Lazarov Laz-9

 

Professor Tsvetan Lazarov, one of the best aircraft designers of Bulgaria, lived through difficult times. The new world order that came after World War 2 was setting up across the world and there was a war going on in the Korean Peninsula. At the same time, the Bulgarian Air Force was heavily cut and purged politically after the war, leaving it short on flight and technical staff. This situation required a large number of pilots, navigators and aircraft technicians to be trained in a short period of time. As pilots and navigators must receive comprehensive and solid combat training, the Lazarov Laz-7 was employed, much to Lazarov's dismay, as a multi-purpose heavier-than-intended aircraft that went from the initial 947 kg (2088 lbs) of the prototype to the 1145 kg (2524 lbs) of the production version, worsening flight characteristics. 

In order to express his concerns about the usage of the aircraft, Prof. Lazarov wrote a letter to the Bulgarian Air Force Command, Metalchem Industrial Association (manufacturers of the Laz-7) and other institutions involved in the manufacturing process of the Laz-7. In this letter, dated at 10th October 1950 he stated that it was unacceptable the further degradation of the flight characteristics of the Laz-7 and suggested to keep the Laz-7 for the initial basic pilot training and have a new aircraft type (namely Lazarov Laz-9) as the multi-purpose airplane to assume those roles not intended for the Laz-7. For this purpose he described the design of the Laz-9 further in the letter.

The Laz-9 was designed around the German Argus As.410 engine, which yielded up to 450 hp of power, due to the fact that many of them were left over in Bulgaria, some of them even unused. The Laz-9 was going to feature a larger, strengthened and expanded fuselage reminiscent of the Laz-7 with a metallic tail unit and trapezoidal wing with TsAGI (Moscow's Central Aerohydrodynamic Institute) designed flaps. Undercarriage was designed as retractable, similar to that of the Yakovlev Yak-9.

Thanks to the more powerful powerplant, the Laz-9 was expected to take additional equipment and even carrying heavier weapons, allowing the optimal performance of additional combat tasks. It was intended to be armed with a single 13 mm (0.5 in) machine gun mounted on the engine, plus two additional 7,92 mm (0,3 in) lighter machine guns placed in the wings. It was designed to carry a payload of up to 400 kg (882 lbs) of underwing bombs, in, either 8 x 50 kg or 4 x 100 kg configuration. 

Apparently Lazarov's letter was ignored, as the Bulgarian Communist regime had already decided to dismantle the Bulgarian aviation industry, following orders from Moscow and the project never went beyond the design stage. 

Sources:

http://www.airwar.ru/enc/other/laz9.html (translated and adapted)