USAF orders 30K lb. GBU-57 bunker busters to prepare for Iran

Bunker Buster GBU-57

The US Air Force just dropped a massive reality check on anyone who thought we could casually bomb Iran's nuclear sites and then call it a day without restocking the pantry.

After unleashing 14 GBU-57 Massive Ordnance Penetrators during Operation Midnight Hammer back in June, the B-2 fleet needs more of these 30,000-pound bahdahbing bombs to keep the arsenal ready for whatever comes next. And yes, Boeing is getting the sole-source contract because surprise, they're the only ones who build this thing.

The partially redacted justification notice posted online last week lays it out plain: "this procurement and sustainment activity is critically needed to replenish the inventory of GBU-57’s, ended during Operation Midnight Hammer (21 June 25)."

Boeing has "uniquely acquired expertise over a period of 18 years of adapting this specialized weapon to meet evolving mission needs as MOP transitioned from proof-of-concept to Full Operational Capability," the document explains. Handing the job to anyone else? "Unacceptable delays." And the brass isn't mincing words on why speed matters: "No delay in award is acceptable for this effort. Delaying this requirement would undermine force readiness and efficient acquisitions for this key weapons program. A delay undermines Combatant Commanders’ capabilities, jeopardizes force readiness and strategic deterrence, hinders nuclear proliferation prevention efforts, and could result in loss of life."

The exact number of bombs being bought, the price tag, and delivery timeline? All classified or just not released. Because why spoil the mystery?

What is the MOP, anyway? Developed in the early 2000s by Boeing and the Defense Threat Reduction Agency, the GBU-57 Massive Ordnance Penetrator exists for one job: smashing through Hard and Deeply Buried Targets like underground labs, command centers, and those pesky nuclear facilities.

An Air Force fact sheet calls it "a weapon system designed to accomplish a difficult, complicated mission of reaching and destroying our adversaries’ weapons of mass destruction located in well-protected facilities."

This beast weighs 30,000 pounds (13,600 kilograms), with the warhead alone tipping the scales at 5,740 pounds (2,600 kg) and stretching over 20 feet (6 meters) long. It can punch through up to 200 feet (60 m.) of earth or 60 feet (18 m.) of reinforced concrete, making it the heaviest non-nuclear bomb we've got.

Scientific American once compared the kinetic impact to "800 to 900 megajoules (about 758,000 to 853,000 British thermal units) of kinetic energy – comparable to a 285-ton (285,000 kg.) Boeing 747-400 touching down at 170 mph (274 kph) or a 565-ton (565,000 kg.) Amtrak Acela train moving at 120 mph (193 kph)." In other words, it's a flying freight train with bad intentions.B-2 bomber drops a GBU-57 during a test

Operation Midnight Hammer marked the MOP's combat debut in June 2025, when seven B-2 Spirits hammered sites at Fordow, Natanz, and Isfahan with those 14 bombs. US officials called it a win, but independent looks suggest the results were mixed: Fordow took a serious hit, while Natanz and Isfahan might bounce back quicker than hoped.

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The strikes exposed both the MOP's raw power and its real-world limits, from the sheer size limiting which planes can carry it, to the headaches of ultra-hardened targets, and Iran's ongoing efforts to build better defenses. Replenishing the stockpile now isn't just housekeeping. It's a reminder that deterrence doesn't come cheap, and the mullahs aren't going to stop digging just because we hit them once.

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