The inflatable, life-size dummy tank was moored to the ground during a training exercise near Tredegar, south Wales.
But 80 mile per hour winds tore the battle tank replica from ropes tethering it to the ground and the vehicle is officially "missing in action".
A widescale search including a helicopter is now underway for the errant inflatable.
On Monday a military spokesman said they were anxious to hear from anyone who may have woken during the morning to find a tank in their garden.
Up to 860 soldiers were taking part in the annual Cambrian Patrol exercise at Trefil at the foot of the Brecon Beacons.
The troops were enacting a battle scene using "enemy positions" created using the tank replica, which is Royal Air Force property.
The army is now scouring the hills of mid Wales using a helicopter to find the inflatable.
Reality exercises
Red-faced Sergeant Major Brian Pratt said: "If anyone's found my tank, please give us a bell.
"It looks like a proper tank - from 200 metres away, you would think it was a green tank with wheels and a barrel. It really looks the part.
"It is about the size of three cars. It would fill a big garden. When deflated, it takes three men to lift," the sergeant major told BBC Radio Wales.
"We have got about six blow-up tanks. We use them every year for different exercise to make the exercise as realistic as possible.
"It was particularly unusual weather."
The other inflatables used in the exercise were deflated and removed before the winds could carry them away.
Meanwhile, a 25 foot-high inflatable replica of fast food mascot Ronald McDonald is also still missing after it was whisked by high winds from a Newport restaurant last week.