<p>American bomber forces made 150 attacks on targets, penetrating into German territory routinely about 50 miles (80 km) , and on one occasion as deep as 160 miles (72 km). They dropped 138 tons of bombs. Most of the bombing was done by one squadron during the day, normally equipped with 12 aircraft and probably with nine or 10 in commission. At a probably high bomb load weight of 500 lb (227 kg) per sortie, that works out to a total of 552 sorties into German territory.
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<p>Because of the short time the US forces were in combat, these figures only hint at the developing potential. Growth curves for almost any activity were swooping upward after the summer of 1918, and historians are fond of impressing the reader with what might have been, had the war lasted well into 1919.
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<p>From a starting point of essentially zero in April 1917, the United States had sent to France 6,861 officers and 51,229 enlisted men in aviation service only. Another 1,000 officers and nearly 20,000 men were still in training. American pilots at the front numbered 1,402 and there were 769 observers. Some were waiting specific assignments; the squadron totals were 767 pilots, 481 observers and 23 gunners assigned.
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<p>The impressive growth rate of the US Air Service is reflected in total personnel strengths in all ranks. In 1916, the Aviation Section, Signal Corps, comprised 311 officers and men. By 1917, that figure had risen four-fold to 1,218. During 1918, it jumped to 195,023 officers and men, a 627-fold increase. There has not been an expansion like that since, at least not in the United States air forces. No wonder there were problems.
