The US Army is woefully short of front-line air defences. That was evident before Russia widened its war on Ukraine in February 2022. It’s even more evident 31 months into that wider war.
Drones are everywhere all the time all along the 700-mile front line in Ukraine and western Russia. If the Americans fought a war on the scale of the Russia-Ukraine war, they might struggle to defeat the thousands of drones that surely would buzz over the line of contact every day.
That’s why an effort to give the Army’s hundreds of mobile howitzers an air defence capability is so promising. And so urgent.
Back in July, the Army Rapid Capabilities and Critical Technologies Office in Virginia asked the weapons industry to submit information on possible hypersonic shells with air defence applications. Army officials want a company to deliver prototypes of super-fast, maneuverable shells no later than the fall of 2027.
The idea is to equip the Army’s existing fleet of around 700 M-109 Paladin tracked howitzers with ammunition that works against targets in the air: manned aircraft, drones, cruise missiles and rockets. A hypervelocity shell might travel as fast as nine times the speed of sound – anything above Mach 5 is usually deemed to be in the hypersonic realm – and strike with pinpoint accuracy.
With surface-to-air ammo, the M-109s could complement the Army’s dedicated short-range air defence vehicles: 300 ageing Avenger missile launchers fitted to Humvee trucks as well as future fleets of 170 wheeled air defence vehicles based on the newer Stryker infantry-carrier and 250 surface-to-air launchers mounted on heavy trucks.
If the howitzers could shoot down aerial targets, they would roughly double the Army’s battlefield air defence arsenal.
The need is clear. The Army hadn’t anticipated that, years into the Russia-Ukraine war, both sides would weaponize tiny, inexpensive drones – and launch them at each other at a rate of tens of thousands per month. The US service ended the Cold War with a large air defence force, but steadily cut back that force to save money.
The nadir arguably came during the heights of the US-led counterinsurgencies in Iraq and Afghanistan more than a decade ago, when air defence troops were relegated to escorting supply convoys in their old Avenger trucks, aiming the Avengers’ .50-calibre machine guns toward the ground to deter insurgent attacks.
By contrast, the stubborn Russian army never divested its Cold War air defences the way the US Army did. It went to war in Ukraine in 2022 with a thousand short-range air defence vehicles – three times as many as the US Army had at the time. But even with this larger air defence force, the Russian army is still overwhelmed by Ukrainian drones.
The air defence environment has changed, and the US Army now finds itself nearly defenceless against one of the most serious wartime threats. The land service is on its own: it should go without saying that the US Air Force isn’t going to send a $100-million stealth fighter to shoot down a drone costing at most a few tens of thousands of dollars.
Army leaders are beginning to internalise the scale of their air defence problem. In September 2020, Army testers organized a critical test of a howitzer-based surface-to-air system at the White Sands test range in New Mexico. An M-109 howitzer fired a BAE Systems-made 155mm hypervelocity shell at an incoming BQM-167 target drone, blasting it to pieces.
“Tanks shooting down cruise missiles is awesome – video-game, sci-fi awesome,” said Will Roper, then the US Air Force’s top scientist. (An M-109 isn’t actually a tank, but it does look like one.)
The problem is that the experimental BAE Systems 155mm round cost nearly $90,000. In asking industry for a scalable hypervelocity shell with air defence applications, the Army clearly aims to drive down the per-unit cost – and make howitzer-fired munitions practical for battlefield air defence.
It’s a great idea. If there’s a downside, it’s that it might take too long to convert into an actual front-line capability. The Army is content to wait until 2028 to deliver drone-killing howitzer shells to combat batteries. But the service could find itself fighting a Ukraine-style drone war well before then.