Four years ago in Melbourne, I had the privilege of listening to a talk by Tony Gaze DFC and Two Bars - an Australian pilot with 12 confirmed, who flew with Douglas Bader and Johnny Johnson. He was flying a Spitfire over Germany and spotted two German tanks at a cross-roads. One was a Tiger tank.
In his own words he said that there was no harm in having a go at the tanks as he knew that his 20mm shells would not penetrate the armour but that it might stir things up a bit. He thought in fact that the two tank commanders were having a cosy chat at the time.
He opened fire and to his surprise the Tiger blew up. He thinks that his shells may have entered the open crew hatch and hit the fuel tank or magazine.
When he returned to base he claimed one Tiger tank but his colleagues said bulls..it no way he could get a tank. Fortunately his claim was verified by his wing man who saw the whole show.