 During the Battles of France and Britain, the German fighters had fuel injected engines and therefore did not suffer from this problem as the injection pumps kept the fuel at a constant pressure.The German pilots could exploit this by pitching steeply forward while opening the throttle, a manoeuvre that the pursuing British would be unable to emulate.The British countermeasure, a half roll so the aircraft would only be subjected to positive G as it followed German aircraft into a dive, could take enough time to let the enemy escape.