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Northrop Grumman ( NOC ) tests 50mm-plus cannon bullets

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Ukraine's military wants longer-range bullets to shoot

down

drones

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Using bullets against drones is much cheaper than using

missiles

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Fragmenting ammunition boosts anti-drone cannon

effectiveness

By Karol Badohal

WARSAW, Oct 3 (Reuters) - U.S. defence firm Northrop

Grumman ( NOC ) is testing higher calibre cannon bullets to

shoot down drones at lower cost, based on feedback from

Ukrainian soldiers who are increasingly facing swarms of

high-flying unmanned aircraft, a top company executive told

Reuters.

Governments are keen for ways to defeat low-cost drones with

equally low cost or cheaper interceptors. Currently the most

cost-effective way is to shoot down a drone with a bullet, which

costs pennies or dollars while many interceptor missiles, such

as the Patriot, cost millions of dollars each.

Northrop Grumman ( NOC ) has supplied Ukraine with its counter

unmanned aircraft system, M-ACE, that uses a medium-calibre

cannon to shoot down drones.

"They love the (anti-drone) system. They want more range

because they want to shoot these things down further out, which

completely makes sense... So we're taking that feedback,"

Northrop Grumman ( NOC ) Vice President Steve O'Bryan told Reuters on

the sidelines of the Warsaw Security Forum this week.

Ukraine has been adapting its air defences since Russia's

invasion in 2022 to be more effective against increasingly large

air raids, which can now comprise hundreds of drones at a time.

Northrop Grumman's ( NOC ) Bushmaster cannon currently uses 25-40

millimetre rounds and could shoot down drones up to a three-mile

distance, but increasing the calibre to 50 mm would

significantly broaden the range, even five-fold, O'Bryan said.

"They've (Ukrainians) asked: Hey, we need a higher calibre

so it goes further. And that's what we're working on right now.

We're in test on that," he said, adding the company was looking

into 50 millimetre and higher calibres.

He said the Bushmaster cannon, a chain-driven gun which

shoots multiple rounds per second, could hit in rapid succession

numerous targets attacking in swarms and would be much less

expensive than using often scarce air defence missiles.

"Not every target is a Patriot target, right? There's two

things with that. One is Patriot missiles are expensive... Even

if they weren't expensive, they're a low-density weapon. There's

just not that many of them," O'Bryan said.

"You need to save them for the targets that demand the

Patriot missile."

Cost-effect considerations led the company to equip the

Bushmaster with proximity ammunition that bursts into fragments

upon nearing its target, destroying it without the need for a

direct hit.

"We've got to get on the right side of that cost exchange

ratio curve, where we shoot a cheaper round than the drone,"

O'Bryan said. "And I think this is one of those solutions that

can do it. So, even if you have to fire multiple rounds, you're

still going to be on the positive side of that."