Helium vs. Hydrogen

A Plot. According to Dr. Harrison E. Howe, Editor of Industrial and Engineering Chemistry, a "plot" is under way to divert public interest from helium. Asserting that electrical sparks twelve to eighteen inches in length were seen on the helium-filled Shenandoah on the night of its great adventure (TIME, Jan. 28) and that these sparks would have set it on fire, had it been filled with hydrogen, Dr. Howe--through the pages of his journal--demanded to know why this important fact has been overlooked in official and press discussions. "What is back of this obvious effort to have the American people forget helium?"

Then--in a direct personal attack-- the famed chemist inquired: "Is it possible that the apparent aversion to helium is due to the influence of a German engineer occupying a responsible place in our air service? America possesses a helium monopoly. It is conceivable that our good fortune is regarded jealously by those who remain loyal to other countries under all circumstances."

Heinan Described. The German engineer in question is Captain Anton Heinan, who (employed by the U. S. Navy Department) was aboard the Shenandoah on the occasion of its accidental flight. Short, slenderly built, Heinan has a keen and piercing blue eye, an air of imperturbability. Bred in the great German port of Hamburg, he was a seaman before becoming Germany's most noted dirigible pilot. He flew the Bodensee between Berlin and Friedrichshafen in south Germany on passenger-carrying service with almost clocklike regularity, claims to have carried 100,000 passengers without a single casualty in ten years' piloting. In spite of his imperfect English, he was able a fortnight ago, tugging the while at his well-trimmed beard, to keep the attention of some 200 men-- aeronautical students at New York University, Army and Navy men, and aviation enthusiasts generally--riveted on a lecture of more than two hours' duration. He has taken out his first papers, intends to make the U. S. his home, foresees here tremendous possibilities in his chosen field.

Heinan's Reply. Heinan made a strong rejoinder to Editor Howe. The Shenandoah will be in commission in April. If Great Britain or any other Power threatens to forestall the U. S. in a voyage of discovery to the Polar areas this Summer, the German pilot is prepared to make an immediate dash to the Pole, not by way of Alaska-- where mooring masts and other equipment have to be carefully prepared-- but in a five-day non-stop flight of 6,000 miles from Lakehurst straight to the Pole and back. And this at 24 hours' notice. But it would be possible only with the lighter hydrogen gas. "With hydrogen, we could make the trip to the Pole and back easily and safely. With helium it is necessary to have mooring masts, where the ship can be tied up because she could not carry enough fuel for the round trip."

Hydrogen Arguments. While helium is exceedingly light as compared with air, it is somewhat heavier than hydrogen. The total lift of a helium-filled dirigible is accordingly some 10% less than that of the hydrogen-filled airship. The difference does not appear important at first sight, but the total lift of the gas carries the structure, the motors and the crew. It is only the last 20% or so that is available for carrying fuel, and hence a difference of 10% in the gross lift may spell a difference of 50% in the fuel-carrying capacity. On long-distance flights this difference is vital.

Nor is the danger of fire totally eliminated with the use of helium; the gas-tanks and the fuel system generally are still vulnerable. But when a ship is properly designed and carefully handled, the danger of fire is comparatively small, even with hydrogen.

Another strong argument of hydrogen partisans is the fact that owing to the minute quantities of helium found in the natural gas at its source, an extremely expensive system of fractional distillation is necessary and the cost will always remain excessive.

General View. For a number of years the Navy has held that our helium monopoly meant supremacy in the air as far as dirigibles were concerned. But recently the attitude of the Bureau of Aeronautics has changed and its officers in various public utterances have advocated a return to hydrogen.

A strong technical case could be worked up for either side.