Israel-Iran Tensions: The Role of GBU-57/B in Potential Strikes

As tensions escalate between Israel and Iran, the next two weeks are crucial for military decisions, particularly regarding the GBU-57/B bomb. This powerful weapon, designed for deep penetration, could target Iran's Fordow nuclear site. With its unique capabilities, the GBU-57/B raises questions about military strategies and the balance of power in the region. This article delves into the bomb's specifications, the significance of the Fordow facility, and why Israel may struggle to execute such a strike without U.S. support. Discover the implications of this advanced weapon in the ongoing conflict.

By Narendra Chaudhary Jun 21, 2025, 15:22 IST

Critical Weeks Ahead in Israel-Iran Relations

The upcoming fortnight is pivotal in the ongoing conflict between Israel and Iran, as the U.S. President is expected to make significant decisions regarding military action. Israeli Prime Minister Benjamin Netanyahu has made it clear that he intends to target Iran's Fordow nuclear facility, regardless of American backing. Analysts suggest that Netanyahu may depend on the U.S. military's advanced GBU-57/B bomb, known for its capability to penetrate deeply buried nuclear sites in Tehran. This raises questions about whether the U.S. is the sole possessor of such a weapon and the depth of the Fordow facility.

Understanding the GBU-57/B

Weighing in at 30,000 pounds (approximately 13,600 kilograms), the GBU-57/B is engineered to penetrate up to 200 feet (61 meters) underground before detonation. Despite Israel's objective to prevent Iran from acquiring nuclear weapons, this bomb is not part of its military arsenal. The bomb is designed in a cylindrical shape, roughly 20 feet long and 2.5 feet thick, making it a formidable non-nuclear option for targeting deep underground facilities. The designation GBU-57/B indicates it is the 57th model in its series, with the 'B' denoting a specific variant.

The Fordow Facility

Located 18 miles northeast of Qom, Fordow is Iran's most sophisticated nuclear enrichment site. Reports indicate that it can produce sufficient highly enriched uranium for a nuclear weapon within days. The facility is situated deep within a mountain, shielded by 260 to 300 feet of rock and concrete, and is equipped with air defense systems. To inflict damage on Fordow, a significant level of penetration is required, and the GBU-57/B is uniquely capable of achieving this, unlike any other conventional bomb.

Israel's Limitations in Targeting Fordow

No conventional bomb can match the GBU-57/B's capabilities. For instance, Israel's GBU-28, weighing 5,000 pounds, is significantly less powerful and cannot reach the depths of Fordow, which is estimated to be between 260 and 300 feet. The GBU-57 can only be deployed by the U.S. Air Force, specifically using the B-2 Spirit stealth bomber, which is designed to evade radar detection and can carry two of these bombs simultaneously, totaling 60,000 pounds. Other nations, including Russia and China, do not have publicly known equivalents to the GBU-57 that are optimized for such deep targets.

Evading Air Defense Systems

The B-2 Spirit stealth bomber, which carries the GBU-57, is engineered to bypass Iran's air defense systems, including those supplied by Russia, such as the S-300. This capability is crucial for accessing heavily fortified sites like Fordow.

Precision and Impact of the GBU-57

The GBU-57 is GPS-guided, ensuring high accuracy even after penetrating deep underground, maximizing damage to subterranean structures.
Its warhead, weighing 5,300 pounds, can incapacitate or destroy critical equipment like centrifuges, even if the facility itself remains intact.

No other nation operates the B-2 bomber, and alternative aircraft, such as Israel's F-15s or F-35s, lack the necessary payload capacity and stealth to effectively deliver the GBU-57.