Technical Project “Object 432” , April 1961: The Birth of the T‑64 and Its Key Innovations. Part 1

Andrei Tarasenko

Annotation

The article presents a comprehensive technical and historical analysis of the Technical Project “Object 432” (April 1961) — the prototype that laid the foundation for the T‑64, the first Soviet main battle tank.
Based on archival materials, designer diaries of A. A. Morozov, and specialized engineering publications, the study examines the origins of key innovations that defined the next generation of Soviet armored vehicles.

Particular attention is given to the evolution of the composite hull and turret protection, the development of the automatic loading system, and the implementation of integrated NBC (nuclear, biological, chemical) defense systems.
The paper reconstructs the principal design solutions detailed in the explanatory memorandum of the 1961 technical project, including armament arrangement, crew layout, armor composition, and protection efficiency.

The research highlights the technological challenges encountered during early production — such as design shortcomings of the “cheeked” glacis, turret modifications, and the transition from fiberglass to multi‑layer steel‑ceramic protection — and traces their resolution through the evolution of T‑64A/B models.

The analysis demonstrates that Object 432 became a milestone in armored vehicle development, establishing the architectural and technological framework later used in the T‑72, T‑80, T‑90, and derivative tanks across the world.
The material contributes to the historiography of tank design by combining primary technical documentation with engineering evaluation of structural innovations.

External views of the “ 432” tank with TPDMS and TRLD systems

Development and Design Objectives

At the turn of the 1950s–1960s, Soviet tank‑building faced the task of developing and putting into series production, in the shortest possible time, a new main battle tank capable of operating under conditions involving weapons of mass destruction and significantly surpassing all existing production tanks in its tactical and technical characteristics.

On March 15, 1962, the “ 432” tank №1, still without a turret but ballasted to the design weight defined in the tactical‑technical requirements (TTT), completed its first factory trial run. The second prototype, “ 432” №2, was sent to Kubinka for a demonstration held on October 22, 1962, before the Ministry of Defense and Government leaders (including Khrushchev, Brezhnev, Kozlov, Kosygin, Ustinov, Malinovsky, Yepishev, Chuikov, and others). The vehicle was approved for accelerated introduction into production.

Decree of the USSR Council of Ministers №693‑291 of July 4, 1962, authorizing production of a pilot batch of “Object 432,” was issued even before the demonstration.
In total, six experimental prototypes of “Object 432” were built during 1962–1963, undergoing comprehensive factory and field tests.

By 1964, serial production of the T‑64 tank began according to documentation prepared under the supervision of chief designer A. A. Morozov. Although criticized for initiating series production before formal adoption into service, this step ultimately proved necessary: it enabled broad‑scale trials and operational testing, which in turn allowed continuous refinement of the design.

After modifications and repeated testing, the tank was officially adopted by the Soviet Army under decree №982‑321 of the CPSU Central Committee and Council of Ministers, dated December 30, 1966, which also confirmed its principal performance specifications.

Thus began an entire era in Soviet tank development—one that would determine the evolutionary direction of armored vehicles for decades to come.

The “ 432” tank became the progenitor of a new family of main battle tanks and a pioneer in applying revolutionary design ideas and technologies. On this tank—later designated T‑64—virtually every major Soviet innovation in armored technology was first tested:
• combined composite armor,
• the automatic gun‑loading system,
• the ability to fire guided antitank missiles through the main gun barrel,
• compact side‑mounted transmission gearboxes, and much more.

Like any fundamentally new machine, the T‑64 had to overcome significant difficulties during development and early deployment, gradually eliminating deficiencies and leading the way for successors.

The design principles embodied in the T‑64’s layout continue to live on in the T‑72, T‑80, T‑90, BM “Oplot”, Al‑Khalid, Type 96, Type 99, VT‑1A, and other derivative tanks—many of which still serve worldwide today.

