The T-80 is a glaring lesson in why heavily-armored tanks can hide major weaknesses. Once considered a premium tank by the Russian military establishment, T-80s suffered savage losses to lightly armed guerrillas during the First Chechen War. The tank’s reputation never recovered.

It wasn’t supposed to be this way. The T-80 was the last main battle tank to come out of the Soviet Union. It was the first Soviet tank to mount a gas turbine engine, giving it a top road speed of 70 kilometers per hour and an efficient power-to-weight ratio of 25.8 horsepower per ton.

This made the standard T-80B one of the most nimble tanks to come out of the 1980s.

The Chechen rebels’ combat prowess–and poor Russian tactics–was more responsible for the T-80’s losses than the inherent design. Though, it did have one major flaw. But in the end, it was too expensive and guzzled too much fuel. The Russian military grew to favor the more economical T-72 series instead.

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The T-80 was an evolution over its predecessor, the T-64. As the most modern tank design of the late 1960s and early 1970s, the T-64 was a departure from the Soviet penchant for simple armored vehicle designs, such as the T-54/55 and T-62.

For instance, the T-64 was the first Soviet tank to replace human loaders with mechanical autoloaders, reducing the crew from four to three. The T-64’s second trend-setting innovation was the introduction of composite armor, which layered ceramics and steel together to provide superior resistance compared to only steel.

Further, the T-64 had lightweight, small diameter all-steel road wheels in contrast to the large, rubber rimmed ones on the T-55 and T-62.

The first mass produced variant, the T-64A, mounted the huge 125-millimeter 2A46 Rapira main gun, which was so popular that it came included on all subsequent Russian tanks … up to the T-90. Remarkably, the T-64A packed all of this potential into a petite 37-ton package–relatively light for a tank of this size.

But as marvelous as these innovations were, the T-64 had a sensitive 5TDF engine and unusual suspension–both prone to breaking down. As a result, the Soviet army deliberately assigned the tanks to units stationed close to its manufacturing plant in Kharkov.

Even worse, rumors circulated that the T-64’s new autoloader chomped off the arms of crew members who strayed too close. It’s a plausible scenario given the T-64’s tiny internal space.

While fixing the T-64A’s automotive maladies, the Soviets developed an interest in developing a new tank with a gas turbine engine. Gas turbines have high acceleration and an efficient power-to-weight ratio, can start quickly in cold weather without prior warm-up–a necessity in Russia’s frigid winters–and they’re lightweight.

On the downside, gas turbines guzzle fuel and have higher susceptibility to dirt and dust owing to their voracious air intake compared to conventional diesels.

The original base model T-80 didn’t enter active service until 1976–much later than planned. The Soviet tank industry had its hands full working out the T-64A’s kinks and gearing up for producing the T-72 as a cheaper backup option. At the same time, the Soviets were building more T-55s and T-62s for Arab allies which had lost hundreds of tanks during the 1973 Yom Kippur War.

The early-model T-80s also had their problems. In November 1975, the USSR’s then defense minister Andrei Grechko blocked the tank’s production because of its wasteful fuel consumption and few firepower advancements over the T-64A. Five more months passed before Grechko’s successor, Dmitriy Ustinov, authorized the new tank to go into production.

The original T-80’s production line continued for two years–not long–as it was already outclassed by the T-64B tank, which featured a new fire control system that could fire 9M112 Kobra missiles from its main gun. More serious, the T-80 was nearly three-and-a-half times more expensive than the T-64A.

The T-80B succeeded the baseline model in 1978. As the most advanced “premium tank” in the East, the Soviets beginning in 1981 assigned most T-80Bs to its highest risk garrison–the Group of Soviet Forces in Germany.

Its high speed earned it the nickname “Tank of the English Channel.” In Soviet war game calculations, T-80Bs were able to reach the Atlantic coast within five days–assuming that they didn’t run out of fuel.

This new variant borrowed from the T-64. In addition to firing conventional sabot, shaped charge and anti-personnel fragmentation shells, the T-80B’s 125-millimeter 2A46M-1 smoothbore gun could launch the same 9K112 Kobra missiles.

