HOW FAST CAN WE GO?

Waipa Post, Volume XXIV, Issue 1666, 24 September 1925, Page 6

HOW FAST CAN WE GO?

SPEED TESTS AND THEORIES.

A MASTERY OF THE AIR IS IN SIGHT.

First the .human runner, then the horse, then mechanical devices—cycle, auto, airplane. "Have we reached the limit?" asks Jean Cabarets, writing in Le Quotidien (Paris). No, we can in theory quadruple our present record speed in the air, and we can greatly excel it even in practice. Not, to be sure, under present conditions, hut when we have still lighter and more powerful engines and learn to fly so high that air resistance ceases to trouble us. Modern runners, though they still break .records, do so with increasing difficulty. For instance, take the Olympic 800 metre ■dash. In 1896 this was done in 2min. Usee. In 1904 the time was lowered to lmin. 59sec, in 1920 to Imin. 53 2-5 sec, in 1924 to lmin. 52 2-ssee. And the world's record has remained since 1912 at lmin. 51 9-10 sec. This shows that for 30 years past—those of a real renaissance of sports—runners have made only small gains.

'The same has been true with horses. The record of a running horse is about 45 kilometres (28 miles) an hour. In the 17th century, when the improvement of the breed bad not been begun, the Duke of St. Simon rode from the Louvre to Versailles and back —50 kilometres —in less than an hour, on a bet. Human or animal, the muscle has not made much progress' in the conquest of speed. Applied to a machine, such as a bicycle, muscular effort has given more tangible results, which the steady improvement of the device has increased. The record of the auto is 251 kilometres an hour, to reach which it had to exert 200 horse power. -Vehicles may be equipped with motors of 500 to 1000 horse power. But will such an engine retain the characteristics of an automobile? Trains on a railway have exceeded 200 kilometres (124 miies) an hour in tests with electric motors. The fundamental obstacle —the air—is opposed to speeds of this order, at least in practice. And the flyer? He has attained since the war additional speeds of about 200 kilometres an hour. But the stages of this conquest are getting harder and harder Adjutant Bonnet promises to reach 500 in the near future by doing without his radiators and his landing gear. This is nothing but an avowal that such a tour de force cannot be carried much further into the of utility.

Nevertheless we.cannot give up our efforts to go quicker and quicker. We have the use of the gas turbine in sight. Extremely interesting laboratory experiments with it are now being made. We should study high altitudes where there is little air resistance to overcome. And then what will be the speeds? A thousand kilometres an hour? Yes, almost at the outset. But here also a theoretic limit appears. Whatever the motor, even in an absolute void, the flyer can never make a speed in excess of half the velocity of his exhaust gas. This is the principle of the rocket. Let us put this exhaust speed at 1200 metres a second. This will give to the ideal rocket-airplane a limiting speed of about 2000 kilometres (1240 miles) an hour. These figures, in truth, are somewhat illusory. The search for a top speed is not so deceptive!, however, as it seemed at first. The margin is still great, but not so much as to forbid us to hope that it will be readied in our own generation.