What is bunker buster bomb that Israel needs from US to destroy Iran’s nuclear sites?

The Israel-Iran conflict is now in its fifth day.

On Tuesday, Tehran launched strikes across central Israel.

This came in the backdrop of Israel continuing to target sites in Iran including its military infrastructure.

But even this isn’t enough for Tel Aviv.

Israel now wants to use the GBU-57A/B Massive Ordnance Penetrator (MOP) bunker buster bomb against Iran’s nuclear sites.

But what do we know about the American-made bomb? How effective is it?

Let’s take a closer look

Origins

The GBU-57A/B Massive Ordnance Penetrator is designed by Boeing and manufactured by the US Air Force.

It is said to be the most powerful non-nuclear bomb in the US Air Force’s possession.

Guided by GPS, it is designed to hit enemy bunkers deep beneath the earth.

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Work on designing the bomb began in the early 2000s – a joint venture of Northrop Grumman and Lockheed Martin.

However, the project was abandoned after financial and technical difficulties.

Interest in the project picked up again after the US invasion of Iraq in 2003.

This is after the us military discovered that that their bunker busting bombs were not performing up to par.

The project kicked off again under the Defense Threat Reduction Agency (DTRA).

Initial testing began in 2004 after the DTRA joined hands with the Air Force Research Laboratory.

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The GBU/57B’s first static detonation tests were done in 2007.

The bomb was tested at the White Sands Missile Range in New Mexico.

In the meantime, Boeing had won the contract to integrate the bomb into aircrafts.

From 2008 to 2010, the bomb was repeatedly dropped from B-52 and B-2 bombers.

In 2011, the project was handed over to the US Air Force.

Technical Specifications

The GBU-57A/B Massive Ordnance Penetrator weighs around 14,000 kilos – around two African elephants combined.

It is around 20.5 feet long and has a diameter of 31.5 inches.

Its warhead, a blend of AFX-757 and PBXN-114 explosives, weighs around 2,500 kilos.

It is made of a special high-performance steel alloy.

Estimates about the bomb’s penetration capabilities vary.

Some reports say that the MOP can reportedly pierce 200 feet of concrete.

Others say it can penetrate around 60 meters of reinforced concrete with a strength of 5,000 PSIm as well as 40 meters of relatively hard rock and eight meters of reinforced concrete with a strength of 10,000 PSI.

The MOP comes with a delayed-action smart fuse.

This means the warhead does not detonate on impact, but rather does so only when it reaches a halt underground.

The US is said to be working on a new smart fuse for the bomb, though details remain scarce.

It uses the Global Positioning System/Inertial Navigation System (GPS/INS) system to find and lock on to its targets.

It is said to be accurate to within a few meters

The MOP can be launched only by the B-2 bombers.

According to experts, this is because of the bomb’s weight – It is considered too heavy to carry by the other aircraft.

This is a problem because the US Air Force has just 19 B-2 bombers currently in service.

The B-2 can carry two MOPs at once.

The MOP itself has five variants including the GBU-57F/B, which is the latest version of the bomb.

Details about the variants remain scarce and hard to confirm.

Stockpile and efficacy

The US is said to have a relatively small stockpile of these bombs.

Till, 2015 Boeing had delivered just 20 of these bombs.

However, there are reports that the us authorities are trying to scale up the MOP’s production.

The bomb and its continued development is important to America because the US’ adversaries including Russia, China, and Iran continue to build new facilities deep underground.

However, it seems that America’s enemies are already one step ahead of it.

A report in 2023 noted that Iran’s Natanz nuclear facility – which suffered damage only to its over ground enrichment building and none to its underground commercial Fuel Enrichment Plant (FEP) – may already be out of reach of the MOP after Iran made new additions to it.

Even if Israel can get its hands on the MOP, it remains to be seen if it can hurt Iran with it.

With inputs from agencies