This article presents the key sections of the design justification and explanatory memorandum for the technical project of the medium tank “Object 432,” April 1961.
Compared with the earlier draft design, this version incorporated enhanced protection: the growing calibers of tank guns, widespread adoption of shaped‑charge (HEAT) ammunition, and the need to protect the crew against nuclear effects demanded a fundamentally new approach to tank protection.

In several areas that might raise additional questions, explanatory notes are provided based on quotations and remarks from A. A. Morozov and other specialists in the field.

By mid‑1961, the technical project for the new tank Object 432 had been approved, establishing unprecedented protection, powerful armament, and high mobility for its time. The concepts defined in this project set the course for Soviet tank design for many decades.

The new medium tank “ 432” was created in accordance with Decree №141‑58 of the CPSU Central Committee and USSR Council of Ministers dated February 17, 1961, based on the hull and systems of Object 430.

Compared with both in‑service Soviet medium tanks and the experimental “Object 430,” the new technical design envisioned the following major improvements:

• Increased firepower and fire control efficiency, achieved through installation of a 115 mm smoothbore gun of the “Molot” (Hammer) type, equipped with precise sighting systems and a mechanical loading device ensuring high rate of fire.
• Enhanced protection, capable of defeating armor‑piercing, sub‑caliber, and shaped‑charge projectiles of all then‑current guns up to 105 mm caliber.
• Integrated nuclear and biological crew protection (NBC system).
• Improved mobility, with target maximum road speed up to 65 km/h and average cross‑country speed of 35–45 km/h.
• Reduced overall weight to approximately 34 tons.

  Note: The projected reduction to 34 t was not achieved. The T‑64 tank adopted for service by decree №982‑321s of December 30, 1966 had a combat weight of 36 t.

Firepower and Combat Compartment Layout

The general internal layout of the tank and arrangement of its main compartments remained similar to Object 430, except for a radically redesigned fighting compartment executed under a new scheme.

To increase firing power, the tank was equipped with a 115 mm smoothbore gun D‑68, with an initial armor‑piercing projectile velocity of 1615 m/s. In addition to AP shots, the gun fired HE (high‑explosive) and HEAT (shaped‑charge) rounds.

The D‑68 was similar to the U‑5TS “Molot” gun but included structural changes required by the new turret layout—specifically reduced recoil length (320 mm vs 430 mm), elimination of the folding gun guard, substitution of the elevation mechanism with a manual hydraulic pump acting on the stabilizer cylinder, reduced wedge projection, and a 250 kg overall weight reduction.

The gun was stabilized in two planes using the “Siren” system, designed specifically for this project and offering high accuracy.

To improve stabilizer performance, the turret was inclined 1° forward, allowing the gun to depress up to 6°3′ relative to the horizon.

The sighting complex included a TPDMS combined sight‑rangefinder, capable of both stereo and monocular ranging. Alternatively, the tank could be equipped with a radar rangefinder (system No. 42 project) integrated with a T2S sight.

These advanced aiming devices were expected to greatly enhance firing accuracy; the limiting factor for rate of aimed fire would be the loading process. Thus, manual loading was deemed unacceptable—it would restrict the high cyclic rate required in modern combat.

Consequently, the design devoted special attention to eliminating the loader as a crew member and creating a sophisticated mechanized loading system, capable of holding 30 rounds (75 % of the onboard load of 40 rounds) in the automatic loader carousel.

This decision significantly improved both firepower and fighting efficiency while reducing crew size and internal armored volume, thereby lowering overall tank weight.

Loading Mechanism and Internal Arrangement of the Fighting Compartment

When discussing unused armored volumes in existing tanks, it is worth recalling that in the Object 430, to allow the loader to operate manually while standing, the entire right‑hand side of the fighting compartment—over 2 m³, or approximately 18 % of the tank’s total internal volume—was practically empty.

