This photograph appears in Mud, Blood, and Poppycock by Gordon Corrigan. He describes it as "a German flamethrower detachment taking on a tank," but conceded that it is a training exercise since the tank is an A7V.
On a website it is described as "German troops mopping up after a tank attack."
I find both explanations unlikely. I can't see a flamethrower being used on a perfectly good tank just for training, nor would a cameraman be in a position to take pics of a real mopping-up so close to the fighting. Anyone know the story of the pic? It seems more likely to be a flame-thrower detachment practising mopping up after an attack.
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
The effect of a flamethrower on a tank had been tested at Doncourt training ground by Major Reddemann. The flames would suck the air out of the tank and oil and petrol on the tank would start to burn. Use of flamethrowers against tanks was, however, restricted to favourable conditions, such as urban terrain. - You can see that in the picture, the flamethrower crew is practically committing suicide as a second tank follows the first. The picture is from a "tank demonstration" at a training ground (Saarburg in this case), where various methods to fight tanks were demonstrated.