[kylania]

From http://uboat.net/history/aircraft_losses.htm

125 aircraft shot down by 97 individual U-boats for the loss of 31 U-boats either sunk during the attack or due to being located by other forces shortly afterwards and sunk. One source says that RAF Coastal Command (U-boat hunters) lost 700 aircraft (badly damaged, shot down and paid off - not all to U-boats of course) and sank 220 U-boats during the war. I've been unable to verify the RAF losses but the U-boat figure is about right it seems. These figures show the immense effort put out by the British to hunt down the U-boats and almost all the aircraft successes took place in 1942 and later.