Caproni Ca.165 - Testing and Evaluation

Testing and Evaluation

At Guidonia, the aircraft was tested like the many other fighters present for evaluation. However, it was only tested against the Fiat CR.42 Falco, the only other biplane. In mock-up fights the Ca.165 outperformed the CR.42, thanks to the superior aerodynamics and available power. Despite this, the aircraft was rated inferior as the CR. 42 was more maneuverable and employed a reliable powerplant while the Caproni engine was experimental and had poor reliability. However, the Ca.165 was declared the "winner" of the mock fights, so General Valle ordered 12 examples on 2 September 1939, although the order was cancelled on 11 October 1939 and changed to 12 Caproni F.5s. This production shift was made even though it involved the payment of a penalty.

The Ca.165 was comparable in useful load (570 kg/1,257 lb vs. 575 kg/1,268 lb) and weapons (2 × 12.7 mm/0.5 in, 1 × 7.7 mm/0.303 in) to the CR.42, but it was 200 kg (441 lb) heavier with less wing surface, so it had wing loading of 113 kg/m compared to 99 for the CR.42; and that, coupled with the less effective controls, made the Ca.165 less agile. Despite these shortcomings, the Ca. 165's minimum speed was lower (114 km/h/71 mph vs 122 km/h/76 mph), allowing for shorter takeoff runs and slightly better low-speed performance.

The Ca.165 had a very slim and small fuselage, but was heavier than the CR.42, which was due, arguably, to the different engine and construction. The Caproni was not really a 'turning fighter', but given the limits of biplanes, was more of an 'energy fighter' with more pronounced capabilities in speed than turning (as was emphasized by the test pilots). An improved version was designed to address the maneuverability limitations, but the development was interrupted. It was built with non-strategic materials (steel and wood mainly), so it could have been an advantage in the war in terms of strain on the materials industry, but given the type of engine, it is unclear if it was an economically practical aircraft.

Caproni tried other ways to improve this powerful biplane, first with the P.XI 746 kW (1,000 hp) radial engine (the same as the Reggiane Re.2000), then with Isotta Fraschini L.170 746 kW (1,000 hp) liquid cooled powerplant, and the redesigned Ca.173 (with sesquiplane wing). None of these proposals were successful, at least not enough to pique the interest of the Regia Aeronautica. In any case, both engines were far from being sufficiently reliable and were never adopted in large numbers by the Italian air force.