B-2 Spirit bombers deploy GBU-57 Massive Ordnance Penetrators
As reported by Tom Cooper, an Austrian aerial warfare analyst and historian, on June 22nd, 2025, at 02:35 local time, the United States launched a series of airstrikes targeting multiple Iranian nuclear sites. According to official Pentagon reports, the operation was carried out as follows:
Fordow Nuclear Facility: Six B-2A Spirit stealth bombers of the US Air Force dropped a total of twelve GBU-57B Massive Ordnance Penetrators. These bombs, each weighing 30,000 pounds (13,607 kg), are specifically designed to penetrate deep underground before detonating, making them suitable for facilities like Fordow, where sensitive nuclear infrastructure is buried beneath layers of reinforced concrete and soil. Local reports described minor fires and “ground shaking,” but no large-scale visible destruction was observed. Tom Cooper notes that the likely aim of the bombs was the entrances and immediate operational areas rather than the deepest core of the facility, given its extreme depth.
Natanz Nuclear Facility: A single B-2 Spirit delivered two GBU-57Bs against Natanz. The Natanz facility has a core buried approximately 30–60 meters underground, and Cooper observes that the penetration depth of these bombs makes it plausible that critical parts of the infrastructure were damaged. Unlike Fordow, Natanz’s depth is within the effective range of the MOPs, increasing the likelihood of structural impact.
Esfahan Nuclear Facility: Surface enrichment facilities in Esfahan were targeted by thirty Tomahawk Land Attack Missiles launched from the USS Georgia (SSGN-729), a former nuclear ballistic missile submarine converted to carry these precision missiles. Local observers reported limited visible damage, consistent with the fact that these targets are less fortified and primarily above ground. Cooper notes that this action complements the B-2 strikes by disrupting operational capacity at multiple locations simultaneously.
Iranian Retaliation Against Israel
In response, the Islamic Revolutionary Guards Corps Air & Space Force (IRGCASF) launched a series of ballistic missile attacks against Israel. Tom Cooper details that two waves of missiles struck with a total of 27 projectiles: 22 in the first wave and 5 in the second. Israeli reports indicate one impact near Haifa and 11 injured.
The missiles targeted strategic sites, including Ben Gurion International Airport, Israel’s biological and chemical research center in Ness Ziona, and various command and control bases.
Among the missiles, the Khorramshahr-4, Iran’s heaviest intermediate-range ballistic missile, was deployed. Cooper highlights that this demonstrates not only tactical retaliation but also a strategic message regarding Iran’s missile capabilities.
Early reports suggest that the missile strikes may have been coordinated with UAV attacks, although full details remain unclear.
The picture below shows a perspective toward the Fordow nuclear enrichment site, captured by an Iranian journalist.
GBU-57 Massive Ordnance Penetrator (MOP)
The GBU-57B MOP is a precision-guided, conventional bomb designed specifically to destroy deeply buried and fortified targets.
Weight and Size: Each bomb weighs approximately 30,000 pounds (13,607 kg).
Purpose: It is intended for hard targets, such as nuclear enrichment facilities or underground command centers, where standard bombs would fail.
Penetration Capability: Depending on the composition of the soil or rock, the GBU-57B can penetrate up to 60 meters underground before detonation. This allows it to reach critical internal structures while minimizing surface damage.
Development History: Initiated by the US Air Force and supported by the Defense Threat Reduction Agency (DTRA), the MOP underwent extensive testing from 2004 to 2010. It succeeded the BLU-109, representing a significant technological advancement in bunker-busting munitions.
Operational Use: Tom Cooper explains that these weapons are carefully aimed to maximize strategic impact. The Fordow facility, for example, is estimated to be extremely deep, so strikes likely targeted entry points or operational areas rather than the facility’s full core.
Strategic analysis by Tom Cooper
According to Tom Cooper, the strikes demonstrate several strategic points:
Stealth and Reach: The B-2 Spirit’s stealth capabilities allow it to penetrate heavily defended airspace and deliver large, precise ordnance.
Facility-Specific Impact: While Fordow’s extreme depth limits observable destruction, targeting entrances and critical operational points can still disrupt nuclear activities. Natanz, with shallower depth, was more likely to experience structural damage. Esfahan’s surface facilities experienced limited physical damage but served a strategic disruption role.
Geopolitical Significance: The operation sends a clear message about the US’s willingness to act on perceived nuclear threats. Cooper emphasizes that these actions test both military capability and deterrence signaling.
Iranian Response: The missile strikes on Israel illustrate the risk of escalation, highlighting the delicate balance of regional power.
Resources and further readings: Sarcastosaurus and Helion & Company website
Photo by U.S. Air Force
