On February 26th, engineer A.A. Mikulin from the OAT technical bureau arrived at the factory, and began inspection of the air cooled 30-35 hp engine and transmission.
The device was in the final stage of assembly. All engine systems were examined, notes were made, and individual components were altered. The engine worked for 10 hours in total without load, from 1200 RPM to 2000 RPM. The engine then worked for 3 days straight with load. After that, the engine worked at 15-26 hp with breaks for 6 hours. During those last trials, the air temperature was 15 degrees on intake and 52 degrees on exhaust. Due to a lack of instruments, the factory could not measure the speed of air flow at various points. Use of oil and gasoline has not been measured. This does not allow for any judgement to be made regarding the engine's usage characteristics, or the possibility of increasing engine power without overheating the cylinders. As for the power reserve, the engine operated at 26 hp and 1800 RPM when the throttle was open to a third. The calculated 35 hp power is guaranteed.
Preliminary trials show that the engine, after longer general trials and removal of discovered defects, can enter service as a reliable and functional device.
After the factory trials, I consider it rational to stage longer trials at the NAMI automotive department, where all characteristics of the engine will be discovered, and optimal operating mode be found, as it is possible that the Sirokko cooler will work better at higher RPM.