STRANGE COLLAPSE

New Zealand Herald, Volume LXXII, Issue 22161, 15 July 1935, Page 9

STRANGE COLLAPSE

STRATOSPHERE BALLOON UNEXPLAINED CAUSE ASCENT PREVENTED By Telegraph—Press Association—Copyright NEW YORK. July 12 A message from Rapid City, South Dakota, states the stratosphere balloon jointly owned by the National Geographic Society and the United States Army Air Corps collapsed through an unexplained cause an hour before it was scheduled to take off at 4 a.m. to-day. No one was injured. The top of the balloon burst open without warning and 375,000 cubic feet of helium escaped. The balloon is said to be the world's largest.

The balloon referred to in the cablegram, the Explorer 11., basically is a reproduction of the first Explorer, which gained an altitude last year within several hundred feet of the world's official record, but its equipment embodies many marked improvements. As an additional assurance of safety, the advisory committee of scientists for the proposed flight decided to inflate the balloon with helium. Tho balloons for tho 11 flights that have already penetrated the stratosphere have all been inflated with hydrogen. The advantage of using helium is that under no circumstances can the gas explode. Hydrogen becomes highly explosive in certain mixtures with air and must bo handled with extreme care.

A hydrogen-air explosion constituted the final stago in the destruction of the balloon Explorer I. Volume for volume helium will lift about 92 per cent of the weight lifted by hydrogen. To enable the 1935 balloon, filled with helium, to rise as high as the 1934 balloon, filled with hydrogen, was capable of reaching, the now bag was mado about 23 per cent greater in capacity. Although the 3,000.000 cubic footbbarl r loon of 1934 was the largest in the history of ballooning, the volume, of the new bag, fully inflated, is 3,700,000 cubic feet.

Increases were made in the weight of the material of the new balloon, but a recent estimate was that it would he able to reach the same theoretical maximum height as the Explorer L The estimate was that the new balloon could rise above sea level to an altitude of more than 70,000 feet, or between 13 and 14 miles, the existing official record, held by Lieutenant-Commander T. G. W. Settle and Major Chester Fordnev, being between 11 and 12 miles. The Explorer I. came within 624 feet of that record. Tho latest expedition was placed in the command of Captain A. W. Stevens, with Captain 0. A. Anderson as pilot and Captain R. P. Williams as alternate pilot. Following upon the experience of the previous year, notable improvements were made in the instruments of the new balloon and their disposition. It was proposed to carry six different instruments to record phenomena in connection with cosmic rays, and a large sunlight spectrograph instrument. Other pieces of equipment were to include air-sampling chambers, sun-brightness, sky-brightness and earth-brightness meters, and an instrument to record bursts of energy produced by the collision of cosmic rays with atoms of lead. The electrical conductivity of the air at various altitudes was also to be investigated.