Can tanks be killed with lasers? Australia wants to find out

This is an ambitious project, as current high-energy laser weapons only have enough punch to knock out relatively fragile drones and other non-armored aerial targets like mortars or missiles. A tank, especially a frontline main battle tank, is a different beast. Designed to withstand high-velocity large chunks of metal, tanks often have several inches or more of armor plating over most of their hulls and turrets. That's before you even talk about advanced armor like explosive reactive or composite armor.

If a laser were to be developed to penetrate that much metal, it would need to be monstrously powerful. But, as Popular Science points out, lasers also need a suite of other gear like cameras and tracking systems to keep a focussed beam of light on target long enough to do the desired damage. They are also incredibly power thirsty. However, Australia is confident it can be done.

“A future program to develop a directed energy weapon system able to be integrated onto [Australian Defence Forces] protected and armored vehicles, capable of defeating armored vehicles up to and including main battle tanks. The eventual deployment of directed energy weapons may also improve land force resilience by reducing the force’s dependence on ammunition stocks and supply lines,” explains the country's future defense strategy.

When using lasers to defeat tank armor, the key is to aim the beam of light at the tank and ensure that the beam is intense and enduring enough to achieve the objective. “One problem [laser weapons face] is the power needed to destroy useful targets such as missiles. To destroy something of this size requires lasers with hundreds of kilowatts or even megawatts of power. And these devices are only around 20% efficient, so we would require five times as much power to run the device itself,” wrote Sean O’Byrne, an engineering professor at UNSW Canberra and UNSW Sydney, in a piece explaining the promise and peril of anti-tank lasers.

“We are well into megawatt territory here — the kind of power consumed by a small town. For this reason, even portable directed energy devices are very large. (It’s only recently that the US has been able to make a relatively small 50kW laser compact enough to fit on an armored vehicle, although devices operating at powers up to 300kW have been developed),” he added.

As we said, an ambitious project indeed.