National Defense: Tank Test

Above the snapping signal flags in the swirling tank battles in Libya hovered the ghostly tradition of Allenby, Jeb Stuart and all the great cavalrymen back to Genghis Khan. But in the clanking, barking tanks rode the spirits of the hard-eyed, dusty men of the U.S. Armored Force. For most of the tanks carrying the British regimental crests out into battle were U.S.-made.

To Washington this week came more reports from official observers of the battle. These reports indicated that U.S. tanks were doing a cracking good job; but the returns were not all in. U.S. tankers and technical men waited for the rest of the story.

On the battlefield were around 400 light (13½-ton) U.S. tanks, each armed with a 37-mm. cannon and machine guns, some 50 U.S. mediums—30-tonners armed with a 75, a 37 and machine guns. Those were the equals, on paper, of the Germans’ heavy (32-ton) Mark V.

Whether the Chrysler-made U.S. mediums had yet seen action, Washington did not know. But American Car & Foundry Co.’s lights had seen plenty. Of both the lights and mediums, Washington knew one thing for certain. They had at least 50% more speed (light’s top, 45 m.p.h.; medium’s, 30) than anything of the same size in Europe. And more power: 250 h.p. for the lights, 400 for the mediums.

Observers had reported that the air-cooled aircraft engines in U.S. tanks were less vulnerable than the liquid-cooled European engines. And they needed no stops for the water that in Libya is as precious as gold.

Both observers and newsmen reported that the nimble lights could wheel and pirouette faster than the German tanks; that the thin side armor of German mediums was poor protection against the 37-mm. cannon of the U.S.-made tanks.

What tankers wanted to hear most about was the tank’s endurance qualities; and of that it was too soon to judge. In field tests, the U.S. tanks had shown they could stand two or three times as much wear as European machines. The engines gave at least 200 hours of hard running between layups for repairs. The rubber treads, characteristic of U.S. tanks, lasted between 2,000 and 2,500 miles in desert tests, against a maximum of 800 for the best track Europe produces. Some reporters wrote that the British thought all-metal treads were better than rubber. The Ordnance Department was ready to bet that the British would soon change their minds.

There were still other unanswered questions: Was U.S. riveted armor as good as the riveted armor of the Germans? Whether it was or not, better was on the way. Last week American Locomotive Co. ran off its first medium with a cast-steel upper hull. All its surfaces are curved (to make shots glance off). It is also lighter, faster to build.

Meanwhile, the U.S. will shortly field-test a 55-ton heavy, built by Baldwin Locomotive. Whether it will go into mass production is a question the Battle of Libya may well decide.