Very, very much a WIP but something from the Green Isle to be going on with.
The McFarlane F.40/1 was developed in a rush after the events over France in 1940 and later the Battle of Britain. It was realised that the aircraft currently in service were not particularly suited to combating the times in use by the Axis at that time. Both the Netherlands and France had fallen ruling them out of providing new aircraft and the UK was desperately clinging on for its own existence so could not spare Spitfire production.
At the time it was mooted early in 1940 that Spitfire production might be undertaken in Tol Galen but the limiting factor of the unavailability of the Merlin proved a deciding factor against it at the time. (note, TG does produce Spitfires later on, specifically VIIIs and XVIs) As there were no immediate off the shelf options other than the P-40 which was already on order from the USA it was decided to embark on an ambitious scheme to develop and prototype a domestic fighter in under 90 days. This proved to be somewhat over ambitious and it was 115 days before the first F.40 flew. The Allison V-1710 was chosen as the powerplant as the type was already being manufactured in-country for other types under licence. The prototype and early serial-production aircraft were armed with two 13.2mm and four 7.92mm Browning Commercials as no viable cannon armament could yet be sourced, the MG-FF / Oerlikon proving too unreliable.
From late 1940 / early 1941 there was a policy shift away from the split armament leading to a homogeneous battery of four 13.2mm Browning Commercials in the wings whilst the cannon conundrum was solved. Once this was solved cannon started to appear on most variants in one form or another, firstly the 23mm Hispano and latterly the 25 and 30mm were mounted.
As with the Spitfire, clipped-wing models were produced for low-level work to increase roll-rate, most of these were fitted with low-altitude rated V-1710s.
With Merlin production starting to catch up in the UK and licence production under-way in TG and the commonwealth some F.40s were fitted with Merlins, most of the Merlin-powered variants were either PR or high-altitude aircraft making use of the Merlin 64, 70 and 71 with associated cabin-blowers.
The final aircraft produced could be found with either a Merlin or V1710 powering them in the shape of a Merlin 66 or 1710-119 and armed with either 23 or 25mm cannon and 13.2mm Brownings.
There's still some variants to do, naming and proper conventions to be followed and what not and the specifications blurb to be transcribed but that shouldn't be too hard to accomplish.
~Mark.