Therefore, one of the major design challenges of the new layout was to utilize this previously wasted space. The problem was solved as follows:

The loading mechanism was designed for separate‑loading ammunition with a semi‑combustible cartridge case, whose components were significantly smaller than those of a unitary round. This made it possible to accommodate the entire automatic loader system within the hull, arranging the ammunition in a circular conveyor that defined the shape of the redesigned fighting compartment—a cylindrical capsule (turret basket) suspended from the turret ring.

Loading Mechanism

Loading Mechanism

Design of the Automatic Loading Mechanism

The adopted loading mechanism consisted of a rotating carousel conveyor holding 30 rounds, mounted on an internal ring affixed to the turret ring bearing.
The maximum outer diameter of the conveyor was approximately 2000 mm.

Cartridge cases were positioned vertically (base upward) in individual cassettes connected to horizontal trays beneath the floor, which carried the projectiles.

Control of the autoloader was centralized on a gunner’s control panel with three selector buttons, each corresponding to a projectile type. Next to the buttons, round counters indicated the remaining ammunition of each type.

Loading Cycle

Once a type of round was selected, the loading process proceeded automatically through the following steps:

1. The conveyor rotated to align the selected round with the loading axis.
2. The hydraulic loading arm, located beneath the floor, engaged the projectile tray and rotated it upward by approx. 103°, positioning it vertically.
3. The arm then lifted both the projectile tray and the cartridge‑case tray—guiding the movement through a cam path—bringing the two components to the loading line.
4. At that point, the trays opened, and the round was rammed into the gun’s breech by a belt‑type hydraulic rammer.
5. The arm and empty trays automatically returned to their initial positions, ready for the next cycle.

All actuators were hydraulically powered by an independent pump unit. The calculated rate of fire was 8.46 rounds per minute.

Cyclogram of firing from a D-68 cannon with mechanised loading

Spent Case Handling

To prevent the gun muzzle from striking the ground during reloading (an issue discovered on Object 430), the gun automatically elevated to +2° for the duration of the loading cycle.
After ramming, it re‑engaged stabilizer control and returned to the aiming position.

Upon firing, the spent case base (stub) was ejected into a catcher mounted to the gun guard. During the next reloading cycle, the catch was flipped by the loading arm, dumping the stub into a trumpet‑shaped chute that led to a ring collector located at the bottom of the turret basket. The collector could store 30 cartridge bases, which were shifted automatically as new ones were added.

The mechanism’s design also included provision for mechanized replenishment of rounds and cartridge cases into the conveyor during ammunition resupply.

Crew Arrangement in the Turret

The turret crew consisted of two men, seated inside the carousel’s central space (inner diameter ≈ 1650 mm, excluding liner).

• The commander sat to the right of the gun,
• The gunner to the left,
  with a vertical working height of 1200 mm each.

The commander’s station was equipped with a command cupola containing a central day/night periscope Karmine‑3 and two flanking daylight vision blocks identical to the driver’s.

A 7.62 mm coaxial machine gun of the Nikitin system was mounted parallel to the main gun in front of the commander.

To maximize workspace for the turret crew, most auxiliary components not requiring direct access were relocated outside the turret basket.
For instance, the entire hydraulic traverse drive unit of the “Siren” stabilizer was repositioned to the front‑left corner of the hull. The turret traverse itself was driven, via external gearing, through a ring gear cut into the internal turret‑ring bearing.

The gunner retained a manual traverse mechanism with an azimuth indicator, meshing through an internal gear into the fixed turret‑ring flange.

Ammunition Stowage

Ten reserve rounds were stowed in the front‑right hull section, inside the front and rear left fuel tanks.
These could be loaded through the driver’s hatch, and, when needed, retrieved by the turret crew through two access hatches connecting the turret basket with adjacent compartments.
This arrangement allowed the driver to assist in ammunition handling when required.

For configurations with a radar rangefinder, additional specialized equipment had to be installed inside the fighting compartment.
Although this reduced the available free space, it did not significantly degrade crew ergonomics.

