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The scientific Idea that lies behind the aeroplane

The inventor of the first aeroplane, the heart-broken man who never knew of his success, was Samuel Pierpont Langley, a brilliant American scientist, born in 1834 at Roxbury, in Massachusetts. He, first of all inventors, tried to get a heavier-than-air machine flying independently. His plan was in opposition to the mighty authority of Sir Isaac Newton. Many trials showed him that an engine will carry a larger weight at 20 miles an hour than at ten miles an hour, and a still larger weight at 40 miles than at 20.

In plain language, the faster you move from place to place in the air the better will be your support from the body of atmosphere beneath the machine; the longer you remain in one place the greater is the likelihood of your toppling down; or, in other words, if you travel quickly you can carry greater loads with safety than if you travel slowly and risk a failure of support from the air beneath.

Numberless were the tests and experiments tried by Professor Langley before at last, on May 6, 1896, he went out with his friend Dr. Graham Bell, the telephone inventor, and launched a model from the top of a house-boat moored on the River Potomac. The first power- driven aeroplane weighed only 25 pounds. It had a wing-span of 13 feet, it was driven by a little steam-engine, and it flew ! It rose from the house-boat, glided smoothly into the air, sailed above the trees until the steam failed and the propeller ceased to work. Then it planed down into the river; was recovered, dried, and set flying again.