design progressed, the Windsor’s defensive armament took a significant turn. Vickers proposed a novel approach: remotely controlled barbettes mounted in the rear of the inboard engine nacelles. Each barbette would house two 20mm cannons, providing a considerable increase in firepower compared to the earlier rear turret concept. This innovative approach aimed to offer greater defensive coverage and firepower without the need for a bulky and vulnerable manned turret.
Armament in the Prototypes: The first two prototypes (DW506 and DW512) were primarily used for aerodynamic testing and did not feature any armament or bomb gear. The third prototype (NK136) initially flew without the barbettes, designated as Type 480, and was later fitted with them in early 1945. This suggests that the development of the remote-controlled barbette system was proceeding in parallel with the overall aircraft design and testing.
Final Intended Armament: By the time the war ended, the intended defensive armament for the Windsor B Mk I had been finalized as:
- Two Browning .303-in machine guns: Fixed, forward-firing in the nose, likely controlled by the pilot or bomb-aimer.
- Two 20mm cannons in each of the two outboard engine nacelles: Mounted in remotely controlled barbettes and controlled from the tail gunner’s position.