Functionally, a Hawker Tempest redesigned to take the Rolls-Royce Eagle 46H eagle making ~4,000 hp+.
It was expected to be able to reach a top speed of 508 mph/819 kmh at 6,069 m with an eye-watering climb rate of 1951 ft/min or 32.51 m/s.
There’s a thread on the Secret Projects forum that has a bunch of interesting info on it, and it’s one of my personal favourite prop designs.
The S13 and B26 (Modified Fokker G.I Mercury’s ordered by Sweden but as the Netherlands were invaded the order had to be cancelled.)
Its funny, the B26 was a replacement order for the Bréguet 693 attack aircraft previously ordered from France that became inaccessible after France got invaded, interesting for the replacement to suffer the same fate.