Accessibility and Maintenance

Given the isolated design of the fighting capsule, the overall internal layout ensured that maintenance of key systems could be performed from either the driver’s compartment or the engine‑transmission compartment, rather than from inside the fighting area.

Compared to Object 430, the adopted design achieved a saving of over 2 m³ in internal armored volume.
This permitted a straight‑sided hull, interior width 1975 mm, i.e., about 700 mm narrower at the top deck in its heaviest section than Object 430, and reduced the turret’s plan dimensions by about 400 mm, with a 300 mm shorter fighting compartment. These gains enabled a lower overall profile.

Hull height at the driver’s position (“in the clear”) was set at 840 mm, 75 mm less than Object 430, and decreased another 35 mm at the rear of the fighting compartment.
Overall tank height was approximately 100 mm lower than the T‑55.

Design Notes and Technical Analysis

According to the design studies, the specific mass gain due to height increase in a tank is 1.3–1.75 times greater than an equivalent surface‑area increase caused by lengthening or widening the hull. Therefore, a reduction in height offers significant weight savings.

Reducing the internal protected volume also provides mass efficiency, as the space required for the autoloader and its ready rounds is considerably smaller than that needed to accommodate a human loader and his ammunition racks.
In manual‑loading tanks such as the T‑55 and T‑62 (100 mm and 115 mm guns, respectively), the combined volume occupied by the loader and ammunition was 1.5 – 1.7 times larger than that needed for the autoloader and ammunition of later 125 mm‑armed tanks (T‑64A, T‑72).

Effect of Gun Caliber on Firing Rate

The trend toward increased gun calibers and projectile weights led to the adoption of separate‑loading ammunition, which unavoidably reduced manual loading speed.
For comparison:

• The 85 mm gun of the T‑34‑85 offered a firing rate of 6 – 8 rds/min,
• Whereas 122 mm guns on heavy tanks managed only 1.5 – 2 rds/min.

The loader’s physical capabilities became the limiting factor in achieving higher rates of fire. Manual loading is the most physically demanding operation in a tank crew’s combat workflow, performed under cramped conditions with near‑maximum muscular effort. As fatigue accumulates, the loading cycle lengthens.

For example, simulating the manual loading of a 125 mm gun (projectile 25 kg, charge 15 kg) showed that:

• The first two rounds were loaded within one minute,
• The fifth and sixth — 1.5 minutes,
• The ninth and tenth — nearly two minutes.

Thus, by the tenth round the manual loading rate had dropped by half.

In contrast, the automatic loader achieved 8 or more rounds per minute, maintaining a consistent cycle throughout combat engagements [2].

Entry from A. A. Morozov’s Diary – March 2, 1962

“Today P. I. Barannikov (NII‑21), S. N. Razumovsky, and E. P. Babukhin (NII‑6) arrived regarding the ‘D‑81’ gun. We reviewed two cartridge designs: a unitary round (mass 39 kg, length 1170 mm) and a separate‑loading round weighing 32 kg. Colonel Khokhlov stated that the military would not accept a 40‑kg unitary round for the D‑81.”

Diary Note – April 18, 1961

“We returned again to the question of future tank armament. We had already discussed this back in June 1958, then under a wave of enthusiasm for rocket projectiles. Gun artillery was dismissed as obsolete and ‘dead.’ To keep it from rising again, they set a requirement for muzzle velocity of 3000 m/s—a target obviously unattainable—after which the project was shut down.
Three years have passed, and no viable tank rockets have been created, so the gun is quietly being resurrected.”

“Thanks to those who continued work on the ‘Molot’ and ‘Rapira.’ In general, the artillery plants accomplished little; as a result, our armored forces stagnated, and meanwhile the Americans caught up by developing the M60. I remember how three years ago everyone made bold promises—shortened deadlines, built experimental bases, adopted sound decisions—but nearly all rocket projects were closed. We were left with nothing. There is still no rocket system capable of competing with the gun.”

