KO decree #428 instructs Kirov Factory to make a series of design and technological changes to the KV tank starting on March 1st, 1941.
A detailed investigation of the changes revealed that:
- The changes require redesigning the entire vehicle, some of which require externally produced assemblies, not yet delivered to the factory, as some have not reached prototype stages, let alone mass production.
- The requirements for new parts are not compatible with the ability of the factory's parts suppliers' output, and ignore the current stages of readiness for mass production:
- By 1941, 200 model 1940 hulls and turrets were required of Izhor factory, which is greater than how many vehicles we assemble in four months.
- The installation of a new commander's cupola and an F-34 gun require the redesign of the turret, and a complete rearrangement of the ammunition rack, gun mount, crew placement, and the design of many large components in the vehicles. Blueprints will only be passed to Izhor factory on February 1st, 1941, for the production of a first sample to be approved by ABTU and AU.
For mass production of this new turret, Izhor factory needs many new complicated stamps, instruments, and devices. By estimates of Izhor factory, supplies of new turrets can start no sooner than July of 1941.
- According to KO decree, trials of a 700 hp engine must be finished by March 15th, 1941. Preliminary estimates indicate that the production, correction, and adaptation of the engine for mass production will take no less than four months.
Aside from this, as a result of the increased power, Kirov factory needs to perform investigations in the area of strengthening components and improving cooling.
- The decree requires the possibility of installing a flamethrower with a range of 90 meters and reservoir for 10-12 shots. Kirov factory cannot do this, since according to our data, no such flamethrower exists or is currently in development.
- The decrease in mass form 46 tons to 42.5 tons with the simultaneous increase of warranty range from 2000 to 6000 km, increased ammunition capacity, installation of a flamethrower and more powerful engine requires the increase of robustness of parts and mechanisms along with a reduction of their weight, which requires redesigning many components.
- According to the Chief of Radio Production, the installation of a KRSTB radio can be achieved no sooner than July. Additionally, according to a letter from the supplier, the dimensions of the device have not yet been finalized.
- The requirement for installing an optical sight on the radio operator's machinegun cannot be satisfied, as optical sights for machineguns are not produced, and the PJa sight is available in small amounts and has not yet been adopted by the army.