The Ilyushin 12P, registration CCCP-L1313, was released from the ARB-400 facility at Moscow’s Vnukovo Airport following repairs. A test flight was planned, which departed at 15:35 hours, despite the weather being below minima due to low clouds and poor visibility. With a malfunctioning radio compass the flight became lost. Bearings were supplied but the accuracy was influenced by the low altitude of the aircraft. The controller advised the crew to carry out a gear-up landing, but the crew insisted on landing at Vnukovo. Visibility was still very poor (200-300 m) and several flights were diverted from Vnukovo to other airfields. Having finally located the airport, an approach was flown at about 19:30 but the airplane was too far to the left of the runway and a go around was performed. The controller then refused another approach and directed the flight to an alternate airport at Klin, to the northwest of Moscow. The flight crew was unable to locate Klin and flew back to Vnukovo, despite several attempts by the Vnukovo controller to direct them to Klin. An approach to Vnukovo was then allowed. During the final approach the right propeller cut the top of a radio communications tower. The aircraft entered a descending right turn, collided with trees and broke up.