In addition, de Havilland pursued the further development of the type; major derivatives produced include the DH.115, a dedicated dual-seat trainer, and the more advanced DH.112 Venom, a refined variant furnished with a swept wing (instead of the straight wing of the Vampire) and orientated towards conducting ground attack and night fighter operations.
In January 1941, Sir Henry Tizard made an informal approach to the de Havilland Aircraft Company, suggesting that the company proceed to design a fighter aircraft that would harness the revolutionary new jet propulsion technology under development, along with an appropriate engine to go with it.
Its first design, designated as the DH.99, was an all-metal, twin-boom, tricycle undercarriage aircraft armed with four cannon.
The aero-engine designer Major Frank Halford had been given access to Frank Whittle's pioneering work on gas turbines; for the projected jet-powered fighter, Halford decided to proceed with the design of a "straight through" centrifugal engine capable of generating 3,000 lb of thrust, which was considered to be high at the time.
Halford's engine was developed, and emerged as the Halford H.1.
By April 1941, design work on the engine had been completed; a prototype H.1 engine performed its first test run one year later.
The construction of the aircraft exploited de Havilland's extensive experience in the use of moulded plywood for aircraft construction; many design features that were used upon the DH.100, such as the fuselage nacelle and tall triangular vertical surfaces, had been present on the company's preceding Mosquito, a widely produced fast bomber of the war.
The layout of the DH.100 used a single jet engine installed in an egg-shaped fuselage which was primarily composed of plywood for the forward section and aluminium throughout the aft section.