Variants P.14: Two prototypes built to meet Air Ministry Specification F.7/41. Welkin Mk.I: Single-seat twin-engine high altitude fighter aircraft, 75 built, further 26 aircraft were completed without engines. Welkin NF.Mk.II: Two-seat night fighter prototype, one converted from Mark I.
Variants P.14: Two prototypes built to meet Air Ministry Specification F.7/41. Welkin Mk.I: Single-seat twin-engine high altitude fighter aircraft, 75 built, further 26 aircraft were completed without engines. Welkin NF.Mk.II: Two-seat night fighter prototype, one converted from Mark I.