“For tank armament, the main priorities are: high muzzle velocity, long point‑blank range, and high rate of fire. Tank duels at long ranges should be avoided—that’s the role of surface‑launched rockets and aviation. The tank is a close‑combat weapon, and from the ‘Molot’ gun we must extract the maximum muzzle velocity through new propellants and physical principles.”

Protection Systems: Armor, Anti‑Cumulative Structure, and NBC

Protection scheme for tank ‘432’ against cumulative and armour-piercing shells.

Schematic diagram of the radiation protection system for tank ‘432’. 

General Principles

Diagram of “Object 432” protection against shaped‑charge and armor‑piercing projectiles.
Diagram of “Object 432” protection against radiation.

The growth of tank gun calibers and projectile velocities, the introduction of sub‑caliber penetrators, and the widespread use of high‑efficiency HEAT (shaped‑charge) warheads, coupled with the urgent requirement to provide biological shielding for the crew from nuclear radiation, dramatically complicated the problem of developing adequate protection.

To counter all these hazards simultaneously, the designers abandoned the concept of simple monolithic armor and introduced a composite, integrated (multi‑layer) protection system, consisting of:

• armor steel, primarily resisting and destroying kinetic (AP and sub‑caliber) projectiles;
• anti‑cumulative energy‑dissipating layers of relatively low‑density materials with large thickness but much lighter than steel;
• special anti‑radiation materials, ensuring biological shielding when combined with the armored structure.

Depending on surface geometry, slope angles, and spatial constraints, different combinations of these components were analyzed. The following arrangements were adopted as optimal. 

Hull Armor Layout

·        Upper glacis plate: mounted at 68° from the vertical, of composite structure, total thickness 220 mm.
It consisted of an outer steel armor plate 80 mm thick and an inner fiberglass‑reinforced plastic (FRP) layer 140 mm thick.
Against a horizontally acting shaped‑charge jet, the upper glacis was equivalent to a ≥ 450 mm steel plate.
The chosen FRP thickness simultaneously ensured reliable radiation protection, exceeding the specifications in the TTT.

·        Side armor plates: vertical, 80 mm thick rolled steel, protected externally by spaced screens located at an offset of approx. 1900 mm from the sides under an impact angle of 20°.
These acted as stand‑off shields against HEAT munitions.

·        Front roof plate: 45 mm armor steel, providing resistance to blast overpressure and contributing to radiation shielding.
It included lateral infolded edges (“cheeks”) inclined 78° 30′ from vertical.

·        Rear turret‑deck area: 20 mm armor; engine compartment roof: 16 mm sheet steel.

·        Hull floor: 20 mm armor; step‑height 190 mm (vs. 208 mm on T‑55) with slope 30° to vertical.

All other elements met or exceeded the protective level of the T‑55.

Biological Protection of the Driver’s Compartment

Crew radiation protection was focused primarily on the driver, whose position—centrally along the longitudinal axis—offered optimal field of view and facilitated local shielding.
Main protective elements included:

• The 140 mm FRP upper glacis layer,
• Additional polyethylene lining on hull sides, roof, and hatch cover (the latter being 45 mm armor steel),
• A lead shield attached to the underside of the hull beneath the driver’s seat.

The spaces between vision periscopes were lined with polyethylene; the optical prisms themselves were made of heavy flint glass (type T8‑5).
Three periscopes formed a panoramic assembly providing a 152° horizontal field of view, with increased vertical and horizontal angles for each periscope.

Due to the increased thickness of the driver’s hatch (now 90 mm total, compared to 40 mm on Object 430), a 65 mm floor recess was stamped in the hull under the driver’s position, keeping his seating height (“in the clear”) at 872.5 mm (versus 861 mm on Object 430).

Additionally, the front group of fuel tanks, which were consumed last, and the four accumulator batteries on the left side served as supplementary shielding.

