U. S. Navy Blimp, First in World to Use Helium, Makes Successful Flight Here From Norfolk -- December 1, 2021

Washington Times, 16-December-1921

100 years ago today, on 01-December-1921, US Navy blimp C-7 made the first successful dirigible flight using helium as the lifting gas. The crew needed lots of coffee when they landed near Washington, DC. Commander Zachary Lansdowne died in 1925 in the crash of USS Shenandoah, ZR-1. The Assistant Secretary of the Navy was Theodore Roosevelt, Jr. Rear Admiral William A Moffett died in 1935 in the crash of USS Akron, ZRS-4. 

Naval Blimp C-7 Circles the City;

Successful Test of Helium Gas

Naval blimp C 7 pointed its nose out of the south shortly after 10 o'clock this morning, circled the city, and came to earth at the Anacostia naval air station to complete successfully the first flight ever attempted with helium gas in lieu of hydrogen.

The blimp, like a huge silver cigar, came proudly around into the wind and settled down with the ease of a veteran at 10:20 o'clock, completing the trip from Hampton roads in three hours and forty-three minutes, under adverse weather conditions. She braved a snow flurry on the last forty miles of her trip, which left the gasbag shimmering and shining when | she landed.

The crew, which included Lieut. Commander Zachary Lansdowne, commanding: Lieut. Commander R. F. Wood. Lieut. A. T. Sewell and Chief Machinist G. C. Ferris, were suffering slightly from the effects of the cold weather, hopping to the ground with benumbed hands and chattering teeth.

Commander Proud of the Ship.

"I'm proud of the ship." said her commander when she landed. "Helium is a great product. It may not have the lift that hydrogen gives, but it gave us no trouble whatever during this flight. We came up in nice time, but were never more than 300 feet high on account of the condition of the weather. It's a great product."

A number of officials of the Navy department visited the ship this morning. These included Rear Admiral Moffett and Assistant Secretary of the Navy Theodore Roosevelt. Both congratulated the commander and crew on the success of the flight.

Hot coffee awaited the crew, while batteries of photographers held them up for snapshots and motion pictures. A naval plane went up and circled the blimp to secure motion pictures of record for the completion of the flight.

The air ship departed again for Hampton roads at about 12 noon and was expected to arrive at the base before 3:30 o'clock.

The C-7 is the first lighter-than-air craft in the world to make a flight inflated with helium gas. Practically the world's entire supply of this gas was carried in the silver bag. The big advantage of the helium is that it is non-explosive, while hydrogen is high-explosive. Static or electric connections provide no liability for explosions in a helium bag, nor is there danger of ignition from sparks of motor exhausts. Probably the greatest disadvantage in the use of helium is its cost of production, its availability and its buoyancy compared to that of hydrogen. Hydrogen, with 100 per cent purity and under standard atmospheric conditions. has a buoyancy of 70 pounds per 1,000 cubic feet of air displaced, while helium under similar conditions has 64.4 pounds lift.

The Navy maintains a helium plant at Fort Worth, Tex., where helium is extracted from natural gas by compressor systems. It is required that a plant of this character be located where there is an abundance of gas and also an abundance of water for cooling the numerous compressors. The natural gas, after passing through this plant becomes a purer illuminating gas than before, when it is then returned to the gas company for commercial use. The natural gas is first passed through lime, which removes carbon dioxide; it is then liquefied, leaving nitrogen and helium gases, which are drawn off and further compressed. thereby liquefying the nitrogen and leaving the helium, which is drawn off and compressed into cylinders and placed in storage for shipment.

C Ships Especially Reliable.

The class C ships, under which C-7 comes, are twin engined, and especially reliable for patrol and convoy work. Their dimensions are: Length, 192 feet; maximum diameter of envelope, 41 feet 9 inches; maximum height, 60 feet; maximum width, 53 feet 7 inches. The envelope has a designed volume of 181,000 cubic feet. Their fixed weight ready to fly is 7,940 pounds, leaving the balance for disposable weights consisting of crew, gasoline, oil. navigating equipment, radio, food, drinking water, ballast, bombs, guns etc.