Designed on my phone with no reference, so It only looks roughly similar to the real thing, and definitely shouldn't be expected to perform much like it either. I was going to max out the thrust and call it a D.521 (whose engine was 1030hp; D.520 had 840hp) but the plane was too small to handle the torque cleanly. Also, because it's so small, make sure you pull back well before it reaches 80-90mph as it will otherwise flip forwards and crash. Enjoy!

For those wondering about the history, the D.520 was a French fighter introduced just before the Nazi invasion of France in WWII. It was designed to be an energy fighter superior to the German Bf 109 in maneuverability. This came at heavy cost however, as its engine was underpowered, and the advantage in agility was not enough to make up for it. By the time it went into production, it was far too little, far too late, and as the Dewoitine was the best France had to offer at the time, the French Armée de l'Air was no threat to the German Luftwaffe.
A variation using the same airframe and a Rolls Royce Merlin II engine, dubbed the D. 521, was at one point put into development, but was cancelled before reaching production.