The crew forgot to lower the undercarriage on approach. The Il-18 landed on its belly. A fire erupted in the cabin. The main cause of the disaster was the failure of the PIC and the flight mechanic to fulfill the most important functional duties for preparing and performing the landing, determined by the flight manual and instructions for the distribution of duties in the crew during the approach, as a result of which the landing was performed with the landing gear retracted. The immediate cause of the disaster was a fire that broke out in the aircraft as a result of the ignition of the AMG-10 fluid ejected from the hydraulic system from a short circuit in the aircraft wiring. Contributing reasons: a) low level of discipline and educational work in the 65th flight unit; b) lack of proper control over the recruitment and commissioning of this crew, as a result of which two people with poor training ware included in the crew at the same time; c) insufficient demand and poor control on the part of the flight and navigational department of the Moscow Air Traffic Service Administration over the execution of the 65th flight unit of the main documents and instructions on flight safety; d) technical imperfection of the IL-18 landing gear position signalling system, the main drawback of which was the necessity of switching off the horn, which was activated during the aircraft descent from, and switching off the signalling light of the retracted landing gear position when the horn was forcibly switched off.