Fiat CR.42 DB
Still the fastest biplane aircraft ever built.
The Fiat CR.42 first flew in 1939 with a Fiat A.74 R.C.38 radial engine, and was one of the very last combat biplanes built. With good performance and excellent maneuverability, the CR.42 was the pinacle of biplane fighter design, but the greater speed potential of monoplane fighters had moved to overcome the maneuverability advantage inherent in biplanes. In an attempt to overcome the speed factor the Italian Air Ministry requested Fiat to examine re-engining the CR.42 with the upcoming Alfa Romeo R.A.1000 R.C.41 engine, the licence built DB 601.
As the engine was still in development, a DB 601A was sourced from Germany, and the CR.42 rebuilt arount the new inline engine.
Construction was rapid and the aircraft first flew in March 1941. Although heavier and longer than the standard model, the performance of the new CR.42 DB was impressive; being 90 kph faster and with impressive climb rates and maximum altitudes. An order was placed for 150 aircraft, but due to unavailability of engines - due to slow production and pre-allocation to the Re,2001 and MC.202 - none was ever built and the sole CR.42 DB became a historical sidenote.