Two-seat Welkin Mk II prototype converted from DX386
Design Modifications of the Welkin NF Mk II
The Welkin NF Mk II, a two-seat night fighter variant, introduced several key design modifications compared to its predecessor, the Welkin Mk I. The primary goal of these modifications was to accommodate a second crew member, radar equipment, and adapt the aircraft for night interception duties.
Fuselage Extension: The most noticeable change was the lengthened front fuselage, extended by 76 inches (1.93 meters) forward of the front spar. This modification provided the necessary space for a rear-facing radar operator’s cockpit behind the pilot.
Radar Installation: To fulfill its night-fighter role, the NF Mk II incorporated a thimble-shaped radome in the nose to house the AI Mk. VIII radar scanner. This radar system, a significant technological advancement, was the first centimetric scanner used by the RAF.
Redesigned Windscreen: The NF Mk II featured a modified windscreen with a lowered and forward-raked arch. This change aimed to enhance the pilot’s forward visibility, crucial for night operations.
One-Piece Canopy: Unlike the three-piece windscreen and sliding hood of the Mk I, the NF Mk II adopted a single-piece, aft-sliding canopy. This modification likely streamlined the design and potentially improved the pilot and radar operator’s field of view.
Structural Reinforcements: The extension of the fuselage necessitated strengthening the fuselage center section structure and skinning immediately aft of it. This reinforcement ensured the structural integrity of the modified airframe.
The initial plan was to convert 60 Welkin Mk.Is to the NF Mk.II configuration, only one prototype (PF370, converted from DX386) was ultimately completed. The second prototype, planned to be converted from DX408, was canceled, along with the production order for 60 aircraft.