There is also the issue of rockets. I understand that the American rockets mounted on P-47's were much more destructive than the rockets that the British mounted on their Typhoons.
From:
http://www.usaaf.net/ww2/dday/ddpg8.htm
"There is, however, an interesting report from Montgomery's 21st Army Group that questions the alleged success that British air-to-ground rockets enjoyed against tanks and motorized transport."
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In 1944, America introduced the The 140 lb. HVAR rocket, affectionately dubbed the "Holy Moses" because of its impressive destructive effect.
The below excerpt indicates that the American rocket could penetrate 75mm of armor or four feet of reinforced concrete at 1,000 ft.
From:
http://66.102.7.104/search?q=cache:...rmans"+++"surrendered"&hl=en&client=firefox-a
As deadly as the P-47 could be on the German war machine, it became even deadlier shortly after D-day when the first American rockets that could be fired from the wing of a fighter plane arrived. (The British had used rockets from their airplanes, but they were not powerful enough to take out a German tank).
"Our rockets were the first 'high velocity' in use," he said, "they could penetrate 4 feet of reinforced concrete (and 3-inch armor) at 1,000 feet."
The rockets were developed by Cal Tech scientists. Park said they were manufactured in the Los Angeles area. The plant was turning out 100 a day, delivered directly to the front lines on Army C-54 transport planes.
Fifteen airplanes in the 406th were initially equipped with the new U.S. rockets (half of the P-47s were eventually fitted with the weapons).
Once the pilots learned how to maneuver their planes into a proper position to accurately hit the target, they took off from England and flew to France a few weeks after the Normandy landing looking for tanks out in front of American troops to test out their new weapons. Park spotted his target, set his aircraft, and launched a rocket taking out a pair of tanks that were rumbling along in the countryside. With that shot, Park became the first pilot ever to take out an enemy tank with a rocket fired from the wing of an airplane.
The Rocket contained a Navy 5-inch shell in a 6-foot tube that was filled with rocket propellant. Firing the weapon was a little more difficult than dive bombing, according to the former P-47 pilot.