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GLSDB upgrades counter Russian jamming, enhancing

effectiveness

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Ukraine's ATACMS supply depleted, GLSDBs to fill gap

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GLSDBs developed by SAAB and Boeing ( BA ), tested for resilience

By Mike Stone

WASHINGTON, March 13 (Reuters) - The U.S. is poised to

resume shipments to Ukraine of long-range bombs known as

Ground-Launched Small Diameter Bombs (GLSDB), after they were

upgraded to better counter Russian jamming, two people familiar

with the weapon told Reuters.

The munitions will arrive amid reports that Ukraine's supply

of similarly-ranged Army Tactical Missile Systems (ATACMS) has

been depleted.

The glide-bombs were purchased under the U.S. administration

of former President Joe Biden using the Ukraine Security

Assistance Initiative. The U.S. has bought nearly $33.2 billion

worth of new arms and military equipment for Kyiv directly from

U.S. and allied defense contractors.

President Donald Trump's administration agreed on Tuesday to

resume military aid and intelligence sharing with Ukraine after

Kyiv said it was ready to support Washington's proposal for a

30-day ceasefire with Russia.

In recent weeks, 19 GLSDBs were test-fired to assess the

effectiveness of the upgrades. Part of the modifications

involved reinforcing connections within the weapon to enhance

its resilience, the people said.

The reintroduction of the GLSDB onto the battlefield could

occur in the coming days, as a stockpile is already present in

Europe. The last time Ukrainians used the weapons was months

ago, one of the people said.

Russian jamming had kept many of Ukraine's relatively new

long-range GLSDBs from hitting their intended targets, three

people familiar with the challenges told Reuters last May.

Ukraine over the last year sought weapons with longer ranges

than the 43 miles (69 km) of U.S.-provided GMLRS rockets so Kyiv

could attack and disrupt Russian supply lines and muster points.

To answer that call, Boeing ( BA ) offered a new weapon to

the Pentagon with a 100-mile (161-km) range, the GLSDB. The

glide-bomb has small wings that extend its reach, and it

comprises the GBU-39 Small Diameter Bomb (SDB) and the M26

rocket motor, both of which are common in U.S. inventories and

relatively inexpensive.

Boeing ( BA ) declined to comment.

But the GLSDB's navigation system, which enables it to be

steered around obstacles such as mountains and known anti-air

defenses, had been successfully targeted by Russian jamming, the

three people briefed on the matter said in May.

The bomb is made jointly by SAAB AB and Boeing ( BA ),

and was in development well before Russia's full-scale invasion

of Ukraine in 2022.

Jamming happens when huge amounts of energy are broadcast

into an area, overwhelming a device's signal. Russia has used

the tactic on Ukrainian radios, drones and even GPS-guidable

Excalibur 155-millimeter artillery munitions.