In WWII, British anti-aircraft gunners were so notorious for shooting at anything that flew that their commander, Air Marshall Pyle, wrote in his autobiography, "It is said that the British anti-aircraft gunner can only recognize three types of aircraft: approaching and considered hostile, receeding and considered friendly, and Lysanders."

In the book, "Operation Aphrodite", there is a story about an American B-24 bomber pilot who was so tired of being shot at by the British that he told his bombadier to save one bomb. When his plane came under fire, he dropped the bomb, saying "Truly it is better to give than to receive."

As bad as their land based gunners were, those on British ships were much worse. They'd shoot at anything that flew, approaching or receeding, even planes as distinctive as the P-38 Lightning.

Today, the British probably don't have as many friendly fire incidents as they did back in WWII. Of course, their military is only a few percent as large as it was back then, too.