A defect in the Soviet gyroscope has been found in the 'Oreshnik' rocket, causing deviations of tens of kilometers
The analytical company Dallas Analytics published materials from internal correspondence of Russian defense companies, which indicate that the ballistic missile and satellite system (BRSD) 'Oreshnik' suffers from a serious defect in its navigation subsystem. A key element is the gyroscopic block GU-503, developed during the Soviet era and adapted for modern missiles.
The gyroscope is responsible for determining the missile's position in flight; a deviation of half a degree at hypersonic speed can lead to a shift in the impact point by several dozen kilometers. In a letter dated March 18, 2025, the company AO 'MZP' informed the customer that serial production of GU-503 has been discontinued, and the equipment for its adjustment, developed in the early 1970s, has almost completely failed and cannot be replaced.
The lack of the ability to calibrate the gyroscope is confirmed by the examination of the debris of the 'Oreshnik', shot down over Ukraine, where the blocks were found to be marked with the year 2025. This indicates that the development of a modern replacement has not been realized.
According to analysts, pressure from the country's leadership, demanding accelerated commissioning, forced manufacturers to abandon standard quality control procedures. As a result, in May 2026, the 'Oreshnik' missile fell on a residential building in Bila Tserkva, deviating from its declared target — a cargo airfield.
At a press conference after the incident, the President of Russia stated that hitting a civilian object was 'for the convenience of observing accuracy' of the combat blocks, thereby acknowledging that the system is still in testing mode, despite previous statements about the start of mass production.
Experts conclude that the identified navigation defect undermines the declared capabilities of the 'Oreshnik' and may become a factor influencing the assessment of NATO's missile defense strategies.
Source: The Insider