Since this anti-tank guided missile was considerably more expensive than regular tank shells, the tank only carried four missiles compared to 38 shells. The missiles were intended to swat down attack helicopters or ATGM-capable vehicles beyond the range of the T-80B’s conventional gun rounds.

A coaxial 7.62 x 54-millimeter PKT and 12.7 x 108-millimeter NSVT Utes machine gun for the commander’s cupola rounded off the tank’s anti-personnel weapons.

While the T-80B boasted advanced composite armor, it had even greater protection through its Kontakt-1 explosive reactive armor, or ERA. Arranged in the same horizontal layers as late production T-72A tanks, ERA-equipped T-80Bs were called T-80BVs.

In 1987, the T-80U succeeded the T-80B in production, if not absolute numbers.

Externally, the T-80U mounted Kontakt-5 reactive armor. This was an improvement over Kontakt-1–which used an add-on array of explosive filled shingles. Instead, Kontakt-5 was a factory applied set of plates pointing forward to maximize the deflection angle of incoming rounds. Kontakt-1 was only useful against shaped charge warheads, while Kontakt-5 added resistance to kinetic energy sabot rounds as well.

Internally, the T-80U traded the T-80B’s 1A33 fire control system for the more advanced 1A45. The engineers swapped out the Kobra missiles with the laser-guided 9K119 Refleks guided missile–a more reliable, longer range and harder hitting weapon. T-80Us crammed in seven more rounds of 125-millimeter shells than the T-80B.

But the T-80U didn’t last long in production. Its new GTD-1250 turbine was still too fuel hungry and maintenance heavy. In its place came the diesel powered T-80UD. This represented the last T-80 variant to be produced in the Soviet Union. It was also the first of its kind to see action outside of a training school … if “action” meant blasting tank shells into the Russian parliament to settle the October 1993 constitutional crisis.

The December 1994 separatist war in Chechnya was the first action for the T-80 where the shooting was going both ways … and it was an epic disaster.

When rebels in Chechnya declared their country’s independence, Russian president Boris Yeltsin ordered troops to bring the former Soviet republic back to the fold by force. These troops took T-80Bs and BVs with them. The soldiers had never trained with the T-80 before. Ignorant of the new tank’s gluttony for fuel, they ran their engines dry while idling.

The Russian advance into the Chechen capital Grozny was a near massacre for the invaders–nearly 1,000 soldiers died and 200 vehicles were destroyed from Dec. 31, 1994, to the following New Year’s Day evening. As the most advanced vehicle in the Russian assault force, the T-80B and T-80BVs suffered horrific losses.

While impervious to direct frontal hits, dozens of these tanks were destroyed in catastrophic explosions, their turrets blowing off after sustaining multiple strikes from the Chechen rebels’ RPG-7V and RPG-18 rocket launchers.

It turned out–the T-80’s Korzhina autoloader had a fatal design flaw. The autoloader stored ready propellant in a vertical position, with only the tank’s road wheels partially protecting it. RPGs striking the T-80 in the sides above the road wheels were likely to set off the propellant, resulting in the tank’s explosive decapitation.

In this respect, the T-72A and Bs–which received the same kind of punishment–had a marginally higher probability of surviving flanking strikes because their autoloaders stored propellant in a horizontal position below the rims of their road wheels.

A second major fault of the T-80, like previous Russian tanks, was minimal gun elevation and depression. The tank’s gun could not fire back at rebels shooting from upper story rooms or basements.

To be fair, T-80 casualties were more likely the fault of ill-prepared crews, inadequate training and disastrous tactics. Such was the haste of Russia’s rush to war that T-80BVs entered Grozny without the explosive filler in their reactive armor panels, making the armor useless. It was even alleged that some soldiers sold off the explosive inserts to supplement their salaries.

The Soviet army had long forgotten the hard lessons of urban warfare from World War II. During the Cold War, only Spetsnaz commandos and the Berlin garrison had trained for serious city fighting. Expecting little resistance, Russian forces drove into Grozny with infantry buttoned up inside their BMP and BTR transports. Their commanders got lost because they didn’t have proper maps.

Since Russian soldiers were reluctant to exit their transports and clear buildings room by room, their Chechen adversaries–who knew the weaknesses of Russian vehicles from Soviet-era conscription–were free to turn the tanks and other armored vehicles into crematoriums.