Cover from Blackhawk #252 by Dave Cockrum
Via: the dcuguide
"The weapon known as the War Wheel was invented by a professor Merson, who had willingly defected to the Nazis. Arriving on the scene in 1940, the gigantic wheel, spiked and heavily armored so that no artillery shell could penetrate it, was opposed by the flying squadron known as the Blackhawks. After a long and hopeless fight, the Blackhawks learned that the War Wheel could only be defeated if one could find a way to eliminate the men steering it. Blackhawk attacked it with high voltage wires, the electric shock of which killed the men within the machine, and the Wheel crashed to the earth.
The War Wheel was recreated time and again, only to be defeated by the Blackhawks or the Suicide Squad. The last incarnation of the machine was destroyed by Rick Flagg, Sr., who sacrificed his own life in the mission.
One War Wheel later turned up as an exhibit in the Victory Museum on Blackhawk Island."