What for the plane flies over Lipetsk?

This afternoon residents of Lipetsk noticed the plane which is continuously flying over the city. It appeared that it is a civil board. As told GOROD48 the former navigator-researcher, Hera to Russia Vladimir Ivanovich Bogodukhov, over the city passes planned flight of the civil AH-26 plane An-26. It tests systems of take-off and landing approach of civil airfield "Lipetsk", after them maintenance. Such flight can proceed approximately an hour and a half...