The aircraft performed a flight from Krasnodar to Moscow on the instructions of the headquarters of the 4th Air Army. Onboard there were 6 crew members and 8 passengers. At the same time, the mission for the flight provided for checking the co-pilot. After 5 hours and 30 minutes of flight, the oil pressure in the right engine began to gradually drop. There was a slight shaking of the engine. The captain decided to continue on one engine. After 10 minutes of single-engine flight, the temperature of the cylinder heads increased to 230-240øC. The captain then decided to make an emergency landing at Yegoryevsk, but decided to go around. When increasing power, the right engine did not react and remained on low throttle. Having flown over the airfield on one engine the aircraft could not gain sufficient speed and altitude. The tail section contacted the roof of a building and the aircraft fell to the ground. The crew and passengers were slightly injured. During the investigation, it was found that the reason for the drop in oil pressure on the right engine was insufficient filling of the oil tanks. There were no malfunctions, the oil consumption did not exceed the norm.