BALLOON JUMPING

Evening Post, Volume CXIII, Issue 100, 30 April 1927, Page 17

BALLOON JUMPING

PROSPECTS OF SPORT

UNCERTAIN AND COSTLY

(From Out Own- Correspondent.)

LONDON, 23rd March.

Balloon jumping as a sport appears to have its limitations. The ' recent experiment at Hendon, quite apart, from its tragic result—the experimenter was electrocuted on a live electric wire—was disappointing to some who had been hoping to see the inauguration of a new, amusing, and exhilarating sport. It was evident ■ that weather would play. an. important part, and that any wind of greater strength than a moderate breeze wpuld interfere. Obviously, too, it needs a fairly clear stretch of country, without many telegraph wires, railway lines, growing crops, or extensive woods in the way. lhe idea has come from America. The jumper is attached to a balloon, which has enough pull to raise him when he aids by springing off the ground. An accomplished jumper is said to be able -to cover a hundred yards and rise fifty or sixty feet each leap. The spectacle (ac- ;! °raing to the air correspondent of the Observer") was amusing enough, and no

doubt on a perfect day, witli the slightest breeze, it might provide a new "turn" at an aviation meeting. Timing the "jump" ia said to call for skill and judgment, lor apparently the idea is' to jump at the precise moment when the rigging becomes taut with the gaß:bag's ascent; in other words, to take advantage of the upward impetus. In a fitful wind, with the gasbag swaying wildly about, this is difficult; and, indeed, it is doubtful whether it makes very much difference. ■' ■ On this occasion the wind was Rtrong enough to make the jumps''long ones, and to keep them rather low; and it seemed, too, that they were to <{nite a considerable extent due to "kiting," the wind catching the balloon at the end of tho trail rope and lifting it as it would a hoy's kite. , ' The equilibrium of the balloon is a most delicate matter,'.and this delicacy is complicated by the inertia of its movements and by the very great air rcsi.stance of the huge bag. Except on an ideal day, under cloud, and with nn even and rather low temperature, there arc rapid variations of temperature, and, what is oijiiaily disturbing, constant processes of evaporation or of saturation. A passing cloud makes a great difference. The buoyancy of the balloon varies by many pounds in a few minutes. But the balloon jumper at the best has Bearcely nny margin of lift or of ballast. He must bo an expert balloonist and know when to valve, lor it would bo easy to rise (not by "jumping") to 200 feet or more, and it woulq bo dangerous to let the balloon attain its altitude limit lacking ballast to moderate the speed of descent. But in any case the sport would be iliflicult to pursue. It would be necessary to use hydrogen gas, which is very expensive. If coal gas were used a balloon of twice the capacity would be required, for coal gns lifts only half as much as hydrogen volume for volume. Coal gas would either mcun starting from the gasworks or transport of the gas in bags. . A staff of assistants would be necessary, and at the end of each run the balloon would have to be hauled back against the wind. There is no choice of direction and but little control of distance, 85, Fleet' street. ■'.-.-