Driver’s Periscope Installation

Turret Armor

Analysis showed that, for turret shapes with complex varying slopes, the use of fiberglass as an anti‑cumulative layer was impractical. Therefore, two optimal composite turret variants were considered:

Variant I – Steel Casting with Ultraporcelain Inserts

A cast‑steel armor shell with embedded ultraporcelain blocks, base horizontal thickness ≈ 420 mm.
According to calculations, the weakening of cumulative jet penetration by porcelain (~ 10 %) rendered this equivalent to ≈ 450 mm RHA (Rolled Homogeneous Armor) against HEAT attack.

Variant II – Layered Cast Turret with Aluminum Jacket

A turret consisting of:

• an inner cast‑steel shell,
• an aluminum anti‑cumulative jacket (poured after steel casting),
• an outer thin steel cladding over the aluminum.

Total wall thickness ≈ 500 mm, equivalent to ≈ 460 mm steel vs. shaped charges.

Both variants yielded a weight saving > 1 ton compared with a homogeneous cast‑steel turret of equal ballistic resistance. Final selection was to be made following manufacturability trials and live‑fire tests.

Variant  I – Steel Casting with Ultraporcelain Inserts

Variant II – Cast turret consisting of a steel armour base, an aluminium anti-cumulative jacket (filled after casting the steel body) and external steel armour plating.

The total maximum wall thickness of this turret is ~500 mm, equivalent to ~460 mm of anti-cumulative protection.

Turret Roof and Additional Elements

The roof was a one‑piece stamped plate, 45 mm thick, ensuring adequate radiation shielding and resistance to direct shell bursts.
The forward roof section incorporated a cast armor housing for the head and main tube of the rangefinder sight (or, in the radar‑rangefinder version, the housing was omitted).

The turret rear and remaining elements provided protection not inferior to the T‑55.

Biological Protection of the Turret Crew

The two‑man turret crew, enclosed above by the turret and below by the cylindrical fighting capsule, benefited from local shielding due to the large armor masses of the turret front.

In this area, a polyethylene liner 10–20 mm thick was sufficient; its thickness increased to 40 mm near the transverse axis of the turret and to 60 mm across the rear zone.
The roof included a 50 mm polyethylene layer, while the lower section of the crew positions was lined with 30 mm polyethylene along the inner wall of the capsule.

The commander’s seat was designed to lower automatically at the moment of an explosion to ensure head protection.

Integrated Protection Coverage

According to design calculations, the adopted configuration provided protection of the following projections:

• upper glacis plate of the hull,
• turret front within an 80° frontal arc,
• hull sides up to 20°,
• turret sides up to 40° from the longitudinal axis.

Equivalent resistance:

• to armor‑piercing projectiles: ≈ 330 mm of homogeneous steel,
• to HEAT jets: ≈ 450 mm steel equivalent along the horizontal jet direction.

This protection was rated to defeat:

• a 100 mm blunt‑nose AP projectile at V₀ = 1000 m/s (except for hull sides, Vimpact ≈ 940 m/s);
• an 85 mm copper‑liner HEAT projectile;
• a 105 mm HEAT and APDS shell from the British M68 gun at a distance of 1000 m.
  (The latter data were theoretical estimates subject to verification.)

Protection Against Nuclear Radiation

The achieved protection values against penetrating radiation from a 30 kt nuclear explosion required approximately:

• 560 kg of polyethylene and lead, and
• 565 kg of fiberglass.

This configuration met TTT requirements, ensuring a radiation attenuation factor of ≥ 15, allowing the crew to survive safely at 900–1000 m from ground zero with a dose not exceeding 200 rem.

Consequently, the biological protection would reduce the fatality zone area by 40–45 % compared to an unprotected tank.

The system further provided an attenuation factor of 18 for residual radiation on contaminated terrain, enabling the crew to remain in an area with 300 R/h background for up to 12 hours within the same 200 R total dose limit.

