Gluboky boi

Gluboky boi is a Soviet doctrine of operational art developed by Mikhail Tukhachevsky and complemented with logistics and troop mobilization ideas from V.K. Triandafillov; both derived their ideas from lessons learned in the 1920 Soviet invasion of Poland, commanded by Tukhachesky. The name translates roughly into deep battle, which now includes a variety of operational doctrines. This flavor is strategically defensive, rather than strategically offensive as are blitzkrieg and AirLand Battle. It focused on the counterattack against forces that had penetrated by blitzkrieg, but that were overextending their logistical and infantry support. Where blitzkrieg was more or less continuous, gluboky boi used a "pulsed" sequence of echeloned forces of different composition.

Triandafillov wrote the 1929 monograph, The Nature of Operations of Modern Armies, with special emphasis on mobilization, logistics and pacing. Tukhachevsky extended it especially in the area between large unit tactics and operational art, with special emphasis on encirclement and envelopment.

In executing the enveloping operations it is necessary to face the very

complex problem of how deep the enveloping swing should extend ... [if] the direction imparted to both turning movements is too abrupt it will have the quickest effect on the enemy flanks and rear and will expose his forces, before they are encircled, to a series of strikes.

Organization

The forces were organized into four echelons of corps or army sized units, or equivalent air forces. In Tukhachevsky's doctrine developed while chief of armaments, there were three distinct tank missions, each with a specific tank type designed for it.

1. Aircraft with the mission of destroying enemy formations and gaining local air supremacy
2. Infantry and mechanized mix would engage the enemy front-line forces and develop a penetration.Light tanks would be grouped into N[ieposredstviennoy] P[odierzhki] P[iechotiy], (short range infantry support formations), for direct support of infantry. Breakthrough into successive defensive belts, more than 1.5 km behind the front line,would heavy tanks of the D[alshiy] P[odierzhki] P[iechotiy], or (long range infantry support formations). The Soviets would find a role in WWII for heavy tanks, such as the KV-1 and JS-1 tank.
3. Mechanized and armored formations intent on exploiting a breakthrough and encircling enemy rear formations and logistical centers. These would use the B[ystrochodny] T[anki] (fast tanks). After experience in Spain with the BT-5, the T-34 tank replaced it, and generally had the characteristics of both light and fast tanks.
4. A reserve formation to consolidate the victory

This peacetime theory, and the tank types, were to simplify with operational experience, beginning in the Spanish Civil War.

Movement

One variant emphasized abrupt movement through the enemy's length, in which the attacker destroys the front-line troops through encirclement, and the destroys the reserve through a meeting engagement. Another variant, the deep turning movement, depends, above all, on speed. The encirclement avoids strength and attacks weakness, penetrating until the turning movement can take in both the front line and the reserve. A creative defensive commander might prepare strong forces behind the front lines, expecting to give up depth — anathema to Hitler — but some Germans did do this. General Gotthard Heinrici was known for preparing two successive lines of defenses, and was adept at predicting when the Soviets would launch their typically massive artillery preparations, and he would withdraw to the second line just before they did so, and move back to meet the advancing Soviets.

In both cases, "the depth of the attack is determined by the strength, location, and reaction of the defense. The strength of the defense decides the speed, viability, and feasibility of the attack. For ground forces, this translates to the disposition of the defender's defenses, including maneuver forces, as well as other means of countering an attack."

While there had been trials during the Spanish Civil War, the full doctrine first went into action at the 1943 Battle of Kursk, which remains the largest tank battle in history. Spanish experience showed that the specialized tank designs were less important that had been believed, as lessons learned caused each type increasingly to receive equipment developed for another mission.

At Kursk, Hitler authorized an unprecedented retreat, and cancellation of Operation Citadel, as the Operational Maneuver Group using gluboky boi principles started to counterattack the exhausted blitzkrieg forces.