The Showdown: GBU-57 - The Weapon That May Crack Iran's Buried Fortresses
- by Gernot Kramper
- 4 Min
Powerful Weapon GBU-57: Designed to Dismantle Iran's Deep Underground Fortifications - High-Powered Bunker-Buster Missile, GBU-57, Claimed to Shatter Iran's Deepest Underground Facilities
The Israeli airforce has gained dominance over considerable areas in Iran, leaving the air defense feeble and unable to hinder its operations. Despite this, Israel has not achieved two crucial war goals: the intact uranium enrichment facilities and the neutralization of the vast stockpiles of drones and missiles. The regime has sheltered these strategically important facilities underground, in buried bunkers and tunnel systems, making them hard to reach.
Deeply buried bunkers are a challenge for traditional bombs, missiles, and long-range weapons such as cruise missiles and rockets. The heavy armor and earth layers above render them largely ineffective. Special "bunker busters" like the German Taurus do not have the required power for deep bunkers, and Israel relies on the SPICE-2000 with a 900-kg warhead, which is also insufficient. The Russians have faced the same issue in Ukraine, with bomb-proof factories from the Cold War era withstanding bombardments.
Breaking the Barriers: Strategies for Hitting the Depths
Several methods exist to crack deep bunkers:
- Giant Surface Explosions: These giant surface blasts mainly affect areas below, acting like a giant hammer blow to shatter structures beneath. Examples include the U.S.'s MOAB (or "Mother of All Bombs") and the Russian "Father of All Bombs" (АВБПМ). However, these weapons are effective only on near-surface targets and don't reach great depths.
- Bombs That Penetrate Ground: These bombs penetrate the ground, explode, and trigger a local earthquake. Examples include the U.S.-made GBU-28 "Deep Throat," which can go through about 6 meters of concrete. However, such bombs have limited effects on deep targets.
- Penetrator Weapons: The third method employs a technique similar to armor-piercing shells. The GBU-57, a weapon with significant hope for many Israelis, adopts this strategy. The massive ordnance penetrator (MOP) can plow through 60 meters of earth or 8 meters of reinforced concrete before exploding and then breaking the bunker's armor. Its 2.4-ton warhead can bring devastation if detonated inside a closed bunker system.
Pushing the Limits: Advantages and Limitations
The GBU-57 is a kinetic energy projectile that burrows due to its high kinetic energy but suffers from its massive weight, making it hard to deploy by combat aircraft. Only strategic bombers like the U.S. B-2 Spirit can carry it, but the B-52 Stratofortress could theoretically do so as well, although the B-2 is preferred due to its stealth capabilities. Israel does not possess suitable heavy bombers, relying on direct U.S. involvement in the war, which is not evident, despite occasional hints from the U.S. president.
However, a GBU-57's penetration depth is not infinite. It cannot reach chambers beneath a mountain, and the effect on sprawling facilities with individual sections separated by shafts and bulkheads is limited. To neutralize Iran's entire arsenal, many attacks would be needed, which is impossible given the limited number of GBU-57s. Targeting symbolically important facilities like Natanz or Fordo could be a viable option.
On September 27, 2024, Israel employed a method similar in effect to the GBU-57 without using the heavy bomb. They attacked a command bunker in Beirut hidden under residential buildings in the Haret Hreik neighborhood. First, they destroyed the above-ground structures with multiple waves of attacks. Then, they flung the rubble with additional explosions to attack the actual bunker. Israel used approximately 80 bunker-busting bombs, likely BLU-109 or SPICE-2000, with 900-kg warheads in this operation, demonstrating the feasibility of such attacks, even in Iran, especially if direct U.S. involvement is minimal.
Insights:
- Methods for penetrating and destroying deep underground bunkers include large and hardened bombs with advanced guidance systems, large payloads of explosives, void-sensing technology, and the capability to burrow through earth or reinforced concrete barriers before detonation.
- The U.S.'s GBU-57 MOP is one of the most advanced weapons for attacking deep underground bunkers, boasting a penetration depth of up to 200 feet (60 meters) and a large explosive payload. However, the limited number of available GBU-57s would significantly constrain their use in a conflict like that in Iran.
- Alternatives to the GBU-57, such as coordinated conventional attacks with multiple bunker-busting bombs and complex military strategies, may also be viable options to disable deep underground facilities.
- Israel's strategic dilemma in penetrating Iran's underground facilities, such as uranium enrichment sites, lies in the inadequacy of their current arsenal, even with innovative weapons like the GBU-57.
- The GBU-57, a promising weapon for many Israelis, can penetrate 60 meters of earth or 8 meters of reinforced concrete, but its finite penetration depth and difficulties in deployment by combat aircraft limit its effectiveness in neutralizing Iran's entire arsenal, especially when direct U.S. involvement is uncertain.