I. Protection against armour-piercing and shaped-charge projectiles

    II. Anti-nuclear protection 

Note: Object 432 became the first production tank equipped with composite armor protection for both the hull and turret.
Naturally, the introduction of this new concept was not without initial problems.

The design of the upper glacis with “cheeks” (angled side extensions) proved unsuccessful.
From the diaries of A. A. Morozov:

22 December 1965 — Radus‑Zenkovich: “The ‘cheeks’ do not protect the tank against shaped‑charge projectiles. They must be removed.”
26 February 1966 — “…The ‘cheeks’ cause turret jamming; they must be eliminated.”

As a result, additional deflector‑shields (“eyebrows”) were installed on the cheek areas to prevent ricocheting projectiles from striking the joint between the hull and turret.
Later, the “cheeks” were entirely removed, and the hull glacis was replaced by a flat plate design.

At the same time, the driver’s three periscopic vision blocks were replaced with a single wide‑format periscope.

The original armor configuration described in the technical project — 80 mm steel + 140 mm fiberglass laminate — was later replaced by a modified layout, consisting of:

• rear backing plate 20 mm steel,
• 80 mm steel outer plate + 105 mm STB (fiberglass) + 20 mm steel inner backing.

A solid fin‑stabilized projectile, when penetrating fiberglass laminate, does not fracture or deform in the same way as it does when striking steel armor.
Tests of three‑layer barriers (steel + fiberglass + steel) showed a sharp increase in resistance:
the increment of equivalent protective thickness (Δυₚₖₚ) per unit of added material was 2–3 times greater than that achieved by simply increasing the thickness of a homogeneous steel plate.

Therefore, under equal weight conditions, a three‑layer barrier exceeds a single‑layer steel plate in protection efficiency.
This occurs because the rear steel plate is impacted by a deformed projectile, partially destroyed after passing through the first steel layer, having lost both velocity and the original shape of its nose portion.
In multi‑layer structures, the fiberglass’s resistance to penetration rises sharply due to the additional steel backing support [3].

In serial production, the T‑64 adopted the second turret variant, with an aluminum anti‑shaped‑charge filler.
This production turret had a considerable overall thickness—about 600 mm—which reduced the crew’s internal working space.
(From A. A. Morozov’s diary: “The tank commander becomes fatigued and has no space to use a map.”)

The refinement of the ultra‑porcelain‑insert turret (later using spherical inserts) was delayed.
By the start of serial production of Object 434, manufacturing continued with a turret containing inserts of high‑hardness steel.
It was later replaced by a turret with corundum balls (introduced on 1 January 1974), which became the standard for the T‑64A and T‑64B main production series until completion [4].

До появления современных систем управления огнем небольшая лобовая проекция играла важнейшую роль в защите танка.

References

1. Tanks and People. Diary of the Chief Designer A. A. Morozov / compiled by V. L. Chernyshev. – Kharkov : KHITV Press, 2007.
2. Influence of Gun‑Loading Automation on the Overall Properties of the Tank. Vestnik of Armored Vehicle Engineering, No. 1, 1981.
3. On Certain Regularities Determining the Protective Properties of Three‑Layer Barriers under Fire from Solid Fin‑Stabilized APDS Projectiles. O. I. Alekseyev, Cand. of Tech. Sci., I. I. Terekhin. Issues of Defense Technology, Series XX, Issue 63, 1976.
4. Improvement of Tank Turret Manufacturing Technology. L. T. Ilinkova, M. G. Kovriga, G. A. Chikalenko. Vestnik of Armored Vehicle Engineering, No. 2, 1982.
5. Main Battle Tank T‑64: 50 Years in Service / Vasiliy Chobitok, Maksim Sayenko, Andrey Tarasenko, Vladimir Chernyshev. – Moscow: Yauza‑Catalogue, 2016. – 160 p.